MXPA98000986A - Chemical vapor deposit and dust formation using thermal spraying with supercritical or almost supercrit fluid solutions - Google Patents

Abstract

A method for depositing chemical vapor using a very fine atomization or vaporization of a reactor containing liquid or liquid-like fluid almost at its supercritical temperature, where the resulting atomized or vaporized solution is introduced into a flame or plasma torch, and a powder or a coating deposited on a substrate is formed. The combustion flame can be stable from 10 torr to multiple atmospheres, and provides the energy environment in which the reagent contained within the fluid can be reacted to form the desired powder or coating material on a substrate. The plasma support also produces the required energy environment, but, unlike the flame, an oxidant is not needed so that stable materials can be formed at only very low partial oxygen pressures. By using either the plasma torch or the combustion plasma, coatings and powders formed in the open atmosphere can be deposited without the need for a reaction chamber, but a chamber can be used for several reasons including the separation of the process from the environment and the regulation of pressure

Description

DEPOSIT OF CHEMICAL VAPOR AND FORMATION OF DUST USING THERMAL SPRAYING WITH SOLUTIONS OF SUPERCRITICAL OR ALMOST SUPERCRITICAL FLUID BACKGROUND OF THE INVENTION I. Field of the Invention This invention relates to methods of powder formation and deposition of thin film from reagents contained in liquid fluid or liquid-like solutions, whereby the fluid solution, close to its supercritical point temperature is released in a region of low pressure causing a very fine atomization or vaporization, superior to the solution. The gases entrain or feed in the dispersed solution and flow rapidly in a flame or plasma support. The reactants react in either: 1) dust that is collected; or 2) a coating from the vapor phase on a substrate placed in the resulting gases and vapors. The release of the fluid near its supercritical point temperature causes dispersion and expansion resulting in a very fine nebulization of the solution, which produces an improved quality of powder and film, improved deposition rates and increases the number of possible useful precursors.

P1082 / 98MX II. BACKGROUND OF THE INVENTION Chemical vapor processing has been used extensively for the production of powders and coatings. Chemical vapor deposition ("CVD") is a term used when forming coatings on a substrate. CVD production of coatings is widespread. Many of these coatings are only nanometer thick and smooth at least 5% of the coating thickness. The reaction and agglomeration of the steam material reacted in the gas stream forms powders which may be commercially useful. Actually, nanopowders are required in the formation of nanomaterials that have different properties from those of bulk materials. These properties of the materials can be adapted by controlling the size of the aggregates of the nanopowder. Similarly, coatings of less than 50 nm may have properties that are different from thicker films, and the properties change further as the coating is thinned. It is desirable to form these powders and coatings at low production and capitalization costs and with simple production processes. However, for many materials there is a very limited selection of available precursors that can be vaporized and used for CVD Traditional P1082 / 98MX Being able to form coatings in the open atmosphere openly facilitates the handling of the substrate and the flow through the coating process. In addition to thin films, thick coatings and quality bulk materials at low cost are also desirable. The chemical combustion vapor tank ("CCVD"), a recently invented CVD technique, allows the deposition of thin films in the open atmosphere. The CCVD process offers several advantages over other thin film technologies, including traditional CVD. The key advantage of CCVD is its ability to deposit films in the open atmosphere without any expensive furnace, vacuum or reaction chamber, as a result, the initial capitalization requirement of the system can be reduced by up to 90% compared to a system based on of emptiness. Instead of a specialized environment, which is required by other technologies, a combustion flame provides the necessary environment for the deposit of the elementary constituents of the solution, vapor or gas sources. The precursors dissolve in general in a solvent that also acts as the flammable fuel. The tanks can be made at atmospheric pressure and temperature inside a discharge hood, outdoors, P1082 / 9BMX or inside a chamber for the control of gases or surrounding pressure. Since the CCVD uses general solutions, a significant advantage of this technology allows quick and simple changes in the impurifiers and the stoichiometries that facilitate deposit of complex films. In contrast to conventional CVD, where the vapor pressure of the precursor is an interest dictating the expensive, high vapor pressure precursors, the CCVD technique generally uses soluble, inexpensive precursors. In addition, the precursor vapor pressures do not play a role in the CCVD because the dissolution process provides the energy for the creation of the necessary ionic constituents. In general, the precursor materials used for traditional CVD deposits are 10 to 1000 times more expensive than those that can be used in CCVD processing. By adjusting the concentrations and constituents of the solution, a wide range of stoichiometries can be deposited quickly and easily. Additionally, the CCVD process allows both the chemical composition and the physical structure of the deposited film to adapt to the requirements of the specific application. Unlike CVD, the CCVD procedure is not P1082 / 98MX confines to a low pressure, inflexible, expensive reaction chamber. Therefore, the reservoir flame, or a flame bank, can be moved through the substrate to easily coat large and / or complex surface areas. Because the CCVD process is not limited to specialized environments, the user can continuously feed materials into the coating area without interruption, thus allowing for batch processing. In addition, the user can feed the tank to specific areas of a substrate by simply controlling the drying time of the flame (s) in those areas. Finally, CCVD technology generally uses halogen-free chemical precursors that have a significantly reduced negative environmental impact compared to conventional CVD, resulting in more benign byproducts. Numerous materials have been deposited via CCVD technology with the combustion of a precursor solution, premixed as the sole source of heat. This inexpensive and flexible film deposition technique allows for wider use of thin film technology. The CCVD process has much the same flexibility as thermal spraying, it still creates conformation, quality films, similar to those associated with CVD. Traditional CVD often requires months P1082 / 98MX of effort for the successful deposit of a material. With CVD processing, a desired phase can be deposited in a few days and at a fraction of the cost of traditional CVD. By providing these coating capabilities cheaply, the CVD process can expand the commercial opportunity for thin films, including use in tribological applications, thermal protection, wear, space environment protection, optics, electronics, structural and chemical resistance. In this way, government and commercial users can benefit from the advantages of thin films over thick films, including their high adhesion to the substrate, controlled microstructure, greater flexibility, reduced consumption of the raw material and a reduced effect on the characteristics of operation and / or dimensions of the coated system. Ichinose, H. Shiwa Y., and Nagano, M. Synthesis of BaTi03 / LaNi03 and PbTi03 / LaNi03 Thin Films by Spray Burning Flame Technique, Jpn. J. Appl. Phys, Vol. 33, 1, 10 p. 5903-6 (1994) and Ichinose H., Shiwa, Y., and Nagano, M. Deposition of LaM03 (M = Ni, Co, Cr, Al) - Oriented Films by Spray Combustión Flame Technique, Jpn. J. Appl. Phys, vol. 33, 1, lOp. 5907-10 (1994) used the processing of P1082 / 98MX CCVD, which they called the spray combustion flame technique, by ultrasonically atomizing a solution containing a precursor, and then feeding the resulting nebulized solution, dispersed in an argon carrier gas in a propane combustion flame. However, these atomization techniques can not achieve the highly desirable submicron capabilities that are important for obtaining improved powder and coating formation. U.S. Patent No. 4,582,131 (the "patent '731") discloses a use of a supercritical fluid molecular spray for depositing films. However, the? 731 patent is for physical vapor deposition (PVD), which differs from the independently recognized field of CVD by not having chemical reagents and which is normally operated at high vacuum. additionally, the plasma or flare torch is not used in this method, and only supercritical fluid solutions are considered. Chemical reagents are beneficial because of their physical properties, including greater safety. The plasma and flare torch allow coatings in the open atmosphere according to the additional source of heat. The deposit material of the? 731, however, does not start from a reagent, and thus will not react to supercritical conditions.

P1082 / 98MX US Patent No. 4No. 970,093 (the "093 patent") describes the use of supercritical fluids and the CVD for depositing films. The work related to the patent 0 083 is described in B. M. Hybertson, B. N. Hansen, R. M. Barkley and R. E. Sievers, Supercritical Fluid Transport-Chemical Deposition of Films, Chem. Mater., 4, 1992, p. 749-752 and Hybertson et al. And B.N. Hansen, B. M. Hybertson, R. M. Barkely and R. E. Sievers, Deposition of Palladium Films by a Novel Supercritical Fluid Transport-Chemical Deposition Process produced, Mat. Res. Bull., 26, 1991, p. 1127-33. The 093 patent is for traditional CVD without a plasma or flame torch and does not consider techniques capable of open atmosphere such as CCVD, which has the associated advantages discussed above. Additionally, they are considered supercritical fluid solutions; liquid solutions are not treated near the supercritical point. All of the precursor of the 093 patent is carried in the supercritical solution which can limit the useful precursors due to the reactivity and solubility of the supercritical edges. B. Merkle, R. N. Kniseley, F. A. Smith and I. E. Anderson, Superconducting YBaCuO Particulate produced by Total Consumption Burner Process produced, Mat. Sci. Eng., A124, p. 31-38 (1990), J. McHale et al., P1082 / 98MX Preparation of Hihg-Tc Oxide Films via Flaming solvent Spray, J. Supercond. 5 (6), p. 511 (1992), and M. Koguchi et al., Preparation of Yba2Cu3Ox, Thin Film by Flame Pyrolysis, Jpn. J. Appl. Phys 29 (1), p.L33 (1990) describe the use of a flame to deposit films of what was called a "spray pyrolysis" technique. Both Merkley et al. And McHale et al. Deposited Yba2Cu3Ox from a sprayed solution, burned on substrates, but the deposit conditions resulted in low quality thyrolysis and particle-type coatings. Koguchi et al. Atomized a 0.03 mol / l aqueous solution and transported the resulting mist in a flame of H2-02 and deposited a coating of a thickness of 10 μm in 10 minutes on a substrate of zirconium stabilized with yttria (YSZ) heated by the flames with much of the pulverized material that is lost in transportation due to the method used. The temperature, measured in the upper part of the substrate, reached a maximum of 940 ° C. However, the flame side of the substrate is generally expected to be 100 ° C to 300 ° C higher in temperature than the upper part that would be in the melting range of Yba2Cu3Ox. The resulting film from Koguchi et al. Had a preferred orientation on the C axis, strong and, after annealing with oxygen to P1082 / 98MX 850 ° C for eight s, the film showed zero resistivity at 90 ° K. Koguchi and collaborators named their method "flame pyrolysis", and were probably depositing at temperatures near the melting point of Yba2Cu3Ox. The concentrations of the solution and the deposition rates are greater than those useful in the processing of CCVD. Therefore, there is a need for a coating method that achieves excellent results below the melting point of the coating materials. The present invention satisfies this need because the fine atomization of the near-supercritical fluid improves the quality of the film by allowing the formation of films deposited by steam at lower deposition temperatures. McHale and collaborators successfully produced films of a thickness of 75 to 100 μm of Yba2Cu3O? and Bi..7Pbo.3Ca2Sr2Cu3O? or when burning a pulverized solution of nitrates dissolved in liquid ammonia in a gas stream of N20, and by burning nitrates dissolved in either ethanol or ethylene glycol in an oxygen gas stream. The results suggest that the films are in the form of particles and not in pure phase. The coatings of Yba2Cu3Ox have to be tempered at 940 ° C for 24 s and the coatings of Bi?.? Pb0.3Ca2Sr2Cu3O? 0 treated with heat at 800 ° C for 10 s and then at 860 ° C for 10 s.

P1082 / 98MX s to produce the desired material. Even after oxygen quenching, zero resistivity could never be obtained at temperatures above 76 ° K. The concentrations of the solution used were not reported, but the deposit speeds were excessively high. In both the methods of McHale's Koguchicomo, the reported solution and the stoichiometries of the resulting film were identical. Conversely, in the CVD of the present invention, the stoichiometry of the solution may differ from the stereotyping of the desired film. Additionally, the droplet size resulting from the sprayed solutions was excessively large and the vapor pressure too low for an effective vapor deposition. A nebulized solution of precursors has been used with a plasma torch in a process called "inductively coupled plasma by spraying" ("spray-CIP" or "ICP"). See M. Kawaga, M. Kikuchi, R. Ohno and T. Nagae, J. Amer, Wax. Soc., 64, 1981, C7. In ICP spraying, a solution containing the reagents is atomized into fine droplets of 1-2 mm in diameter which is then carried in an ICP chamber. This can be considered as a plasma CVD process, different from flame pyrolysis. See M. Suzuji, M. Kagawa, Y. Syono, T. Hirai and K. atanabe, J. Materials Sci., 26, 1991, p. 5959-5932.

