WO2013026177A1

WO2013026177A1 - Phosphorous-comprising dopants, methods for forming phosphorous-doped regions in semiconductor substrates using such phosphorous-comprising dopants, and methods for forming such phosphorous-comprising dopants

Info

Publication number: WO2013026177A1
Application number: PCT/CN2011/001392
Authority: WO
Inventors: Hongmin Huang; Carol Gao; Zhe Ding; Albert Peng; Ya Qun Liu; Bright ZHANG
Original assignee: Honeywell International Inc.
Priority date: 2011-08-22
Filing date: 2011-08-22
Publication date: 2013-02-28
Also published as: TW201314746A; TWI608525B

Abstract

Substantially silane-free phosphorous-comprising dopants, methods for forming phosphorous-doped regions in a semiconductor material using substantially silane-free phosphorous-comprising dopants, and a method for fabricating substantially silane-free phosphorous-comprising dopants are provided. A phosphorous-comprising dopant comprises a phosphorous source comprising a phosphorous-comprising salt, a phosphorous-comprising acid, phosphorous-comprising anions, or combinations thereof, an alkaline material, cations from an alkaline material, or combinations thereof, and a liquid medium. The phosphorous-comprising dopant comprises less than 0.1wt.% silanes, oligomers and/or polymers derived from silanes, or a combination thereof.

Description

PHOSPHOROUS-COMPRISING DOPANTS, METHODS FOR FORMING PHOSPHOROUS-DOPED REGIONS IN SEMICONDUCTOR SUBSTRATES USING SUCH PHOSPHOROUS-COMPRISING DOPANTS, AND METHODS FOR FORMING

SUCH PHOSPHOROUS-COMPRISING DOPANTS

CROSS-REFERENCES TO RELATED APPLICATIONS

This is a continuation-in-part of Application No. 12/194,688, filed August 20,

TECHNICAL FIELD

[0002] The present invention generally relates to dopants, methods for doping regions of semiconductor-comprising materials, and methods for forming dopants, and more particularly relates to substantially silane-free phosphorous-comprising dopants, thixotropic phosphorous-comprising dopants, methods for forming phosphorous-doped regions in semiconductor materials using such phosphorous-comprising dopants, and methods for forming such phosphorous-comprising dopants.

BACKGROUND

[0003] Doping of semiconductor materials with conductivity-determining type impurities, such as n-type and p-type elements, is used in a variety of applications that require modification of the electrical characteristics of the semiconductor materials. Photolithography is a well-known method for performing such doping of semiconductor materials. To dope a semiconductor material, photolithography requires the use of a mask that is formed and patterned on the semiconductor materials. Ion implantation is performed to implant conductivity-determining type ions into the semiconductor materials. A high- temperature anneal then is performed to cause the impurity dopants to diffuse into the semiconductor materials.

[0004] In some applications, such as, for example, solar cells, it is desirable to dope the semiconductor materials in a pattern having very fine lines or features. The most common type of solar cell is configured as a large-area p-n junction made from silicon. In one type of such solar cell 10. illustrated in FIG. 1, a silicon wafer 12 having a light-receiving front side 14 and a back side 16 is provided with a basic doping, wherein the basic doping can be of the n-type or of the p-type. The silicon wafer is further doped at one side (in FIG. 1, front side 14) with a dopant of opposite charge of the basic doping, thus forming a p-n junction 18 within the silicon wafer. Photons from light are absorbed by the light-receiving side 14 of the silicon wafer to the p-n junction where charge carriers, i.e., electrons and holes, are separated and conducted to a conductive contact, thus generating electricity. The solar cell is usually provided with metallic contacts 20, 22 on the light-receiving front side as well as on the back side, respectively, to carry away the electric current produced by the solar cell. The metal contacts on the light-receiving front side pose a challenge in regard to the degree of efficiency of the solar cell because the metal covering of the front side surface causes shading of the effective area of the solar cell. Although it may be desirable to reduce the metal contacts as much as possible to reduce the shading, a metal covering of approximately 10% remains unavoidable since the metallization has to occur in a manner that keeps the electrical losses small. In addition, contact resistance within the silicon adjacent to the electrical contact increases significantly as the size of the metal contact decreases. However, a reduction of the contact resistance is possible by doping the silicon in narrow areas 24 directly adjacent to the metal contacts on the light-receiving front side 14.

[0005] FIG. 2 illustrates another common type of solar cell 30. Solar cell 30 also has a silicon wafer 12 having a light-receiving front side 14 and a back side 16 and is provided with a basic doping, wherein the basic doping can be of the n-type or of the p-type. The light-receiving front side 14 has a rough or textured surface that serves as a light trap, preventing absorbed light from being reflected back out of the solar cell. The metal contacts 32 of the solar cell are formed on the back side 16 of the wafer. The silicon wafer is doped at the backside relative to the metal contacts, thus forming p-n junctions 18 within the silicon wafer. Solar cell 30 has an advantage over solar cell 10 in that all of the metal contacts of the cell are on the back side 16. In this regard, there is no shading of the effective area of the solar cell. However, for all contacts to be formed on the back side 16, the doped regions adjacent to the contacts have to be quite narrow.

[0006] Phosphorous is commonly used to form n-type regions in semiconductor materials. Both solar cell 10 and solar cell 30 benefit from the use of very fine, narrow phosphorous- doped regions formed within a semiconductor substrate. However, the present-day method of doping described above, that is, photolithography, presents significant drawbacks. For example, while doping of substrates in fine-lined patterns is possible with photolithography, DhotolithoeraDhv is an expensive and time consuming process. [0007] Other well-known methods for performing doping of semiconductor materials, such as screen printing, roller printing, spray application, and spin application, use a liquid dopant that is applied to the semiconductor materials. While such methods can overcome the shortcomings of photolithography, the dopants commonly are formed by hydrolysis and polymerization in a sol-gel process using silanes. Use of silanes in a sol-gel process has a number of drawbacks. For example, the molecular weight of the resulting dopant tends to continue to increase with time. The increasing molecular weight of the dopant causes gelling of the dopant. Thus, the dopant is unstable and must be transferred and stored at low temperatures. Further, if gelling occurs during use, it can cause clogging of screens during screen printing. In addition, the sol-gel process typically requires a solvent or solvent system that can be unsafe during manufacture and environmentally unfriendly. It also is difficult to control line widths of such dopants, particularly when fine features are being printed. During dopant diffusion or "dopant drive-in," "out-diffusion" often occurs. "Out- diffusion" is vaporization of the dopant that resettles on the semiconductor material, resulting in doping of unprinted areas of the semiconductor material during diffusion.

[0008] Accordingly, it is desirable to provide phosphorous-comprising dopants that can be used in doping processes that result in fine-featured patterns. It is also desirable to provide phosphorous-comprising dopants that do not comprise silanes. In addition, it is desirable to provide methods for forming phosphorous-comprising dopants that comprise substantially no silanes and that can be used in doping processes that are time and cost efficient. Furthermore, other desirable features and characteristics of the present invention will become apparent from the subsequent detailed description of the invention and the appended claims, taken in conjunction with the accompanying drawings and this background of the invention.

BRIEF SUMMARY

[0009] Phosphorous-comprising dopants, methods for forming phosphorous-doped regions in a semiconductor material, and methods for fabricating phosphorous-comprising dopants are provided. In accordance with an exemplary embodiment, a phosphorous- comprising dopant comprises a phosphorous source comprising a phosphorous-comprising salt, a phosphorous-comprising acid, phosphorous-comprising anions, or combinations thereof, an alkaline material, cations from an alkaline material, or combinations thereof, and a liquid medium. The phosphorous-comprising dopant comprises less than 0.1 wt. % silanes, oligomers and/or polymers derived from silanes, or a combination thereof.

[0010] In accordance with another exemplary embodiment, a method for forming phosphorous-doped regions in a semiconductor material comprises providing a phosphorous-comprising dopant formed using a phosphorous-comprising acid, a phosphorous-comprising salt, or combinations thereof and an alkaline material, cations from an alkaline material, or combinations thereof, in a liquid medium. The phosphorous- comprising dopant comprises less than 0.1 wt. % silanes, oligomers and/or polymers derived from silanes, or a combination thereof. The phosphorous-comprising dopant is deposited overlying at least a portion of the semiconductor material. The liquid medium of the phosphorous-comprising dopant is caused to evaporate and phosphorous elements derived from the phosphorous-comprising dopant are diffused into the semiconductor material.