P1082 / 98MX These films of the oxides of Ce, La, Y, Pr, Nd, Sm, Cr, Ni, Ti, Zr, La-Sr-Cu, Sr-Ti, Zn-Cr, La-Cr, and Bi- Pb-Sr-Ca-Cu have been successfully deposited using this technique. See M. Suzuki, M. Kagawa, Y. Syono and T. Hirai, Thin films of Chromium Oxide Compounds Formed by the Spray-ICP Technique, J. Crystal Growth, 99, 1990, p.611-615 and M. Suzuki, M. Kagawa, Y. Syono and T. Hirai, Thin films of Rare, Earth (Y. La, Ce. Pr, Nd, Sm) Oxides Formed by the spray-ICP Technique, J. Crystal growth, 112, 1191, p. .621-627. Sustaining the substrate at an appropriate range from the plasma was crucial for the synthesizing density formulas. The range of desired deposition distances from the plasma source was small due to the rapid temperature drop of the gases. CVD type coatings were achieved using 0.5-1.0 M ultrasonically atomized solutions of metal nitrates in water that were fed into the ICP at 6-20 ml / hr using Ar flowing at 1.3-1.4 1 / min. Only oxides were deposited and liquid or liquid-like solutions almost at supercritical temperature were not used. The use of near-supercritical atomization with ICP was not considered in this comprehensive review of ICP nebulization techniques. See. T. R. Smithg and M. B. Denton, Evaluation of Current Nebulizers and Nebulizer Characterization Techniques, Appl. Spectroscopy, 44, 1990, p.21-4.

P1082 / 98MX Therefore, it is highly desirable to be able to form nanopowders and coatings at low production and capitalization costs and with simple production processes. It is also desirable to be able to form coatings in the open atmosphere without any expensive furnace, vacuum or reaction chamber. Additionally, it is highly desirable to provide a coating process that provides high adhesion to the substrate, controlled microstructure, flexibility, reduced raw material consumption and a reduced effect on the characteristics and / or dimensions of the coating system operation as long as it is capable of maintaining the highly desirable sub-micron capabilities that are important in obtaining an improved coating and dusting. Furthermore, it is highly desirable to provide a process that uses solutions almost at the supercritical point, and therefore, achieves excellent results below the melting point of the coating materials.

SUMMARY OF THE INVENTION The present invention satisfies these needs and defines the plasma torch and the films formed by steam produced by CCVD, nanofase powders and coatings from quasi-supercritical liquids and fluids.

P1082 / 98MX supercritical. Preferably, a fluid of liquid solution or similar to the liquid containing the chemical precursor (s) is formed. The solution fluid is regulated at almost or above the critical pressure and then heated to near supercritical temperature just before it is released through a nozzle restriction which results in a highly vaporized atomized solution fluid. Finely, dragged the gas. The vapor of the solution fluid is burned to form a flame or is introduced into a flame or electric torch plasma, and the precursor (s) reacts to the desired phase in the flame or plaster or on the surface of the substrate. Due to the high plasma temperature much of the precursor will react before the surface of the substrate. A substrate is placed almost on the electric flame or plasma, and a coating is deposited. Alternatively, the formed material can be collected as a nanophase powder. The method of the present invention provides very fine atomization, nebulization, vaporization or gasification by using solution fluids almost or above the critical pressure and near the critical temperature. The dissolved chemical precursor (s) do not need to have high vapor pressure, but the high vapor pressure precursors can work well or better than the precursors with a lower vapor pressure. By heating the fluid of P-1082 / 98MX 1 solution just before or at the end of the nozzle or restriction tube (atomization device), the time available for the reaction or chemical dissolution of the precursor before atomization is minimized. This method can be used to deposit coatings from various methanol-organic and inorganic precursors. The solvent of the fluid solution can be selected from any liquid or supercritical fluid in which the precursor (s) can form a solution. The liquid solvent or fluid may itself consist of a mixture of different compounds. A reduction in the supercritical temperature of the fluid containing the reagents demonstrated superior coatings. Many of these fluids are not stable as liquids to STP, and must be combined in a pressure cylinder or at a low temperature. To facilitate the formation of the fluid liquid solution that can only exist at pressures greater than the environments, the chemical precursor (s) are optionally first dissolved in a primary solvent that is stable at ambient pressure.

This solution is placed in a container capable of withstanding pressure and then the liquid or secondary fluid is added (or main) (in which the primary solution is visible).

The liquid or main fluid has a lower supercritical temperature, and results in a decrease P1082 / 98MX of the maximum temperature required for the desired degree of nebulization. By forming a primary solution of high concentration, much of the resulting lower concentration solution is composed of secondary and possibly additional solution compounds. In general, the higher the ratio of a given compound in a given solution, the more will be the properties of the solution that behaves like that compound. These additional liquids and fluids are chosen to assist in the atomization, vaporization or gasification of the solution containing the chemical precursor (s). The choice of a final solution mixture with low supercritical temperature further minimizes the occurrence of the chemical precursors that react within the atomization apparatus, as well as a decrease or elimination of the need to heat the solution in the release area. In some cases, the solution can be cooled before the release area so that the solubility and stability of the fluid is maintained. An expert in the technique of supercritical fluid solutions could determine several possible solution mixtures without undue experimentation. Optionally, a pressure vessel with a glass window or with optical fibers and a monitor, allows the visual determination of the visibility and capacity of solute-solvent. Contrarily, if the filters are reached P1082 / 98MX to be capped or precipitated remaining in the main container, an incompatibility may have occurred under those conditions. The size of the resulting powder produced by the methods and apparatus of the present invention can be decreased, and therefore, improved by: 1) decreasing the concentration of the initial solution; 2) decrease the time in hot gases; 3) decrease the size of the droplets formed; and / or 4) increasing the vapor pressure of the reagent used; each of the variables has other considerations. For example, economically, the concentration of the initial solution should be maximized to increase the rate of formation, and the low vapor pressure reagents should be used to avoid the high costs of many high vapor pressure reagents. The decrease of time in the hot gases, are opposed by the minimum required time of formation of the desired phase. The decrease in the size of the droplets formed can cause an increased temperature of the fluid which is opposed by the possible reaction of the fluid and the effects of dissolution. Similarly, the formation of the coating has parallel effects and relationships. Another advantage is that the release of the fluids almost or above their supercritical point results in P1082 / 98 X a rapid expansion that forms a high velocity gas-vapor stream. The high velocity gas streams effectively reduce the boundary layer of gas diffusion in front of the reservoir surface which, in turn, improves the quality of the film and the efficiency of the reservoir. When the velocities of the current are above the flame velocity, a pilot fire or other means of ignition should be used to form a steady-state flame. In some cases two or more pilots may be needed to ensure complete combustion. With the plasma torch, pilot lights are not needed, and high speeds can easily be achieved by following the operating connections known to those skilled in the art. The solute-containing fluid does not need to be the fuel for combustion. Non-combustible fluids similar to water or C02, or fluids difficult to burn similar to ammonia, can be used to dissolve the precursors or they can continue as the compound of the secondary solution. These are then spread on a plasma torch or flame that provides the environment for the precursors to react. The deposits can be made above, below or at ambient pressure. Plasma torches work well at reduced pressures. Flames can be stable below 10 torr, and P1082 / 98MX operate well at high pressures. Cold flames of even less than 500 ° C can be formed at lower pressures. While both may operate in open atmosphere, it may be advantageous to practice the methods of the invention in a reaction chamber under a controlled atmosphere to prevent air impurities from being entrained in the resulting coating. Many electrical and optical coating applications require that these impurities are not present in the coating. These applications normally require thin films, but thicker films for thermal barrier, corrosion and wear applications can also be deposited. You can put additional bulk material, including individual crystals, by extending the deposit time even more. The faster epitaxial deposition rates provided by the higher deposition temperatures, due to the high diffusion rates, may be necessary for depositing thick films of individual crystals or bulk material. Additional advantages of the invention will be set forth in part in the description that follows, and in part will be obvious from the description, or may be learned by practice of the invention. the advantages of the invention will be realized and achieved by means of the elements and combinations indicated particularly in the P1082 / 98MX appended claims. It will be understood that both the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the invention, as claimed.

BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 shows a schematic diagram of the apparatus of the invention. Figure 2 shows a schematic diagram of an apparatus for depositing films and powders using supercritical and almost supercritical atomization. Figure 3 shows a schematic, detailed view of the atomizer used in the present invention.

DETAILED DESCRIPTION OF THE PREFERRED MODALITIES The present invention can be more easily understood by reference to the following detailed description of the preferred embodiments of the invention and the figures. Before the present methods and apparatuses are described and detailed, it is to be understood that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting. It should be noted that, as used in the specification and the appended claims, the P1082 / 98MX singular forms "a", "an" and "the" include plural preferences unless the context clearly dictates otherwise. Throughout this application, where references are made to publications, the descriptions of these publications in their entireties are thus incorporated by reference in this application so that the state of the art to which this invention pertains is more fully described. The present invention provides a method for coating a substrate with a selected material. The method comprises, at a first selected temperature a selected first pressure, dissolved in a suitable carrier to thereby form a transport solution, one or more reactants capable of reacting (where, for an individual precursor reagent, the precipitation of a reagent from the solution is considered herein as a "reaction") to form the selected material. Sometimes before the actual deposit, a substrate is placed in a region having a second selected pressure. The second pressure selected can be the ambient pressure and is generally above 20 torr. The transport solution is then pressurized to a third selected pressure above the second selected pressure using a medium P1082 / 98MX of pressure regulator. One skilled in the art will recognize that there are many suitable pressure regulating means, including, but not limited to, compressors, etc. Then, the pressurized transport solution is directed to a fluid conduit having an inlet end and an opposite outlet end having a temperature regulating means positioned thereon to regulate the temperature of the solution at the end of the fluid. departure. The outlet end of the conduit additionally comprises an outlet orifice oriented to direct the fluid in the conduit to the region and in the direction of the substrate. The outlet orifice can be similar to a nozzle or limiter as used in other spraying and CVD applications. Subsequently, the solution is heated using a temperature regulating medium at a second selected temperature within 50 ° C above or below the critical temperature, Tc, of the solution while maintaining the third selected pressure above the second pressure selected and above the critical pressure or liquid phase, corresponding, Pc of the solution at the second selected temperature using the pressure regulating means. Then, the heated, pressurized solution is directed through the outlet orifice of the conduit to the region to produce a spray of nebulized solution in the direction of the P1082 / 98MX substrate. As the solution is directed to the region, one or more selected gases are mixed in the spray of nebulized solution to form a reactable spray, and subsequently, this reactable spray is exposed to a source of energy at a selected energization point. The energy source provides sufficient energy to react the reactable spray (which contains one or more reagents from the transport solutions) thereby forming the material and coating the substrate therewith. In a further embodiment of this method, the energy source comprises a flame source and the selected energization source comprises the ignition point. In an alternative embodiment, the energy source comprises a plasma torch. In a further embodiment of the method, the second pressure selected from the region is ambient pressure. In yet another embodiment, the spraying of the nebulized solution is a vapor or an aerosol having a maximum droplet size of less than 2 μm. In a further embodiment, the second pressure selected from the region is reduced to produce a combustion flame having a temperature of less than 1000 ° C. In yet another embodiment, the carrier is propane and the transport solution comprises at least 50% in P1082 / 98MX propane volume. In a further embodiment, the transport solution additionally includes butanol, methanol, isopropanol, toluene or a combination thereof. In yet another embodiment, the carrier is selected such that the transport solution is substantially free of precipitate at normal temperature and pressure for a period of time sufficient to carry out the method. In an alternative embodiment of the method, a pressurized container is used and before, during or after the pressurization step, a gas at normal pressure and temperature is also brought into contact with the transport solution at a selected pressure sufficient to form a liquid or supercritical fluid, (depending on the temperature). In a preferred embodiment, the transport solution containing the gas at normal temperature and pressure is substantially free of precipitate at the selected pressure for a sufficient period of time to carry out the method. In yet another embodiment, the concentration of the reagents of the transport solution is between 0.0005 M and 0.05 M. In a further embodiment, the outlet end of the conduit additionally comprises a fluid introduction port and, before directing the heated solution , pressurized through the exit orifice of the P1082 / 98MX conduit, fluid is added to the heated solution, pressurized through the fluid inlet hole. This introduction forms a combined solution having a directed supercritical temperature. In yet another embodiment, each of one or more reagents of a vapor pressure of not less than about 25% of the vapor pressure of the carrier. In a further embodiment, the outlet orifice of the conduit comprises the pipe having an internal diameter of 2 to 1000 μm, preferably 10 to 250 μm. in a more preferable embodiment, the outlet end of the conduit comprises the pipe having an internal diameter of 25 to 125 μm. In yet a further preferable embodiment, the outlet end of the conduit comprises the pipe having an internal diameter of 50 to 100 μm. In another embodiment, the temperature regulating means comprises means for resistively heating the conduit by applying thereto an electric current of a selected voltage from an electric current. In a preferred embodiment, the voltage is less than 115 volts. In yet another preferred embodiment, the means for resistively heating the conduit comprises a contact placed in the 4 mm space of the outlet orifice. Additionally, the present invention also P1082 / 98MX provides the above method where the carrier and one or more reagents are selected such that the second temperature selected is the ambient temperature. The above method can be practiced where the material coating the substrate comprises a metal. Alternatively, the material coating the substrate comprises one or more metal oxides. In an alternative, additional embodiment, the material coating the substrate comprises a carbonate, a sulfate, or a phosphate. In yet a further embodiment, the material coating the substrate comprises at least 90% silica. In a further embodiment, the reactable spray comprises a fuel spray having a fuel spray speed and wherein the fuel spray rate is greater than the flame rate of the flame source at the ignition point and comprising in addition one or more ignition aid means for igniting the fuel spray. In a preferred embodiment, each of the means or means of assisting the ignition comprises a pilot fire. In yet another mode, the speed of the fuel spray is greater than a mach. In a further embodiment, the ignition point no flame source is maintained within 2 cm of the exit orifice.

P1082 / 98MX The present invention also provides a method wherein, the exposure step, the cooling of the substrate is using a substrate cooling medium. In a preferred embodiment, the substrate cooling means comprises a means for directing water on the substrate. However, one skilled in the art will recognize that many other suitable cooling means could be used. In a further embodiment, the material coating the substrate comprises a carbon material. In another embodiment, the material coating the substrate comprises diamond. In an alternative embodiment, the material coating a substrate comprises one (1) diamond and (2) a metal or metal oxide. In a further embodiment, the material covers the substrate with a thickness of less than 100 nm. In yet another embodiment, the material that covers a substrate comprises a graduated composition. In another embodiment, the material that covers a substrate comprises an amorphous material. In a further embodiment, the material coating a substrate comprises a nitride, carbide, boride, metal or other material that does not contain oxygen. The present invention also provides a method that further comprises flowing a selected shell gas around the reactable spray, P1082 / 98MX thereby decreasing entrained impurities and maintaining a favorable deposit environment. In a preferred embodiment, the second selected pressure is above 20 torr. In addition to the above methods, the present invention also provides an apparatus for coating a substrate with a selected material. Referring now to Figure 1 the apparatus 100 comprises a pressure regulating means 110, such as a pump, for pressurizing at a selected first pressure, a transport solution T (also called "precursor solution") in a solution tank of transport 112, wherein the transport solution T comprises a suitable carrier having dissolved therein one or more reagents capable of reacting to form the selected material and wherein the means for pressurizing 110 is capable of maintaining the first pressure selected by above the liquid phase pressure (if the temperature is below Tc) or critical, corresponding, PC / of the transport pressure T to the temperature of the transport solution T, a fluid conduit 120 having an end of inlet 122 in fluid connection with the reservoir of the transport solution 112 and an opposite outlet end 124 having an outlet orifice 126 oriented to direct the fluid in conduit 120 in a region 130 of the second pressure P1082 / 98MX selected below the first selected pressure and in the direction of the substrate 140, where the exit orifice 126 further comprises a means 128 (see Figures 2 and 3, atomizer 4) to nebulize a solution to form a spray N of nebulized solution, a temperature regulating means 150 placed in thermal connection with the outlet end 124 of the fluid conduit 120 for regulating the temperature of the solution at the outlet end 124 within 50 ° C above or below the supercritical temperature Tc of the solution, a gas supply means 160 for mixing one or more gases (eg, oxygen) (not shown) in the spray N of the nebulized solution to form a reactable spray, an energy source 170 in a selected energizing point 172 for reacting the reactable spray, whereby the energy source 170 provides sufficient energy to react the Reactable spray in the region 130 of the selected second pressure, thereby coating the substrate 140. In a further embodiment of the apparatus, the energy source 170 comprises a flame source and the energization point 172 comprises an ignition point. In an alternative embodiment, the energy source 170 comprises a plasma torch. In yet another mode, the hole Output P1082 / 98MX 126 further comprises a pressure restriction (see Figure 3, limiter 7). In a further embodiment of the apparatus, the second pressure selected from the region is ambient pressure. In yet another embodiment, the spray N of the nebulized solution is a vapor or an aerosol having a maximum droplet size of less than 2 μm. In a further embodiment, the second pressure selected from the region is reduced to reduce a combustion flame having a temperature of less than 1000 ° C. In yet another embodiment, the carrier is propane and the transport solution comprises at least 50% by volume of propane. In a further embodiment, the transport solution additionally includes butanol, methane, isopropanol, toluene or a combination thereof. In yet another embodiment, the carrier is selected such that the transport solution is substantially free of precipitate, the normal pressure temperature for a period of time sufficient to carry out the method. In an alternative embodiment of the apparatus, a pressurized container (not shown) is provided and a gas at normal temperature and pressure is also brought into contact with the transport solution at a pressure P1082 / 98MX selected enough to form a liquid or supercritical fluid. In a preferred embodiment, the transport solution containing a gas at normal temperature and pressure is substantially free of precipitate at the selected pressure for a period of time sufficient to carry out the method. In yet another embodiment, the reagent concentration of the transport solution is between 0.0005 M and 0.05 M. In a further embodiment, the outlet end 124 of the conduit 120 further comprises a fluid introduction port (see Figure 2, feed 17 to 19) and before directing the heated solution, pressurized through the outlet orifice 126 of the conduit 120, the fluid is added to the heated, pressurized pressure through the fluid introduction port. This introduction forms a combined solution having a reduced supercritical temperature. In yet another embodiment, each of one or more reagents has a vapor pressure of not less than about 25% of the vapor pressure of the carrier. In a further embodiment, the outlet orifice of the conduit comprises a pipe having an inner diameter of 2 to 1000 μm, preferably 10 to 250 μm. In a more preferable mode, the exit end P1082 / 98MX of the conduit comprises a pipe having an internal diameter of 25 to 125 μm. In still a modality, further, the outlet end of the conduit comprises a pipe having an internal diameter of 50 to 100 μm. In yet another embodiment, the temperature regulating means 150 comprises a means for resistively heating a conduit by applying an electrical current to an assembly selected from an electric current source. In a preferred embodiment, the voltage is less than 115 volts. In yet another embodiment, the means for resistively heating a conduit comprises a contact 152 positioned within 4 mm of the outlet orifice 126. In addition, the present invention also provides the above apparatus wherein the carrier and one or more reagents are selected such that the second temperature selected is room temperature. The above apparatus can be used wherein the material coating the substrate 140 comprises a metal. Alternatively, the material coating a substrate 140 comprises one or more metal oxides. In an alternative, additional embodiment, the material coating the substrate 140 comprises a carbonate, a sulfate or a phosphate. In yet a further embodiment, the material coating the substrate 140 comprises a carbonate, a sulfate P1082 / 98MX or a phosphate. In yet a further embodiment, a material coating the substrate 140 comprises at least 90 ° of silica. In a further embodiment, the reactable spray comprises a fuel spray having a fuel spray speed and wherein the fuel spray rate is greater than the flame rate of the flame source at the ignition point 172 which further comprises one or more 180 ignition aid means to ignite the fuel spray. In a preferred embodiment, each of one or more ignition aid means 180 comprises a pilot fire. In yet another mode, the fuel spray speed is greater than a mach. In an additional mode, the ignition point 172 or flame front is maintained in the space of 2 cm from the exit orifice. The present invention also provides a substrate cooling means 190 for cooling the substrate 140. In a preferred embodiment, the cooling medium of the substrate 190 comprises a means for directing water on the substrate 140. However, one skilled in the art will recognize that many other suitable cooling means could be used. In an additional modality, the material that P1082 / 98MX reduces the substrate 140 comprising a carbonic material. In another embodiment, the material coating the substrate 140 comprises diamond. In an alternative embodiment, the material coating the substrate 140 comprises (1) diamond and (2) a metal oxide or a metal. In a further embodiment, the material coating the substrate 140 has a thickness of less than 100 n-m. In yet another embodiment the material coating the substrate 140 comprises a graduated composition. In another embodiment, the material coating the substrate 140 comprises an amorphous material. In a further embodiment the material coating the substrate 140 comprises a nitride, carbide, bururo, metal or other material that does not contain oxygen. The present invention also provides an apparatus further comprising a means (see Figures 2 and 3, feed line 17 or 19) for flowing a selected shell gas with reactable spray radiator, thereby decreasing entrained businesses and maintaining a favorable deposit environment. In a preferred embodiment, the second selected pressure is above 20 torr. In addition, the present invention also provides a method for creating a powder material of a region. This method of dusting comprises, at first P1082 / 98MX selected temperature and a selected first pressure, dissolve in a suitable carrier to thereby form a transport solution one or more reactants capable of reacting to form the powder material or in the region, wherein the region has a second pressure selected lower than the first selected region. The powder formation method then comprises pressurizing the transport solution or a third pressure selected above the second selected pressure using a pressure regulator means. Subsequently, the pressurized transport solution is directed to a fluid conduit having an inlet end and an opposite outlet end having a temperature regulating means placed therein to regulate the temperature of the solution at the outlet end , wherein the outlet end further comprises an outlet orifice oriented to direct the fluid in the conduit in the region. The solution is then heated using the temperature regulating medium at a second selected temperature within 50 ° C above and below the critical temperature, Tc, of the solution while maintaining the third selected pressure above the second pressure selected and above the corresponding liquid or critical phase pressure, Pc, of the solution at the second selected temperature using the regulating medium of P1082 / 98MX pressure. The heated, pressurized solution is then directed through the outlet orifice of the conduit in the region to produce a spray and nebulized solution. One or more selected gases are mixed in the spray of the nebulized solution to form a reactable spray. Finally, the reactable spray is exposed to a source of energy at a selected energization point whereby the energy source provides sufficient energy to react the reactable spray thereby forming the powder material in the region. In a further embodiment of the method, the energy source comprises a flame source and the selected energization point comprises an ignition point. In an alternative embodiment, the energy source comprises a plasma torch. In a further embodiment, a powder formation method can be used to coat a particular substrate. For this method, the above method is modified such that the method further comprises mixing a substrate material selected by the transport solution. In a preferred embodiment, additional to the powder formation method, the concentration and the transport solution is between 0.005 M and 5 M.