[0011] In accordance with a further exemplary embodiment, a method of forming a phosphorous-comprising dopant comprises providing a phosphorous source comprising a phosphorous-comprising acid or phosphorous-comprising salt, or combinations thereof, and combining the phosphorous source with an alkaline material and a liquid medium. The phosphorous-comprising dopant comprises less than 0.1 wt. % silanes, oligomers and/or polymers derived from silanes, or a combination thereof.

[0012] In yet another embodiment, a phosphorous-comprising dopant comprises a phosphorous source comprising a phosphorous-comprising salt, a phosphorous-comprising acid, phosphorous-comprising anions, or combinations thereof, an alkaline material, cations from an alkaline material, or combinations thereof, a liquid medium, and treated silica particles.

[0013] In accordance with a further embodiment, a phosphorous-comprising dopant comprises a phosphorous source comprising a phosphorous-comprising salt, a phosphorous- comprising acid, phosphorous-comprising anions, or combinations thereof, a hydrocarbon group-comprising alkaline material, cations from a hydrocarbon group-comprising alkaline material, or combinations thereof, and a liquid medium.

BRIEF DESCRIPTION OF THE DRAWINGS

[0014] The present invention will hereinafter be described in conjunction with the following drawing figures, wherein like numerals denote like elements, and wherein: [0015] FIG. 1 is a schematic illustration of a conventional solar cell with a light-side contact and a back side contact;

[0016] FIG. 2 is a schematic illustration of another conventional solar cell with back side contacts;

[0017] FIG. 3 is a cross-sectional view of an inkjet printer mechanism distributing ink on a substrate;

[0018] FIG. 4 is a cross-sectional view of an aerosol jet printer mechanism distributing ink on a substrate;

[0019] FIG. 5 is a flowchart of a method for forming phosphorous-doped regions in a semiconductor material using a non-contact printing process in accordance with an exemplary embodiment of the present invention;

[0020] FIG. 6 is a flowchart of a method for fabricating a phosphorous-comprising dopant for use in the method of FIG. 5 in accordance with an exemplary embodiment of the present invention; and

[0021] FIG. 7 is a flowchart of a method for fabricating a phosphorous-comprising dopant for use in the method of FIG. 5 in accordance with another exemplary embodiment of the present invention.

DETAILED DESCRIPTION

[0022] The following detailed description of the invention is merely exemplary in nature and is not intended to limit the invention or the application and uses of the invention. Furthermore, there is no intention to be bound by any theory presented in the preceding background of the invention or the following detailed description of the invention.

[0023] Phosphorous-comprising dopants for forming phosphorous-doped regions in semiconductor materials, methods for fabricating such phosphorous-comprising dopants, and methods for forming phosphorous-doped regions in semiconductor material using such phosphorous-comprising dopants are provided herein. The phosphorous-doped regions are formed using a "doping process." As used herein, the term "doping process" includes deposition and diffusion, where deposition includes both "non-contact printing processes" and contact printing processes.

[0024] Examples of non-contact printing processes include but are not limited to "inkjet printing" and "aerosol jet printing." Typically, the terms "inkjet printing," an "inkjet nrintine orocess." "aerosol iet orintine." and an "aerosol iet printing process" refer to a non- contact printing process whereby a fluid is projected from a nozzle directly onto a substrate to form a desired pattern. In an inkjet printing mechanism 50 of an inkjet printer, as illustrated in FIG. 3, a print head 52 has several tiny nozzles 54, also called jets. As a substrate 58 moves past the print head 52, or as the print head 52 moves past the substrate, the nozzles spray or "jet" ink 56 onto the substrate in tiny drops, forming images of a desired pattern. An aerosol jet printing mechanism 60, illustrated in FIG. 4, uses a mist generator or nebulizer 62 that atomizes a fluid 64. The atomized fluid 66 is aerodynamical ly focused using a flow guidance deposition head 68, which creates an annular flow of sheath gas, indicated by arrow 72, to collimate the atomized fluid 66. The co-axial flow exits the flow guidance head 68 through a nozzle 70 directed at the substrate 74, which serves to focus a stream 76 of the atomized material to as small as a tenth of the size of the nozzle orifice (typically ΙΟΟμιη). Patterning is accomplished by attaching the substrate to a computer-controlled platen, or by translating the flow guidance head while the substrate position remains fixed.