P1082 / 98MX In another embodiment, the present invention provides an apparatus for creating a material in powder form, comprising a pressure regulating means for pressurizing at a first selected pressure to a transport solution in a transport solution tank, in wherein the transport solution comprises a suitable carrier having dissolved therein one or more reagents capable of reacting to form the selected material and wherein the means for pressurizing is capable of maintaining the first selected pressure above the liquid phase pressure or critical, Pc, corresponding to the transport solution at the temperature of the transport selection, a defined conduit having an inlet end in fluid connection with the transport solution reservoir and an opposite outlet end, which has a outlet orifice oriented to direct the fluid in a duct in the direction of a region of a second pressure n selected less than the first pressure selected, wherein the outlet orifice comprises a means for nebulizing a solution to form a spray of nebulized solution, a temperature regulating means placed at the outlet end of the fluid conduit to regulate the temperature of the solution at the outlet end, a gas supply means for mixing one or more gases in the solution spray P1082 / 98MX nebulized to form a reactable spray, and a source of energy at a selected energization point to react the reactable spray, whereby the energy source provides enough energy to react the reactable spray in the region of the second selected pressure, thereby forming the powder material. The apparatus is similar to the coating apparatus, except that no substrate is placed in the region, and instead, the dust is collected. In addition, the present invention provides a coating on a substrate produced by the process described above. In addition, the present invention provides a powder produced by the process described above. A flame requires that an oxidant be present. In this way, materials that are not stable in the presence of oxidants can not be formed using a flame. See, C.H.P. Lupis, "Chemical Thermodynamics of Materials", Elsevier Science Publishing, 1993. Instead, these materials are deposited using a plasma torch. When using a plasma torch, a shell gas, a plasma enclosing tube, and / or a reaction chamber is necessary to maintain an environment free of air and oxidants. Due to the instability in the P1082 / 98MX presence of oxidants, the fluid and gases used must not contain oxidizing elements. Additionally, the use of hydrocarbon compounds can result in the deposit of extensive carbon. While some carbon is needed for the formation of carbons, too much carbon can result in coatings with a high carbon content and possibly elemental carbon. In these cases, the concentration of the solution must be increased, or a fluid that is free of carbon or has a low carbon content must be used. An expert in the combustion technique can determine, with only routine experimentation, the adjustments that will minimize the deposition or incorporation of the elemental carbon. This deposit is also called "embedding" or "carbon accumulation" in the burner and machine applications. For the deposit of nitrides, a plasma torch should be used, and ammonia is one of the appropriate torches. Metal films can be deposited from chemical systems with no or low concentration of anions from thermodynamically stable phases. In a brief example, if the metal Ti was desired, then the concentration of C, N, and B will be preferably low, and there will be almost no compounds containing Cl, F or O. When the plasma torch is used, it is more easy to deposit stable materials to oxygen because the gas jacket or tube Enclosure P1082 / 98MX does not need to be used. However, the cost of materials deposited and formed by flames is lower, and thus is preferred for thermodynamically stable materials in environments that contain enough oxygen to maintain a flame. It may be desired to form a coating completely or partially composed of elemental carbon, in which case all compounds containing elemental oxygen and reactive oxygen must be kept separate from the carbon film while the temperature of the film is such that the oxidation of the carbon is thermodynamically favored over the presence of elemental carbon. If fatty amounts of oxygen are present, it can be made to the more reducing reaction atmosphere by supplying elemental hydrogen. Diamond and diamond-like carbon coatings can be deposited from a flame containing oxygen, and the necessary deposit conditions are known to those skilled in the art. The addition of dopant or a second phase to the carbon coating can be achieved by adding a reagent to the flame or plasma by the use of this present invention. To simplify the operation, it is useful to pump the precursor / solvent solution to the atomization device at room temperature. The heating of the P1082 / 98MX solution should occur as a final step just before releasing the solution in the low pressure region. This final stage of heating minimizes the reactions and immiscibilities that occur at high temperatures. The maintenance of the solution below the supercritical temperature until the authorization keeps the dissolved amounts of the precursor in the region of normal solubility and reduces the development potential of significant gradients of concentration of solvent-precursor in the solution. These safety gradients are a result of the sensitivity of the concentration of a supercritical solvent solution or compression. Low pressure gradients (as they may develop along the distribution of the solvent-precursor system) can lead to significant changes in solubility as observed. For example, the solubility of acridine in carbon dioxide at 308 ° K can be increased 1000 times by increasing the pressure from 75 atm to 85 atm. See V. Krukonis, "Supercritical Fluid Nucleation of Difficult to Comminute Solids", presented at AIChE Meeting, San Francisco, November 25-30, 1984. These solubility changes are potentially harmful because they can cause the precursor to get out of control. solution and precipitate or react prematurely, blocking the lines and filters.

P1082 / 98MX The rapid drop in pressure and the high velocity in the nozzle causes the solution to spread and atomize. For solute concentrations in the normal range of solubility, preferred for the operation of the near-supercritical atomization system of the present invention are the precursors that are still effectively in solution after they are injected into the low pressure region. The term "effectively in solution" must be understood in conjunction with the processes that take place when the solution with solute concentrations above the normal concentration of solvents is injected into the low pressure region. In this case, the sudden pressure drop causes high supersaturation ratios responsible for the catastrophic solute nucleation conditions. If the catastrophic nucleation rapidly depletes the solvent of the entire dissolved precursor, the proliferation of the small precursor particles is improved. See, D.W. Matson, J.L. Fulton, R.C. Petersen and R.D. Smith, "Rapid, Expansion of Supercritical Fluid Solutions: Solute Formation of Powders, Thih Films, and Fibers", Ind. Eng. Chem. Res., 26, 2298 (1987); H. Anderson, T.T. Kodas and D.M. Smith, "Vapor Phase Processing of Powders: Plasma Synthesis and Aerosol Decomposition", Am. Wax. Soc. Bull., 68, 996 (1989); C.J. Chang and A.D. Randolph, "Precipitation of Microsize Organic Particles from Supercritical Fluids", AIChE Journal, 35, P1082 / 98MX 1876 (1989); T.T. Kodas, "Generation of Complex Metal Oxides by aerosol Processes: Superconducting Ceramic Particles and Films", Adv. Mater., 6, 180 (1989); E. Matijevic, "Fine Particles; Science ad Technology", MRS Bulletin, 14, 18 (1989); E. Matijevic, "Fine Particles Part II: Formation Mechanisms and Applications", MRS Bulletin, 15, 16 (1990); R.S. Moha ed, D.S. Haverson, P.G. Debenedetti and R.K. Prud'homme, "Solid Formation After Expansion of Supercritical Mixtures," in Supercritical Fluid Science and Technology, edited by K.P. Johnston and J.M.L. Penniger, p. 3355, American Chemical Society, Washington, DC (1989); R.S. Mohamed, P.G. Debenedetti and R.K. Prud'homme, "Effects of Process Conditions on Crystals Obtained from Supercritical Mixtures", AIChE J., 35, 325 (1989); J.V. Tom and P.G. Debenedetti, "Formation of Bioerodible Polymeric Microspheres and Microparticles by Rapid Expansion of Supercritical Solutions", Biotechnol. Prog., 7, 403 (1991). The particles are undesirable for the formation of thin coatings, but may be beneficial during the formation of powders. In this way, the heated atomizer of the present invention provides the additional, superior advantages, compared to an unheated device operating in rapid expansion of a solvent exclusively above the supercritical temperature, which (1) P1082 / 98MX temperature allows a well controlled degree of atomization of the precursor-solvent mixture and (2) catastrophic nucleation of the precursors can be avoided while still discussing the benefits of supercritical atomization. You can create supersonic speeds that form a mach disk that additionally benefits atomization. By adjusting the heat input of the atomization device, the liquid solution can be evaporated to several degrees. Without heat input to the atomization device, the liquid solutions of the higher supercritical temperature liquids, which are the liquids at STP, may come out in the form of a liquid stream that is clearly far from a supercritical condition. This result in a poorly formed flame and possibly an initial liquid contact with the substrate. Diminishing the temperature differential of the liquid solution at its supercritical temperature at the nozzle causes the liquid solution to melt into droplets forming a mist that is released from the atomization device. The droplets evaporate, and in this way they become invisible, after a short distance. As the supercritical temperature of the atomization device is reached, the droplets of the liquid solution decrease in size and the distance to the evaporation of the P1082 / 98MX solution. Using this atomizer, the size of the vapor droplets was determined using an aerosol vaporization tester and the size obtained from the droplets was below the detection limit of 1.8 mm of the instrument. The additional increase in heat input results in a state of non-fog at the tip, or full vaporization. Without wishing to be joined by a goal, this behavior of the solution can be attributed to the combined supercritical properties of the reactants and solvents. Solutions of precursors in lower supercritical temperature solvents, which are gases to STP, behave similarly, but the emerging solution of the tip (also referred to as the "nozzle" or "limiter") does not form a liquid stream, yet without heat input. The amount of heat necessary to obtain the optimum evaporation of the solution depends mainly on the heat capacity of the solution and the differential between the supercritical temperature of the solvent and the ambient temperature around the nozzle. It is desirable to maintain the pressure and temperature of the system (before vaporization) above the boiling and supercritical point of the solution. If the pressure falls below the liquid or critical phase pressure, coinciding with the temperature above the boiling point, the evaporation of the solvents will occur in.

P1082 / 98MX the tube before the tip. This leads to solutes that can accumulate and clog the atomization device. Similarly, the pressure is preferably sufficiently high in the supercritical region, so that the fluid is more liquid-like. Liquid-like supercritical fluids are better solvents than more gas-like supercritical fluids, further producing the likelihood of solutes becoming clogged in the atomization device. If the precursor to precursor interaction is high is higher than the concentration between the concentration between the solvent and the precursor, the solvent-precursor bonds can be broken and the solution's precursor output is effectively driven. The precursor molecules then form aggregates that adhere to the atomization device and plug the indicator. The problem can be solved, in most cases, by changing the evaporation point from the inside of the tip to the end of the tip, which is achieved by reducing the heat input in the atomization device. Another solution is to use a solvent that forms stronger bonds with the precursor so that a more stable solution is formed. A small amount of fog at the tip usually results in thin films of better quality. Nano- or microspheres of the material will form if the temperature of the P10T2 / 98MX solution is too high or too low. These spheres are detrimental if dense coatings are desired. If a fog condition is not reached, the deposit is being made above the critical temperature. The heat of the flame and the mixture with external gases keep the solids liquids of STP out of the condensation and formation of droplets. In the case of no fog, atomization and intermixing is very good but the stability of the flow is reduced, resulting in a flame that can jump from side to side with respect to the direction of the tip. With this behavior of the flame, the deposits remain possible, but it can be difficult to deposit films that require a more severe thickness uniformity. Additionally, it is necessary to maintain the temperature of the solution, before release, below the temperature where either the solute precipitates or reacts and precipitates. When a mixture of solvents is used, it may be possible during heating to use the line for spinoidal immiscibility. This causes the formation of two separate phases, with the possibility of concentration differences in the two phases due to different solubilities of the solutes. This can influence the information of the precursor and the product spheres at high atomization temperatures. All these factors P1082 / 98MX demonstrate the preferableness of minimizing the exposure of the solution to heating, if necessary, to the tip, so that they do not have enough time to occur, possible, unwanted, equilibrium condition matter states. The structure of the deposited films can thus be controlled precisely. Due to this control, the number of film microstructures is possible. By increasing the concentration of the solution, it is possible to increase the deposition rate and the following microstructural changes result with the increase of the concentration of the solution; dense to porous, specular to dull, soft to strong, column to mounds, and thin to thick. Graduated and multilayer coatings can also be produced. See, Example VI. The various layers can be formed by supplying different solutions containing precursors to an individual flame. Multiple sequential reservoir flames can be used to increase performance for production applications. Some additional factors that control deposit parameters include; the temperature of the surface of the substrate that controls the diffusion and surface nucleation, the pressure that controls the thickness of the boundary layer and in this way the speed of P1082 / 98MX deposit, the composition of the solution and the mixing gases vary the material that is deposited and in this way the habit and development of coatings, flame and plasma energy level affect where the reaction and vapor stability occurs , and the distance to the substrate affects the nebulization time for the reaction to the deposit that can lead to the formation of particles, or an increased diffusion time for larger aggregates. Additionally, electric and magnetic fields affect the development habits of these materials, or increase the deposit efficiency. One skilled in the art will recognize that electric and magnetic fields will affect the development habits of some materials deposited by steam, as well as the particular rate of deposit and efficiency will vary. Because the input of energy required in the solution heating the atomizer varies for different solutions of precursor / primary solvent / secondary solvent, it is preferred to deposit thin multilayer films from solutions with constant ratios of primary to secondary solvent. In doing so, it is not necessary to change the energy input to the atomizer when changing from one solution to another solution. The resulting simplification of the adjustment produces improved performance and reliability that reduce costs.

P1082 / 98MX Alternatively, the substrate can be passed through flames containing different reagents to accumulate the desired multilayer. A major difference between the use of flame fluids and plasma fluids is that, frequently, the concentrations of the flame solution must be related to the desired flame energy level. High concentrations of the solution can lead to porous coatings or plugging of the tube. More diluted solutions, precursors with higher vapor pressure, higher deposition temperatures and / or compounds with a deposit with high mobility and diffusion, require less heating of the solution fluid to achieve dense coatings. Low vapor pressure precursors can form high quality coatings, but the spray and deposit parameters have less variability than is possible for reagents with a high vapor pressure. However, low solution concentrations produce unacceptably low deposit rates. When the solution provides fuel for combustion, concentrations of up to 0.1 molar result in dense coatings depending on the material. Most materials have preferred concentrations of up to 0.01 molar. The P1082 / 98MX materials with less diffusion and mobility need solution concentrations of less 0.002. Solution concentrations of 0.0001 molar result in very slow deposit rates for most materials. Deposits by plasma torch and flame with added fuel materials may have higher concentrations, even exceeding 1 M, but for the preferable vapor formation of the precursors, high concentrations are less desirable unless in the precursor (s) have high vapor pressures. The solution concentrations of the low vapor pressure precursor are preferably less than 0.002 molar. Without wishing to have any theory, it is It is useful to understand that the principle of the reservoir technique of the present invention comprises the finding that CVD is not limited to surface reactions. See, Hunt, A.T., "Chemical Combustion Vapor Deposition, at Novel Thin Film Deposition Technique", Ph.D. Thesis Georgia Inst. Of Tech, Atlanta, GA., (1993); Hunt, A.T., "Presubstrate Reaction CVD, and a Definition for Vapor", presented at the 13th Int. Conf. On CVD, Los Angeles CA. (1996), the contents of which are incorporated herein by reference. Reactions can occur predominantly in the gas stream, but the material The resulting P1082 / 98MX that is deposited must be subcritical in size to produce coating with vapor deposited microstructures. These observations demonstrate that a vapor is composed of individual atoms, molecules or nanoaggregates that can be absorbed in a substrate and easily diffused in low energy sites or low energy configurations. In this way, the maximum size of the aggregate should decrease with lower substrate temperatures since as the size of the critical core does. It is known to one skilled in the art that the reagent aggregates are left after evaporation of the solvents, and the size of the aggregate is related to the vapor pressure of the reagent, initial size of the droplets and solution concentration. Therefore, the atomization of the low vapor pressure reagents, which do not therefore vaporize in the flame, must be very fine. Preferred liquid solvents are less expensive solvents including, but not limited to ethanol, methanol, water, isopropanol and toluene. The water solutions must be fed into a pre-existing flame, while the combustible solvents must be used by themselves to form the flame. It is preferred, but not required, to form the volume of the flame using the solution instead of feeding the solution into a flame. The P1-082 / 98MX lower concentration of the reagents results in this way, which facilitates the formation of materials with a subcritical core size. A secondary solution fluid of the preferred solvent that is propane, which is a gas to STP. However, it should be noted that many solvent systems are operable. See, for example CRC Handbook of Chemistry and Physics, CRC Press, Boca Raton, Florida. Propane is preferred because of its low cost, commercial availability, and safety. After using many less expensive organometallics in a predominantly propane solution. For ease of handling, the initial precursors can be dissolved in methanol, isopropanol, toluene or other propane-compatible solvents. This initial solution is then placed in a vessel in which liquid propane is added. Propane is liquid above only about 100 psi at room temperature. The resulting solution has a much lower supercritical point than the initial solution that facilitates atomization by decreasing the input of energy required in the atomizer. Additionally, the primary solvent acts to increase the polar solubility of propane, thus allowing higher concentrations of solutions for many reagents that would otherwise be achieved by propane.

P1082 / 98MX only. As a general rule, the polarity of the primary solvent should be increased with the increase in the polarity of the solute (precursor). In this way, isopropanol can help in the solubility of a polar solute better than toluene. In some cases, the primary solvent acts as a shield between the secondary solvent and a ligand in the solute. An example is the dissolution of platinum-acetylacetonate [Pt (CH3COCHCOCH3) 2] in propane, the weight ratios between the precursor / primary solvent and primary solvent / secondary solvent may be higher than those required in other systems. Ammonia has been considered and tested as a secondary solvent for the deposit of coatings and powders. While ammonia is a cheap solvent that is not compatible with nitride-based precursors, it can not be easily used with other secondary solvents and problems arise from the general aggressiveness of pure ammonia. The atomization properties of the ammonia were tested without the addition of the precursor and the pressure vessel used was significantly attacked after the experiment even when an inert type 316 stainless steel vessel was used. In contrast to hydrocarbon-based solvents, ammonia also returns to the point of useless Viton and Buna-N after only a few minutes. Even with a suitable joint material this P1082 / 98MX is a problem since the desired coatings or powders usually do not contain traces of iron washed from the wall of the pressure vessel. Other gas-like secondary solvents that have been tested and can be used include ethane, ethylene, ethane / ethylene mixture, propane / ethylene mixture, propane / ethane mixture. Secondary ethane and ethylene solvents were used to coat individual glass, sapphire substrates with thin films of YSZ and YSZ-alumina resulting in dense films of good quality. Thin films of platinum were deposited from a supercritical mixture of ethane and a methanol-organic platinum. The thin films of LCS and PLZT were deposited from supercritical ethane mixtures. For these deposits, a non-heated nozzle was used such that the precursor solution was only subjected to rapid expansion atomization. A nozzle with a large ID ("internal diameter") (compared to the hole) with a small hole was used. Since the hole is only about 0.1 mm long (in the direction of the flowing precursor solution), the pressure gradient across the restriction or limitation approaches a discontinuous transition. This sudden pressure drop allows an adiabatic expansion of the solvent. The processes that take place in these systems do not P1082 / 98MX equilibrium, rapid expansion have been studied for several supercritical systems, see, for example, C.R. Yonker, S.L. Frey, D.F. Kalkwarf and R.D. Smith, "Characterization of Supercritical Fluid Solvents Using solvatochromatic Shifts," J. Phys, Chem., 90, 3022 (1986); P.G. Debenedetti, Homogeneous Nucleation in Supercritical Fluids ", AIChE J., 36 1289 (1990), JW Tom and PG Debenedetti," Particle formation with supercritical Fluids- A Reviewk ", J. Aerosol, Sci., 22, 555 (1991). Other solvents and solvent mixtures tested resulted in similar quality, but they were more complex to work with since their boiling points are significantly lower, requiring cooling of the solution.The ease of handling makes propane the preferred solvent but the other supercritical solvents are considered alternative to propane in cases where propane can not be used, such as when a precursor that is soluble in propane can not be found, other fluids can be used to further reduce the supercritical temperature if desired. used the propane / solvent fuel system to conduct studies on deposit velocity and deposit efficiency, and deposit efficiencies of 17% showed for the deposit of Si02 completely dense. The deposit speeds of 1 P1082 / 98MX μm / min were obtained for dense Si20. During the development experiments, it was established that a method of heating and applying an electric current between the end of the nozzle, where the precursor solution is injected into the low pressure region, and the upper part of the restriction tube. This method of directly heated restrictive tube allows rapid changes in atomization due to a fourth response period. The location of the most intense heating can be changed to the tip by increasing the connection resistance between the tip and the electrical conductor connected to the tip. The thin-walled restriction tubes have a greater distance than the thick-walled tubes and decrease the response time. Other heating methods can be applied and several have been investigated, including, but not limited to, resistive and far heating, pilot flame heating, inductive heating and laser heating. One of ordinary skill in the art can easily determine other suitable heating means for regulating the temperature in the outlet orifice of the atomizer. The resistive and far heating uses a non-conductive restriction tube that is located inside an electrically connected tube. The non-conductive tube is P1082 / 98MX will fit hermetically into the conductor tube. The application in an electric current to the conductor type heats and the tube and an energy is transferred into the non-conductive, internal restriction tube. This method requires higher heating currents compared to the restrictive and directly heated tube method and shows longer response times, which can be disadvantages under certain conditions since the increased response time results in a high degree of thermal stability. On the other hand, pilot flame and laser heating use the energy of the pilot flame or laser light, respectively, to heat the restriction tube. This can be done in a directly heated facility where the tip of the restriction tube is subjected to the pilot flame or laser light or in a directly heated configuration where a larger outer tube is heated. Because the amount of energy that needs to be transferred into the solution is completely large, the heated tube will preferably have a thicker wall than in the case of direct electric heating or far electrical heating. By submitting an outer tube to the pilot flame or laser light allows the use of a thin-walled restriction tube. Referring now to Figures 2 and 3, an apparatus 200 is shown for the deposit of films and P1082 / 98MX powders using supercritical atomization. The apparatus 200 consists of a fixed variable speed pump 1 which pumps the reagent transport solution 2 (also called "precursor solution") from the solution container 3 to the atomizer (also referred to as the "nebulizer" or "vaporizer"). 4. Figure 3 is an interleaving view showing a more detailed schematic view of the atomizer 4. The precursor solution 2 is pumped from the precursor solution container 3 through the lines 5 and the filters 6 and up to the Atomizer 4. The atomizer solution 2 is then pumped into a limiter 7 with controlled, variable or constant temperature. That can achieve heating in many ways, including, but not limited to, resistible electrical heating, laser heating, inductive heating, or flame heating. For resistive electrical heating, either AC or DC current can be used. One of the electrical connections 8 of the limiter 7 is preferably placed very close to the tip of the limiter 7. In the case of treatment by a CD bridge; this connection 8 or pole can be either positive or negative. The other pole 9 can be connected at any point along the limiter 7, inside or outside the housing 10. For special applications such as the lining of the interior of the tubes, where it is P1082 / 98MX advantageous a small overall size of the atomizer, it is preferred to connect either the limiter 7 to the rear of the housing 10 or to connect inside the housing 10. The gas connections in the rear part of the housing 10 are shown in an arrangement in line but can be placed in any other arrangement that does not interfere with the apparatus 200. Line 11 of gas supply A, thin, ID 1/16 inch in most cases, forms a mixture of combustible gases at an outlet small 12 which can serve as a stable pilot flame, preferably within 2.5 cm of the limiter 7, for combustion of the precursor solutions supplied via the limiter 7. The gas supply A is inspected by a flow controller 13, controlled the flow of the individual components of the gas mixture A, 14 and 15. The gas fuel component A are mixed with the oxidizing component 15 in a "T" mixture 16 near or inside the atomizer 4. This last mixture is preferably for security reasons because it reduces the potential feedback. The distribution channels 10 within the housing 10 connect the gas supply lines 11 to the gas supply 17. The gas supply lines B are used to distribute gas B from the supply 19 such that a good gas can be achieved. mix with P1082 / 98MX nebulized solutions. In most cases, a high-velocity gas stream is used. A number of gas supply holes B (4 four for most, more or less holes can be used depending on the particular application) is placed around the limiter 7 supplying the gas B such that the pattern is obtained desired flow. The flow properties and the gas stream B are influenced by factors such as the gas fraction B in the storage vessel 21 and gas B, the flow rate as determined by the flow controller 13, the diameters of line 5, and the number of supply holes 20. Alternatively, gas B can be fed through a large coaxial tube or surrounding restrictor 7. Once precursor solution 2 has pumped to precursor supply 22 its temperature is controlled by the current flow (in the case of electric heating) through the limiter 7 as determined by the power supply 23. This heating current can then be applied such that the appropriate amount of atomization can occur ( nebulization, vaporization). The stable pilot flame is then able to ignite the nebulized reactive spray and deposit a powder or film on a substrate 24. Many coatings have been deposited P1082 / 98MX using the methods and apparatus of the present invention. While propane is used in most cases as the supercritical secondary solvent (ie, a small amount of the primary solvent of high concentration of precursor was mixed with a large amount of primary solvent) Other solvents have been used Other secondary solvents Possible include, but are not limited to, ethylene, ethane and ammonia The following is a list of materials deposited to date using the apparatus of Figure 2 and only represents a few of the many possible materials that can be deposited using the present invention This list is not intended to limit the scope of the present invention as set forth in the META claims: Ag, Au, Cu, Ni, Pt and Rh Oxides: A1203, 3Al203-2Si02, BaCe03, BaTi03, BST, Cr203 , Cu20, DLC, l20, (K) -Si02, LaP04, LSC, LSM, MgO, MnO-Pt, NiO, PbS04, PdO, PLZT, PZT, Ru02, Si02, Sn02, SrLaAl04, SrTi03, Ti02, Yba2Cu30x, YIG , YSZ, YSZ-alumina (ZTA), Y203 and Zr02 OTHERS: BaC02, LaP04, and PbS04 One skilled in the art would recognize that almost any substrate can be coated by the method and apparatus of the present invention. It can be coated P1082 / 98MX substrate if it can withstand the temperature and conditions of the reduced hot gases produced during the process. A substrate can be cooled using a means for cooling (described elsewhere herein), such as a water jet, but at low substrate surface temperatures, dense or crystalline coatings of many materials are not possible due to the low speeds of associated diffusion. In addition, the substrate stability in the hot gases can be further considered by the use of a low temperature, low pressure flame, either with or without additional substrate cooling. YSZ and Pt have been deposited as powder, other materials can be deposited as a dust film with this technology. Thus, it should be emphasized that the present invention is broad in applicability and that the materials and substrates encompassed by the present invention are not limited to the materials listed above. With this in mind, examples that use the preferred embodiments of the methods and apparatuses described above are discussed below. Other features of the invention will become apparent from the following examples, which are for illustrative purposes only and are not intended as a food of the present invention.