[0025] Such non-contact printing processes are particularly attractive processes for fabricating doped regions in semiconductor materials for a variety of reasons. First, only a dopant that is used to form the doped regions touches or contacts the surface of the substrate upon which the dopant is applied. Thus, because the breaking of semiconductor substrates could be minimized compared to other known processes, non-contact processes are suitable for a variety of substrates, including rigid and flexible substrates. In addition, such non- contact processes are additive processes, meaning that the dopant is applied to the substrate in the desired pattern. Thus, steps for removing material after the printing process, such as is required in photolithography, are eliminated. Further, because such non-contact processes are additive processes, they are suitable for substrates having smooth, rough, or textured surfaces. Non-contact processes also permit the formation of very fine features on semiconductor materials. In one embodiment, features, such as, for example, lines, dots, rectangles, circles, or other geometric shapes, having at least one dimension of less than about 200 microns (μηι) can be formed. In another exemplary embodiment, features having at least one dimension of less than about 100 μη can be formed. In a preferred embodiment, features having at least one dimension of less than about 20 μηι can be formed. In addition, because non-contact processes involve digital computer printers that can be programmed with a selected pattern to be formed on a substrate or that can be provided the pattern from a host computer, no new masks or screens need to be produced when a change in the pattern is desired. All of the above reasons make non-contact printing processes cost-efficient processes for fabricating doped regions in semiconductor materials, allowing for increased throughput compared to photolithography.

[0026] However, while non-contact printing processes may be used for forming doped regions in a semiconductor material in accordance with certain exemplary embodiments of the methods contemplated herein, the invention is not so limited and, in other exemplary embodiments, the phosphorous-comprising dopants can be deposited using other application processes such as screen printing, spray application, spin application, and roller application. Screen printing involves the use of a patterned screen or stencil that is disposed over a semiconductor material. Liquid dopant is placed on top of the screen and is forced through the screen to deposit on the semiconductor material in a pattern that corresponds to the pattern of the screen. Spin application involves spinning the semiconductor material at a high spin speed such as, for example, up to 1200 revolutions per minute or even higher, while spraying the liquid dopant onto the spinning semiconductor material at a desired fluid pressure. Spinning causes the liquid dopant to spread outward substantially evenly across the semiconductor material. The liquid dopant also can be sprayed onto an unmoving semiconductor material at a desired fluid pressure at a position substantially at the center of the semiconductor material. The fluid pressure causes the dopant to spread radially and substantially evenly across the wafer. Roller printing involves a roller upon which is engraved a pattern. The liquid dopant is applied to the engraved pattern of the roller, which is pressed against a semiconductor material and rolled across the semiconductor material, thereby transferring the liquid dopant to the semiconductor material according to the pattern on the roller.

[0027] Referring to FIG. 5, in accordance with an exemplary embodiment, a method 100 for forming a phosphorous-doped region in a semiconductor material includes the step of providing a semiconductor material (step 102). As used herein, the term "semiconductor material" will be used to encompass semiconductor materials conventionally used in the semiconductor industry from which to make electrical devices. Semiconductor materials include monocrystalline silicon materials, such as the relatively pure or lightly impurity- doped monocrystalline silicon materials typically used in the semiconductor industry, as well as polycrystalline silicon materials, and silicon admixed with other elements such as germanium, carbon, and the like. In addition, "semiconductor material" encompasses other materials such as relatively pure and impurity-doped germanium, gallium arsenide, zinc oxide, glass, and the like. In this regard, the method 100 can be used to fabricate a variety semiconductor devices including, but not limited to. microelectronics, solar cells, displays, RFID components, microelectromechanical systems (MEMS) devices, optical devices such as microlenses, medical devices, and the like.