P1082 / 98 X EXAMPLE I To illustrate the coating deposition capacity of the process of the present invention, simple oxide coatings were formed on a metal substrate. Si02 was deposited on a water-cooled aluminum foil from a solution of tetraethoxysilane [Si (0C2H5) 4] dissolved in isopropanol at 2.1% by weight of Si, additional isopropanol (3.2 ml) and propane (51 ml) were added. for a total silicon concentration of 0.06 M. The temperature of the gas for the deposit was 1190 ° C. The needle used to nebulize the precursor, as shown in Figure 3, was 304 stainless steel with OD = 0.012 inches and ID = 0.004 inches. The resistance over the length of the electrical flow of the needle was about 1.6 W. The small pilot flares formed from ethane and oxygen burned were used throughout the length of the deposit to maintain the flame. The solution was pumped to the needle at 3 ml / min and nebulized by controlling the amount of current through the needle. In this example, the current was 2.65 A. The pressure of the solution from pumping during a tank can vary from one run to another and is not important while maintaining a minimum pressure to ensure the proper properties of the fluid. In this case, the P108S / 98MX resulting pressure was 500 psi. Oxygen flowed around the solution, the flame was measured through the flow meter at a pressure of 30 psi at a flow rate of 4750 ml / min. The aluminum foil substrate was cooled during deposition in an air-water mist generated at 80 psi directed on the side of the substrate opposite the side on which the deposit occurred. The deposition rate for a coating applied at 1190 ° C for 48 seconds was approximately 1 μm / min and the deposition efficiency was 16.6% (calculated by dividing the weight gain by the available precursor material, total as reacted silica) . The amorphous coating was dense and adherent in the substrate. Although the surface of the coating was not as smooth as that achieved at deposit velocity in minors, new thin film interference colors were observed. The oxidation of the substrate did not occur.

EXAMPLE II In addition to coatings formed on metal substrates, such as the oxide deposited on aluminum of Example I, coatings have also been formed on plastic substrates. Platinum and a Teflon were deposited at a gas temperature of 200 to P1082 / 98MX 2600 ° C from a 0.005 M solution of platinum-acetylacetonate [Pt (CH3C0CHC0CH3) 2], toluene and methanol. The deposition apparatus used was similar to that used for Example I, except that two separate pilot lights were used and oxygen was supplied via the coaxial tube surrounding the reagent solution. The flow rate of the solution was 2 ml / min with a pressure of 1500 psi and a needle current of approximately 3.3A. The oxygen flowed at a pressure of 20 psi and a velocity of 4750 ml / min. The adherent film was smooth, dense and uniform. X-ray diffraction ("XRD") confirmed the formation of platinum with a preferred development direction (111). This example also illustrates that the coatings produced by the process of the present invention are not exactly oxide. Platinum was deposited with a pure element.

EXAMPLE III The coatings developed by the present invention are not limited in the formation on flat substrates. Films have been deposited on ceramic fiber tows used in the apparatus of the present invention. LaP04 was deposited on a tow of alumina fiber from the solution of triethylphosphate [CH2H5I) 3P04) dissolved in toluene at 1.7% by weight of P, des-ethylhexanoate P1082 / 98MX of lanthanum [La (00CCH (C2H5) C4H9) 3] dissolved in toluene at 1% La, additional toluene (16 ml) and propane (273 ml). The resulting solution had concentrations of P 0.0010 M and La 0.0013. The solution flowed at a rate of 3 ml / min at a pressure of 410 psi during deposition and was nebulized with a needle current of 2.36 A. The flow velocity of the oxygen to the solution flame was 4750 ml / min. a pressure of 30 psi. The 400 fibers in the tow were coated at the same time. Each fiber was approximately 12 mm in diameter. The tow moved slowly through the deposit area of the flame, twice. It only took two passes through the flame (where the tow was turned 180 degrees around its longitudinal axis for the second pass relative to the first pass) to produce a uniform coating on the individual fibers in the tow. The dense, columnar coatings produced at a gas temperature of 900 ° C varied from 300 to 500 mm in thickness for more than 50% fibers in the tow. There was no excessive degradation of the fibers from exposure to the flame. The XRD confirmed that the coating formed on the alumina fibers was monzanite, LaP04. This example also illustrates that the oxide coatings produced by the CCVD process are not limited to binary oxides. The LaP04 included P1082 / 98MX in this example was formed from a solution containing two precursors containing cations added to a ratio to obtain a film specific stoichiometry. The composition analysis of EDX showed that the atomic percentage of each cation deposited was as desired both at 900 and 1000 ° C.

EXAMPLE IV Example III illustrated the ability of the present invention to deposit coatings composed of more than one cation. Coatings from a solution with up to five different precursors that provide cations have also been deposited using an apparatus similar to that described in Example I. LaCr03 coatings were produced and purified with nickel, aluminum and strontium, from a solution containing lanthanum nitrate [La (N03) 3] dissolved in ethanol at 32.077% by weight La, chromium nitrate [Cr (N03) 3 ethanol nitrate at 13% Cr, strontium nitrate [Sr (N03) 2 ] dissolved in ethanol at 2% Sr, nickel nitrate [Ni (N03) 2] dissolved in ethanol at 2% Ni, aluminum nitrate [A1 (N03) 3] dissolved in 0.1% La ethanol, and ethanol (12 ml), isopropanol (25 ml) and water (5 ml). The resulting solution had concentrations of 0.045 M, Cr 0.040 M, Sr 0.005 M, Ni 0.005 M and Al 0.005 M. The solution P1082 / 98MX flowed at 2 ml / min at a pressure of 5200 psi, while oxygen flowed to the solution flame at a rate of 1600 ml / min and a pressure of 35 psi. The coatings were deposited at 1150 at 1250 ° C for 16 minutes on fused silica substrate. EDX analysis of a coating revealed the cation ratios of approximately 1: 26: 5: 5: 63 for AL, Cr, Ni, Sr and La, respectively, the successful deposition of the coating from precursors such as nitrates of low vapor pressure illustrates that the present invention is not limited to the deposit of organic metal reagents.

EXAMPLE V The ability to coat different substrates by the process of the present invention was illustrated in the previous examples. The stural relationships of the deposited film with a substrate have also been demonstrated using a similar process as described in Example I. PLZT (Pb, La, Zr, Ti) was deposited in MgO. (100) individual crystal from a solution containing Pb-2-ethylhexanoate [Pb (00CCH (C2H55) C4H9) 2] dissolved in toluene at 4% by weight of Pb, tris (2, 2, 6, -tetramethyl- 3, 5-heptanedioate) lanthanum [La (CH? 902) 3] dissolved in toluene a 0. 28% by weight of La, 2-ethylhexanoate Zr [Zr (00CCHC2H5) C4H9) 4] dissolved in toluene at 6% by weight of P1082 / 98 X Zr, (IV) i-propoxide Ti [OCH (CH3) 2] 4 dissolved in toluene at 0.82% by weight of Ti and all combined in toluene (95.8 ml). The resulting solution had concentrations of 0.0023 M, Zr, 0.0012 M, Pb 0.00120 M, and La 0.0003 M. The solution flowed at a rate of 1.5 ml / min with a pressure of 2400 psi during the deposit, while the oxygen flowed at a rate of 1600 ml / min and a pressure of 30 psi. An XRD pole figure pattern of value The maximum (101) for PLZT deposited in MgO at 700 ° C for 16 minutes showed a higher degree of epitaxy of the PLZT in the substrate. There were no intensities greater than 50 except in four locations of 44 degrees of Psi that were each at 90 ° Phi to each other. Different from 3 maximum values minors that were 0.005% of the maximum, there were no additional maximum values greater than 0.002% of the maximum. No additional epitaxial maximum values were present with the PLZT.

EXAMPLE VI Multilayer coatings have also been produced by the process of the invention using the apparatus described in Example I. The coating of twenty-two layers A15YSZ-16Y? Z was produced. alternating from two different solutions. He P1082 / 98MX YSZ was deposited from the solution of 0.51 g of 2-ethylhexanotate of Zr [Zr (OOCCH (C2H252) C4H9) 4] dissolved in toluene at 6% Zr and 0.80 g of 2-ethylhexanoate of Y [Y (OOCCH (C2H5) C4H9) 3] dissolved in toluene at 0.69% by weight and Y, all combined in 150 ml of toluene. The resulting concentrations were in Zr 0.0022 M and 6.004 M. The solution of YSZ-A1 consisted of the two precursors listed above at 0.38 g and 0.18 g, respectively, and 0.08 g of aluminum acetylacetonate [Al (CH3COCHCOCH3) 3] dissolved in toluene at 0.1% by weight of Al and combined in 150 ml of toluene. The coatings were produced from an individual flame, where the solution fed the flame was alternated every 3 minutes with a cleaning flow of toluene line between each solution for 1 minute. The flow velocity of the solution is kept constant at 3 ml / min for both solutions of the current through the needle which was consistently 3.3A. The pressure of the solution was 1700 to 200 psi. The oxygen fed to the flame flowed at a rate of 4750 ml / min and a pressure of 20 psi. The coating deposit took 90 minutes and was returned to a gas temperature of 1100 to 1150 ° C. The resulting multilayer coating was smooth, and dense 1 mm thick that no fissures were observed. The layer P1082 / 9TMX was approximately 40 nm thick.