[0028] In an optional embodiment, the semiconductor material is subjected to a pre- dopant treatment (step 1 12). A pre-dopant treatment is any treatment that facilitates adhesion and performance of a formed pattern of a subsequently-applied dopant, described in more detail below, to the semiconductor material or that facilitates diffusion of the phosphorous elements of the subsequently-applied dopant into the semiconductor material. For example, pre-dopant treatments include cleaning of the semiconductor material to remove particles, native oxides, organic or inorganic contamination, or the like from the semiconductor material, or treating the semiconductor material so that it becomes more hydrophilic or hydrophobic. Examples of pre-dopant treatment includes applying to the semiconductor material acids, such as hydrofluoric acid (HF), hydrochloric acid (HC1), sulfuric acid (H₂S0₄), and/or nitric acid (HN0₃), bases, such as ammonium hydroxide (NH₄OH), sodium hydroxide (NaOH), potassium hydroxide (KOH), and tetramethylammonium hydroxide (TMAH), oxidizers, such as hydrogen peroxide (H₂0₂), solvents, such as water, acetone, isopropyl alcohol (IP A), ethanol, and/or tetrahydrofuran (THF), heating the semiconductor material to a temperature no higher than 800°C, or a combination thereof.

[0029] The method 100 further includes the step of providing a phosphorous-comprising dopant (step 104), which step may be performed before, during or after the step of providing the semiconductor material. Methods for fabricating such a dopant are described in more detail in reference to FIG. 6. In an exemplary embodiment of the present invention, the dopant is formulated so that it can be printed to form fine or small features, such as lines, dots, circles, squares, or other geometric shapes. In one exemplary embodiment of the invention, the dopant is formulated so that features having at least one dimension of less than about 200 μηι can be printed. In another exemplary embodiment of the invention, the dopant is formulated so that features having at least one dimension less than about 100 μι^η can be printed. In a preferred embodiment of the present invention, the dopant is formulated so that features having a dimension of less than about 20 μηι can be printed. In another exemplary embodiment, during the printing process and during pausing of the printing process, the dopant results in minimal, if any, clogging of the inkjet printer nozzles. Clogging of the nozzles results in down-time of the printer, thus reducing throughput. In a further exemplary embodiment, the ink is formulated so that, after it is deposited on the substrate and hiffh-temnerature annealine ( discussed in more detail below) is performed, the resulting doped region has a sheet resistance in the range of no less than about 1 ohms/square (Ω/sq.)·

[0030] In particular, the dopants contemplated herein are formulated with substantially no silanes, that is, the dopants have less than 0.1 weight percent (wt.%) silanes, oligomers and/or polymers derived from silanes, or a combination thereof. Preferably, the dopants contemplated herein have no silanes, oligomers and/or polymers derived from silanes, or a combination thereof. As noted above, the use of silanes, such as in a sol-gel process, for forming liquid dopants demonstrates a number of drawbacks. For example, at room temperature the molecular weight of the dopant formed from silanes tends to continue to increase with time. The increasing molecular weight of the dopant causes gelling of the dopant. Thus, the dopant is unstable and must be transferred and stored at low temperatures. In contrast, because the dopants contemplated herein are not formed using silanes, they have stable molecular weights. Accordingly, they can be transferred and stored at room temperature. Further, because the molecular weights are stable, gelling does not occur during use, and the dopants will not cause clogging of the nozzles of inkjet printers or the screens of screen printers during printing. In addition, the sol-gel process typically requires a solvent or solvent system that can be costly, unsafe during manufacture, and environmentally unfriendly. In contrast, as described below, the dopants contemplated herein can utilize an aqueous system. Further, the line widths of the dopants formed using silanes are more difficult to control than the line widths of the dopants contemplated herein, particularly when printing smaller feature sizes. The silane-formed dopants are also more costly and complex to manufacture, due in part to the hydrolysis and polymerization steps, compared to the dopants contemplated herein.