EXAMPLE VII The CCVD process also allows the production of dust. The bound phase in which a powder can be created was demonstrated by the formation of YSZ powder in the first attempt to deposit the material as a powder. The solution used consisted of Zr 2-ethylhexanoate dissolved in toluene at 6% Y-2-ethylhexanoate dissolved in 0.69% toluene, toluene (6.9 ml) and propane (136.7 ml). The zirconium and yttrium concentrations were 0.005 M and 0.0003 M, respectively. The current through the needle during the deposit was 2.66 A. The temperature at which the powder deposit occurs was 700 ° C and the deposition time was 32 minutes. The powder was deposited on an aluminum sheet container that was filled with ice water. The water helped to cool the reservoir surface at a temperature much colder than that of the flame. The surface was sufficiently hot, although, there was no formation of excessive moisture condensation in the deposit area. Once the deposit was finished, some of the dust that was collected in the container was removed from the sheet and analyzed by electronic transport microcoscopy (TEM). The individual shaped powder grains was P1082 / 9TMTM differential of the large aggregates of the substance grains that result in the removal process. The EDX is used to confirm the presence of Zr and Y. The powder grain size varies from about 2 to 10 nm with most grains that are from 4 to 6 nm. In addition, the electron diffraction patterns obtained from the film were in the form of patterns, indicating that the powder was crystalline. The rings of the patterns were smooth and continuous as expected due to the small size of the grain. The d-shaped spacings of the material were calculated from the rings, and the values matched the expected d-spacings for YSZ. However, due to the limited number of rings available for indexing and the similarity between the values and the spacing of d for different types of zirconium with or without yttria, the specific structure (hexagonal, tetragonal, etc.) powder could not be determined from electronic diffraction. X-ray diffraction of the flat powder produced similar results, although a close match is made with a zirconia oxide stabilized with yttrium. It will be apparent to those skilled in the art that various modifications and variations may be made without departing from the scope or spirit of the invention. Other modalities will be apparent to those P1082 / 98MX skilled in the art from the consideration of the specification and practice of the invention described herein. It is proposed that the specification of the examples be considered as examples only, with the scope and true spirit of the invention indicated by the following claims.

P1082 / 98MX

Claims (56)