[0031] Referring momentarily to FIG. 6, in accordance with an exemplary embodiment of the present invention, a method 150 for fabricating a phosphorous-comprising dopant, such as that used in the method of FIG. 5, includes the step of providing a phosphorous source (step 152). Phosphorous-comprising dopants used in the method of FIG. 5 may be manufactured using a variety of inorganic or organic non-metal-comprising phosphorous sources. In a preferred embodiment of the invention, the phosphorous source is an inorganic, non-metal, phosphorous-comprising acid, phosphorous-comprising salt, or a combination thereof. Examples of inorganic and organic phosphorous-comprising acids include, but are not limited to, phosphoric acid (H₃P0₄), phosphorous acid (H₃P0₃), hypophosphorous acid

1 2

(H₃P0₂), pyrophosphoric acid (H₄P₂0₇), and acids having the formula HR R P0₂ and H-. PO^ where R_ R¹. and R² are alkvls. arvls. or combinations thereof. Examples of inorganic and organic phosphorous-comprising salts include, but are not limited to, ammonium phosphate ((NH₄)₃P0₄), ammonium dihydrogen phosphate (NH H₂P0₄,), diammonium hydrogen phosphate ((NH )₂HP0₄), ammonium phosphite ((NH₄)₃P0₃), diammonium hydrogen phosphite ((NH₄)₂HP0₃), ammonium dihydrogen phosphite (NH₄H₂P0₃), ammonium hypophosphite ((NH₄)₃P0₂), diammonium hydrogen hypophosphite ((NH₄)₂HP0₂), ammonium dihydrogen hypophosphite (NH₄H₂P0₂), ammonium pyrophosphate ((NH₄)₄P₂0₄), triammonium hydrogen pyrophosphate ((NH₄)₃HP₂0₄), diammonium dihydrogen pyrophosphate ((NH₄)₂H₂P₂0₄), ammonium trihydrogen pyrophosphate (NH H₃P₂0₄), and phosphate salts having the formula (NR R⁴R⁵R⁶)₃P0₄, (NR³R⁴R⁵H)₃P0₄, (NR³R⁴H₂)₃P0₄, and (NR³¾)₃P0₄, where R³, R⁴, R⁵, and R⁶ are each independently alkyls, aryls, or combinations thereof. Alternatively, a phosphorous-comprising salt can be formed, such as in a liquid medium and/or an alkaline material described in more detail below, to form a phosphorous-comprising source. The phosphorous concentration of a resulting doped region in a semiconductor material depends, at least in part, on the concentration of the phosphorous in the phosphorous-comprising dopant. However, while it may be preferable to have as high a concentration of the phosphorous as is possible in the dopant without instability problems, in one embodiment of the invention, the phosphorous source is present in the phosphorous-comprising dopant so that the dopant has a pH in the range of from about 0 to about 10. In this regard, the pH of the phosphorous-comprising dopant can be controlled so as to minimize the corrosive effects of the dopant on the nozzle and/or any other part of a printer. In a preferred embodiment, the phosphorous-comprising dopant has a pH of about from 1 to 7. In another embodiment of the invention, the phosphorous weight percent of the phosphorous source comprises no greater than about 60% by weight of the phosphorous-comprising dopant.

[0032] The method further includes combining the phosphorous source with an alkaline material, a liquid medium, or both an alkaline material and a liquid medium (step 154). Examples of liquid mediums suitable for use in formulating the phosphorous-comprising dopant include alcohol solvents, such as methanol, ethanol, propanol, 2-propanol, isopropanol (IPA), butanol, pentanol, and ethylene glycol, 1,2,6-hexanetriol, β-phenylethyl alcohol, polyethylene glycols; phenolic solvents, such as phenol and cresol; ethers and derivatives thereof, such as diethylene glycol monomethyl ether, triethylene glycol monomethyl ether, tetrahydrofuran (THF), dioxane, trioxane, , diethylene glycol monobutyl ether acetate, propylene glycol methyl ether acetate (PGMEA); ketones solvents and derivatives thereof, such as acetone, methvl acetone, 2-phetanone, cyclohexanone, 2,5- hexanedione, acetonylacetone, diacetone alcohol; acid solvents and derivatives thereof, such as formic acid, acetic acid, propionic acid, oleic acid, N-methylpyrrolidone (NMP), dimethyl formamide (DMF), diethylene glycol acetate, glyceryl triacetate; water, and mixtures thereof. In one exemplary embodiment, the liquid medium comprises no greater than about 95% by volume of the phosphorous-comprising dopant.