1. • CLAIMS 1. A method for coating a substrate with a selected material, comprising: a) at a first selected temperature and a first selected pressure, dissolving in a suitable carrier to thereby form a transport solution, one or more reagents able to react to form the selected material; b) placing a substrate in a region having a second selected pressure; c) pressurizing the transport solution to a third selected pressure up to the second selected pressure using a pressure regulating means; d) directing the transport solution, pressurized to a fluid conduit having an inlet end and an opposite outlet end, wherein the outlet end additionally comprises an outlet orifice oriented to direct the fluid in the conduit to the region and in the direction of the substrate; e) maintaining the solution at a second selected temperature from about 50 ° C below the critical temperature, Tc, of the solution to the T of the solution and keeping the third pressure selected above the second selected pressure and above the critical pressure or liquid phase, corresponding, Pc, P1082 / 98 X of the solution at the second temperature selected using the pressure regulating means; f) directing the pressurized solution through the outlet orifice of the conduit to the region to produce a spray of the nebulized solution in the direction of the substrate; g) mixing one or more selected gases in the spray of the nebulized solution to form a reactable spray; and h) exposing the reactable spray to a source of energy at a selected energization point, whereby the energy source provides sufficient energy to react the reactable spray, thereby forming the material and coating the substrate therewith. •2. A method for coating a substrate with a selected material, comprising: a) at a first selected temperature and a first selected pressure, dissolving in a suitable carrier to thereby form a transport solution, one or more reagents capable of reacting form the selected material; b) placing a substrate in a region having a second selected pressure; c) pressurize the transportation solution to a P1082 / 98MX third pressure selected up to the second selected pressure using a pressure regulating means; d) directing the transport solution, pressurized to a fluid conduit having an inlet end and an opposite outlet end, having a temperature regulating means placed therein to regulate the temperature of the solution at the end of the fluid. outlet, wherein the outlet end additionally comprises an outlet orifice oriented to direct the fluid in the conduit in the region and in the direction of the substrate, wherein the temperature regulating means comprises a means for resistively heating the conduit when applying to the same an electric current of a voltage selected from a source of electric current; e) heating the solution using the temperature regulating medium at a second selected temperature within 50 ° C above or below the critical temperature, Tc, of the solution, while maintaining the third selected pressure above the second pressure selected and above the critical pressure or liquid phase, corresponding, P, of the solution at the second selected temperature using the pressure regulating means; f) direct the heated, pressurized solution through the duct outlet in the region P1082 / 98MX to produce a spray of nebulized solution in the direction of the substrate; g) mixing one or more selected gases in the spray of the nebulized solution to form a reactable spray; and h) exposing the reactable spray to a source of energy at a selected energization point, whereby the energy source provides sufficient energy to react the reactable spray, thereby forming the material and coating the substrate therewith. 3. A method for coating a substrate with a selected material, comprising: a) at a first selected temperature and a first selected pressure, dissolving in a suitable carrier to thereby form a transport solution, one or more reagents capable of react to form the selected material; b) placing a substrate in a region having a second selected pressure; c) pressurizing the transport solution to a third selected pressure up to the second selected pressure using a pressure regulating means; d) directing the transport solution, pressurized to a fluid conduit having an inlet end and P1082 / 98 X an opposite outlet end having a temperature regulating means placed therein for regulating the temperature of the solution at the outlet end, wherein the outlet end further comprises an outlet orifice oriented to direct the fluid in the conduit to the region and in the direction of the substrate; e) heating the solution using the temperature regulating medium at a second selected temperature within 50 ° C above or below the critical temperature, Tc, of the solution, while keeping the third pressure selected above the second pressure selected and above the critical pressure or liquid phase, corresponding, Pc, of the solution at the second selected temperature, using the pressure regulating means; f) directing the heated, pressurized solution through the exit orifice of the conduit in the region to produce a spray of the nezed solution in the direction of the substrate; g) mixing one or more selected gases in the spray of the nezed solution to form a reactable spray; and h) exposing the reactable spray to a source of energy at a selected energization point, whereby the energy source provides sufficient P1082 / 98MX energy to react the reactable spray, thereby forming the material and coating the substrate with it, wherein the energy source comprises a flame source and the selected energization point comprises an ignition point and where the reactable spray comprises a fuel spray having a fuel spray speed and wherein the fuel spray rate is greater than the flame rate of the flame source at the ignition point and further comprising one or more assisting means to ignition to ignite the fuel spray. The method according to claim 1 or 2, wherein the energy source comprises a flame source and the selected energization point comprises an ignition point. The method according to claim 1 or 2, wherein the energy source comprises a plasma torch. The method according to claim 1, 2, or 3, wherein the second pressure selected from the region is the ambient pressure. The method according to claim 1, 2, or 3, wherein the second pressure selected from the region is reduced to produce a combustion flame having a temperature of less than 1000 ° C. P1082 / 98MX 8. The method according to claim 1, 2, or 3, wherein the carrier is propane and the transport solution comprises at least 50% by volume of propane. The method according to claim 8, wherein the transport solution further comprises butanol, ethanol, isopropanol, toluene or a combination thereof. The method according to claim 1, 2, or 3, further comprising, during step c), a pressurized container, which brings a normal pressure and temperature gas into contact with the transport solution at a selected pressure sufficient to form a liquid or supercritical fluid. The method according to claim 10, wherein the concentration of the reagent of the transport solution is between 0.0005 M and 0.05 M. 12. The method according to claim 1, 2, or 3, wherein the outlet end of the conduit it further comprises a fluid introduction orifice and further comprising before the direction of the heated solution, pressurized through the outlet orifice of the conduit, adding the fluid to the heated solution, pressurized through the fluid introduction orifice to form in this way a combined solution having a reduced critical temperature. P1082 / 98MX 13. The method according to claim 1, 2, or 3, wherein each of one or more reagents has a vapor pressure of not less than about 25% gives the vapor pressure of the carrier. 14. The method according to claim 1, 2, or 3, wherein the outlet end of the conduit comprises tubing having an internal diameter of 25 to 125 μm. The method according to claim, wherein the temperature regulating means comprises means for resistively heating the conduit by applying thereto an electric current of a selected voltage from an electric current source. 16. The method according to claim 2 or 15, wherein the means for resistively heating the conduit comprises a contact placed in the space of 4 mm from the outlet orifice. The method according to claim 1, 2, or 3, wherein the carrier and one or more reagents are selected such that the second temperature selected is the ambient temperature. The method according to claim 1, 2, or 3, wherein the material coating the substrate comprises a metal, a metal oxide, a carbonate, a sulfate, a phosphate, a nitride, carbide, boride, metal, a material that does not contain oxygen, at least 90% silica, or a P1082 / 98MX combination thereof. The method of claim 4, wherein the reactable spray comprises a fuel spray having a fuel spray speed and wherein the fuel spray rate is greater than the flame rate of the flame source in the fuel. point of ignition and further comprises one or more ignition aid means for igniting the fuel spray. The method according to claim 19, wherein the fuel spraying speed is greater than a mach. The method according to claim 1, 2, or 3, further comprising, during the exposure step, cooling the substrate using a substrate cooling medium. The method according to claim 1, 2, or 3, wherein the material coating the substrate comprises a carbon material, diamond, or (1) diamond and (2) a metal oxide, a metal carbide or a metal. 23. The method according to claim 1, 2, or 3, wherein the material coating the substrate comprises a graduated composition. 24. The method according to claim 1, 2, or 3, wherein the material coating the substrate comprises a P1082 / 98MX amorphous material. 25. The method according to claim 1, 2, or 3, further comprising flowing a wrapping gas, selected around the reactable spray, thereby decreasing entrained impurities and maintaining a favorable deposit environment. 26. The method according to claim 1, 2, or 3, wherein the second pressure selected is about 20 torr. 27. An apparatus for coating a substrate with a selected material, comprising: a) a pressure regulating means for pressurizing a transport solution into a transport solution tank at a first selected pressure, wherein the transport solution comprises a suitable carrier having dissolved therein one or more reactants capable of reacting to form the selected material and wherein the means for pressurizing is capable of maintaining a first selected pressure above the critical pressure or corresponding liquid phase, Pc, from the transport solution to the temperature of the transport solution; b) a fluid conduit having an inlet end in fluid connection with the transport solution reservoir and an opposite outlet end that P1082 / 98 X has an outlet orifice oriented to direct the fluid in the conduit to a region of a second selected pressure below the first selected pressure and in the substrate orientation, wherein the outlet orifice additionally comprises a means for nebulizing a solution to form a spray of nebulized solution; c) a gas supply means for mixing one or more gases in the spray of nebulized solution to form a reactable spray; and d) a source of energy at a selected energizing point to react the reactable spray, whereby the energy source provides sufficient energy to react the reactable spray of region of the selected second pressure, thereby coating the substrate. 28. An apparatus for coating a substrate with a selected material, comprising: a) a pressure regulating means for pressurizing a transport solution into a transport solution tank at a first selected pressure, wherein the transport solution comprises a suitable carrier that has dissolved in it one or more reagents capable of reacting to form the selected material P1082 / 98MX and wherein the means for pressurizing is capable of maintaining a first selected pressure above the critical pressure or corresponding liquid phase, Pc, of the transport solution at the temperature of the transport solution; b) a fluid conduit having an inlet end in fluid connection with the transport solution reservoir and an opposite outlet end having an outlet orifice oriented to direct the fluid in the conduit to a region of a second pressure selected below the first selected pressure and in the substrate orientation, wherein the outlet orifice additionally comprises a means for nebulizing a solution to form a spray of nebulized solution; c) a temperature regulation means placed in thermal connection with the outlet end of the fluid conduit to regulate the temperature of the solution at the outlet end within 50 ° C above or below the critical temperature, tc, of the solution, wherein the temperature regulating means comprises means for resistively heating the conduit by applying thereto an electric current of a selected voltage from an electric current source; d) a gas supply means for mixing one P10B2 / 98MX or more gases in the nebulized solution spray to form a reactable spray; and e) a power source at a selected energization point to be reactable reactable spray, whereby the energy source provides sufficient energy to react the region reactable spray of the selected second pressure, thereby coating the substrate. 29. An apparatus for coating a substrate with a selected material, comprising: a) a pressure regulating means for pressurizing a transport solution into a transport solution tank at a first selected pressure, wherein the transport solution comprises a suitable carrier having dissolved therein one or more reactants capable of reacting to form the selected material and wherein the means for pressurizing is capable of maintaining a first selected pressure above the critical pressure or corresponding liquid phase, Pc, from the transport solution to the temperature of the transport solution; b) a fluid conduit having an inlet end in fluid connection with the transport solution reservoir and an opposite outlet end that P1082 / 98MX has an outlet orifice oriented to direct the fluid in the conduit to a region of a selected second pressure below the first selected pressure and in the substrate orientation, wherein the outlet orifice additionally comprises a means for nebulising a solution for forming a spray of nebulized solution; c) a temperature regulating means placed in thermal connection with the outlet end of the fluid conduit to regulate a temperature of the solution at the outlet end within 50 ° C above or below the critical temperature, Tc, of the solution; d) a gas supply means for mixing one or more gases in the spray of nebulized solution to form a reactable spray; and e) a source of energy at a selected energization point to be reactable reactable spray, whereby the energy source provides sufficient energy to react the reactable spray of region of the selected second pressure, thereby coating the substrate, wherein the energy source comprises a flame source and the selected energization point comprises an ignition point and wherein the reactable spray comprises a fuel spray "which P1082 / 98MX has a fuel spray speed and wherein the fuel spray speed is greater than the flame rate of the flame source at the ignition point and further comprises one or more ignition aids to ignite the spray made out of fuel. The apparatus according to claim 27 or 28, wherein the energy source comprises a flame source and the selected energization point comprises an ignition point. 31. The apparatus according to claim 27 or 28, wherein the energy source comprises a plasma torch. 32. The apparatus according to claim 27, 28, or 29, wherein the second pressure selected from the region is the ambient pressure. 33. The apparatus according to claim 27, 28, or 29, wherein the second pressure selected from the region is reduced to produce a combustion flame having a temperature of less than 1000 ° C. 34. The apparatus according to claim 27, 28, or 29, wherein the outlet end of the conduit further comprises a fluid introduction port. 35. The apparatus according to claim 27, 28, or 29, wherein the outlet end of the conduit comprises P1082 / 98MX pipe having an internal diameter of 10 to 250 μm. 36. The apparatus according to claim 29, wherein the temperature regulating means comprises means for resistively heating the conduit by applying thereto an electric current of a selected voltage from an electric current source. 37. The apparatus according to claim 28 or 36, wherein the means for resistively heating the conduit comprises a contact placed within the 4 mm space of the outlet orifice. 38. The apparatus according to claim 27 or 28, wherein the reactable spray comprises a fuel spray having a fuel spray speed and wherein the fuel spray rate is greater than the flame rate of the flame source. at the point of ignition and further comprising one or more ignition aids to ignite the fuel spray. 39. The apparatus according to claim 38, wherein the fuel spraying speed is greater than a mach. 40. The apparatus according to claim 27, 28, or 29, further comprising a substrate cooling means for cooling the substrate. 41. The apparatus according to claim 27, 28, or P1-082 / 98MX 29, further comprising means for flowing a selected jacket gas around the reactable spray thereby decreasing entrained impurities and maintaining a favorable deposition environment. 42. The apparatus according to claim 27, 28, or 29, wherein the second selected portion is above 20 torr. 43. A method for creating a powder material in a region, comprising: a) at a first selected temperature and a first selected pressure, dissolving in a suitable carrier to thereby form a transport solution, one or more reagents capable of reacting to form the powder material in the region, wherein the region has a second selected pressure lower than the first selected pressure; b) pressurizing the transport solution to a selected third pressure above the second selected pressure using a pressure regulating means; c) directing the transport solution, pressurized to a fluid conduit having an inlet conduit and an opposite outlet end having a temperature regulating means placed therein to regulate the P1082 / 98MX temperature of the solution at the outlet end, where the outlet end further comprises an outlet orifice oriented to direct the fluid in the conduit to the region. d) heating the solution using the temperature regulating medium at a second selected temperature from about 50 ° C above the critical temperature, Tc, of the solution to the Tc, of the solution while maintaining the third pressure selected above of the second pressure selected and above the critical pressure or corresponding liquid phase, Pc, of the solution at the second selected temperature using the pressure regulating means; e) directing the heated, pressurized solution through the exit orifice of the conduit in the region to produce a spray of nebulized solution; f) mixing one or more selected gases in the nebulized solution spray to form a reactable spray; and g) exposing the reactable spray to a power source at a selected energization point, whereby the energy source provides sufficient energy to react the reactable spray, thereby forming the material in the region. P1082 / 98MX 44. A method for creating a powder material in a region, comprising: a) at a first temperature, selected and a first pressure selected, dissolved in a suitable carrier to thereby form a transport solution, one or more reagents capable of reacting to form the powder material in the region, wherein the region has a second selected pressure lower than the first selected pressure; b) pressurizing the transport solution to a selected third pressure above the second selected pressure using a pressure regulating means; c) directing the transport solution, pressurized to a fluid conduit having an inlet conduit and an opposite outlet end having a temperature regulating means positioned thereon to regulate the temperature of the solution at the outlet end, wherein the outlet end further comprises an outlet orifice oriented to direct the fluid in the conduit to the region, wherein the temperature regulating means comprises a means for resistively heating the conduit by applying an electric current of a selected voltage thereto. from a source of electric current. d) heating the solution using the regulating medium P1082 / 98MX of temperature at a second selected temperature from about 50 ° C above or below the critical temperature, Tc, of the solution while maintaining the selected third pressure above the second pressure selected and above the Critical or liquid phase pressure, corresponding, Pc, 'of the solution at the second selected temperature using the pressure regulating means; e) directing the heated, pressurized solution through the exit orifice of the conduit in the region to produce a spray of nebulized solution; f) mixing one or more selected gases in the nebulized solution spray to form a reactable spray; and g) exposing the reactable spray to an energy source at a selected energization point, whereby the energy source provides sufficient energy to react the reactable spray, thereby forming the material in the region. 45. A method for creating a powder material in a region comprising: a) at a first temperature, selected and a first selected pressure, dissolved in a suitable carrier to thereby form a solution of P1082 / 98MX transport, one or more reagents capable of reacting to form the powder material in the region, wherein the region has a second selected pressure lower than the first selected pressure; b) pressurizing the transport solution to a selected third pressure above the second selected pressure using a pressure regulating means; c) directing the transport solution, pressurized to a fluid conduit having an inlet conduit and an opposite outlet end having a temperature regulating means positioned thereon to regulate the temperature of the solution at the outlet end, wherein the outlet end further comprises an outlet orifice oriented to direct the fluid in the conduit to the region. d) heating the solution using the temperature regulating medium at a second selected temperature from about 50 ° C above or below the critical temperature, Tc, of the solution while maintaining the third selected pressure above the second pressure selected and above the critical pressure or liquid phase, corresponding, Pc, of the solution at the second selected temperature using the pressure regulating means; P1082 / 98MX e) directing the heated, pressurized solution through the exit orifice of the conduit in the region to produce a spray of nebulized solution; f) mixing one or more selected gases in the nebulized solution spray to form a reactable spray; and g) exposing the reactable spray to a source of energy at a selected energization point, whereby the energy source provides sufficient energy to react the reactable spray, thereby forming the material in the region, where the source of energy comprises a flame source and the selected energization point comprises an ignition point and wherein the reactable spray comprises a fuel spray having a fuel spray speed and wherein the fuel spray rate is greater than the speed Flame of the flame source at the ignition point and further comprising one or more ignition aids to ignite the fuel spray. 46. The method according to claim 43, 44 or 45, further comprising mixing a selected substrate material with the transport solution. 47. The method according to claim 43, 44 or P1082 / 98MX 45, wherein the concentration of the transport solution is between 0.005 M and 5 M. 48. An apparatus for creating a powder material, comprising: a) a pressure regulating means for pressurizing to a selected first pressure a transport solution in a transport solution tank, wherein the transport solution comprises a suitable carrier having dissolved therein one or more reagents capable of reacting to form the selected material and wherein the means for pressurizing is capable of maintaining a first selected pressure above the critical pressure or liquid phase, corresponding, Pc / of the transport solution at the temperature of the transport solution; b) a fluid conduit having an inlet end in fluid connection with the transport solution reservoir and an opposite outlet end having an outlet orifice oriented to direct the fluid in the conduit to a region of a second pressure selected below the first pressure selected and in the substrate orientation, wherein the outlet orifice additionally comprises a means for nebulizing a solution to form a spray of nebulized solution; P1082 / 98MX c) a temperature regulating means placed at the outlet end of the fluid conduit to regulate the temperature of the solution at the outlet end; d) a gas supply means for mixing one or more gases in the spray of nebulized solution to form a reactable spray; and e) a power source at a selected energization point to be reactable reactable spray, whereby the energy source provides sufficient energy to react the region reactable spray of the selected second pressure, thereby coating the substrate. 49. An apparatus for creating a powder material, comprising: a) a pressure regulating means for pressurizing a transport solution in a transport solution tank at a first selected pressure, wherein the transport solution comprises a suitable carrier having dissolved therein one or more reactants capable of reacting to form the selected material and wherein the means for pressurizing is capable of maintaining a first selected pressure above the critical pressure or corresponding liquid phase, Pc, of the transport solution at the temperature of the solution P1082 / 9TMX transport; b) a fluid conduit having an inlet end in fluid connection with the transport solution reservoir and an opposite outlet end having an outlet orifice oriented to direct the fluid in the conduit to a region of a second pressure selected below the first pressure selected and in the substrate orientation, wherein the outlet orifice additionally comprises a means for nebulizing a solution to form a spray of nebulized solution; c) a temperature regulating means positioned at the outlet end of the fluid conduit for regulating the temperature of the solution at the outlet end, wherein the temperature regulating means comprises a means for resistively heating the conduit by applying thereto a electric current of a selected voltage from an electric current source; d) a gas supply means for mixing one or more gases in the spray of nebulized solution to form a reactable spray; and e) a source of energy at a selected energization point to be reactable reactant spray, whereby the energy source provides sufficient energy to make P1082 / 98MX react reactable spray region of the second selected pressure, thereby forming the powder material. 50. An apparatus for creating a powder material, comprising: a) a pressure regulating means for pressurizing a transport solution into a transport solution tank at a first selected pressure, wherein the transport solution comprises a suitable carrier having dissolved therein one or more reactants capable of reacting to form the selected material and wherein the means for pressurizing is capable of maintaining a first selected pressure above the critical pressure or corresponding liquid phase, Pc, of the transport solution at the temperature of the transport solution; b) a fluid conduit having an inlet end in fluid connection with the transport solution reservoir and an opposite outlet end having an outlet orifice oriented to direct the fluid in the conduit to a region of a second pressure selected below the first pressure selected and in the substrate orientation, wherein the outlet orifice additionally comprises a means for nebulizing a solution to form a spray. P1082 / 98MX nebulized solution; c) a temperature regulating means positioned at the outlet end of the fluid conduit to regulate the temperature of the solution at the outlet end; d) a gas supply means for mixing one or more gases in the spray of nebulized solution to form a reactable spray; and e) a source of energy at a selected energizing point to be reactable reactant, whereby the energy source provides sufficient energy to react the reactable atom of region of the selected second pressure, thereby forming the material in powder, wherein the energy source comprises a flame source and the selected energization point comprises an ignition point and wherein the reactable spray comprises a fuel spray having a fuel spray speed and wherein the spray rate of fuel is greater than the flame rate of the flame source at the point of ignition and further comprises one or more ignition assist means for igniting the fuel spray. 51. A coating on a substrate produced by the process of claim 1, 2 or 3. P1082 / 98MX 52. A powder produced by the process of claim 43, 44 or 45. The method according to claim 1, wherein the outlet end of the fluid conduit further comprises a temperature regulating means positioned thereon to regulate the temperature of the fluid. the solution at the exit end. 54. The method according to claim 53, wherein the temperature regulating means comprises a means for resistively heating the conduit by applying thereto an electric current of a selected voltage from an electric current source. 55. The apparatus according to claim 27, wherein the outlet end of the fluid conduit further comprises a temperature regulating means positioned thereon for regulating the temperature of the solution at the outlet end from about 50 ° C below the outlet. the critical temperature, Tc, of the solution to the Tc of the solution. 56. The apparatus according to claim 55, wherein the temperature regulating means comprises means for resistively heating the conduit by applying thereto an electric current of a selected voltage from an electric current source. P1082 / 98MX