[0033] Alkaline materials may be used in the phosphorous-comprising dopant to at least partially neutralize the phosphorous source so that the resulting dopant has a pH in the range of from about 0 to about 10. In one exemplary embodiment, the alkaline material (or the cations therefrom) is present in the resulting dopant so that the dopant has a pH in the range of from about 1 to about 7. In another exemplary embodiment, the alkaline material comprises no greater than about 50% by weight of the phosphorous-comprising dopant. Alkaline materials suitable for use in forming the phosphorous-comprising dopant include any non-metal alkaline materials that are soluble in the liquid medium, if present. Examples of alkaline materials suitable for use in the phosphorous-comprising dopant include, but are not limited to, ammonium alkaline materials such as ammonium hydroxide (NH₄)OH, and hydrocarbon group-comprising alkaline materials such as, for example, (NR⁷R⁸R⁹R¹⁰)OH, ( R⁷R⁸R⁹H)OH, (NR⁷R⁸H₂)OH, (NR⁷H₃)OH, where R⁷, R⁸, R⁹, and R¹⁰ are each independently alkyls, aryls, or the like, or any combination thereof.

[0034] The phosphorous source and the liquid medium and/or the alkaline material are mixed using any suitable mixing or stirring process that forms a mixture. For example, a reflux condenser, a low speed sonicator or a high shear mixing apparatus, such as a homogenizer, a microfluidizer, a cowls blade high shear mixer, an automated media mill, or a ball mill, may be used for several seconds to an hour or more to form the phosphorous- comprising dopant. It will be appreciated that, while the phosphorous source, the liquid medium and the alkaline material can be in the form of separate components added together, it will be appreciated that two or more of the components can be combined together first, followed by the addition of the third component. For example, the alkaline material may be provided in the form of an aqueous alkaline material composition, in which the water portion of the composition comprises at least a portion of the liquid medium of the resulting dopant. Alternatively, the phosphorous source may be provided in the form of an aqueous phosphorous source composition, in which the water portion of the composition comprises at least a portion of the liquid medium of the resulting dopant.

[0035] In an optional exemplary embodiment of the invention, a functional additive is added to the ohosohorous source before, during, and/or after combination with the liquid medium and/or the alkaline material (step 156). For example, it may be desirable to minimize the amount of the resulting phosphorous-comprising dopant that spreads beyond the penned area, that is, the area upon which the dopant is deposited, into unpenned areas of the semiconductor material before the predetermined annealing temperature of the annealing process is reached. Spreading of the phosphorous and/or phosphorous-comprising dopant beyond the penned area into unpenned areas before annealing can significantly affect the electrical characteristics of the resulting semiconductor device that utilizes the subsequently- formed doped region. Thus, in a further exemplary embodiment, a viscosity modifier is added. Examples of such viscosity-modifiers include celluloses, glycerol, polyethylene glycol, polypropylene glycol, ethylene glycol/propylene glycol copolymer, organo-modified siloxanes, ethylene glycol/siloxane copolymers, polyelectrolyte, oleic acid and the like, and combinations thereof. Examples of other suitable additives that may be used to form the phosphorous-comprising dopant include dispersants, surfactants, polymerization inhibitors, wetting agents, antifoaming agents, detergents and other surface-tension modifiers, flame retardants, pigments, plasticizers, thickeners, rheology modifiers, and mixtures thereof.

[0036] In another exemplary embodiment of the present invention, silica particles may be added to the phosphorous-comprising dopant to modify the viscosity, surface tension, and/or wettability of the dopant and thereby permit deposition of the dopant on the semiconductor material so that features with very fine dimensions can be achieved. FIG. 7 illustrates a method 200 for fabricating a phosphorous-comprising dopant, such as that used in the method of FIG. 5, in accordance with another exemplary embodiment of the invention. As with method 150 of FIG. 6, method 200 includes the step of providing a phosphorous source (step 202). Any of the phosphorous sources described above with respect to step 152 of method 150 can be used. The phosphorous source is combined with an alkaline material (step 204). Any of the alkaline materials described above with reference to step 154 of method 150 can be used and any of the methods discussed above for combining the components may be used. A liquid medium, such as any of the liquid mediums set forth above, also can be added to the phosphorous source.

[0037] Method 200 further includes combining silica particles with a liquid medium (step 206). The silica particles may include any silica particles that have an average particle size of no greater than 100 μιη, preferably no greater than 1 μηι, and that modify the viscosity, surface tension, and/or wettability of the dopant. The term "particle size" includes a diameter, a length, a width or any other suitable dimension used to characterize a size of a silira narticle in non-aeereeate form as measured using transmission electron microscopy (TEM). Examples of silica particles suitable for use include sol-gel particles, such as those available from FOSO CHEMICAL of Japan, and, preferably, fumed silica particles, such as those from the Aerosil® series, available from Evonik Degussa Gmbh of Frankfurt, Germany, the CAB-O-SIL^® series from Cabot Corporation of Billerica, Massachusetts; and the HDK^® series available from Wacker Chemie AG of Germany; and other oxide particles. The liquid medium may comprise any of the liquid mediums set forth above for step 154 of method 150 and may be combined with the silica particles using any of the methods for combining set forth above.

[0038] In one contemplated embodiment, the phosphorous-comprising dopant may be formed from non-treated silica particles, treated silica particles, or a combination thereof. In this regard, the resulting phosphorous-comprising dopant exhibits a thixotropic property minimizes "out-diffusion" of the dopant. As used herein, the term "non-treated silica particle" means a silica particle with a surface that has not been modified with organic and/or inorganic functional groups. A "treated silica particle" is a silica particle with a surface that has been at least partially modified by organic and/or inorganic functional groups. Examples of non-treated silica particles include, but are not limited to, Aerosil® 380, Aerosil® 200, and Aerosil® 150, available from Evonik Degussa Gmbh, CAB-O-SIL^® M-5/M-5P, HP 60, and EH-5, available from Cabot Corporation; WACKER HDK - N20, and HDK^® V15/V15P, available from Wacker Chemie AG; and Quartron PL-06L, available from FOSO CHEMICAL. Examples of treated particles include, but are not limited to, Aerosil® R816, Aerosil® R812, Aerosil® R972, and Aerosil® R974, available from Evonik Degussa Gmbh, CAB-O-SIL® TS 610, and CAB-O-SIL® H-300, available from Cabot Corporation, and HDK-H15 and HDK-H20, available from Wacker Chemie AG, and Quartron PL-2L-PGME, available from FUSO CHEMICAL. A thixotropic property of the dopant can be realized through the formation of a silica particle grid by polarity matching of the solvent system with the selection of silica particles. Such combination can involve one type or multiple types of silica particles with similar and/or different polarities. When applying a shearing force, such silica particle grid is broken into smaller pieces, leading to a drop in viscosity. When the shearing force is removed, the silica particle grid is reestablished and the viscosity increases.

[0039] After combination of the silica particles and the liquid medium, the phosphorous source/alkaline material combination and the particles/liquid medium combination can be mixed, using any of the methods described above, to form the phosphorous-comprising donant ( sten 208V In one embodiment of the invention, the phosphorous-comprising dopant has a pH in the range of from about 0 to about 10. In a preferred embodiment, the phosphorous-comprising dopant has a pH of from about 1 to 7. In another embodiment of the invention, the phosphorous weight percent from the phosphorous source comprises no greater than about 60% by weight of the phosphorous-comprising dopant, the alkaline material comprises greater than zero and no greater than about 50% by weight of the phosphorous-comprising dopant, the liquid medium comprises about greater than zero and no greater than about 60% by volume of the phosphorous-comprising dopant, and the silica particles comprise no greater than about 0.1% to about 40% by weight of the phosphorous- comprising dopant. While method 200 illustrates that the phosphorous source and the alkaline material are combined to form a first combination and the silica particles and the liquid medium are combined to form a second combination with the first and second combinations then mixed to form the dopant, it will be understood that the phosphorous source, the alkaline material, the silica particles and the liquid medium can be combined in any suitable sequence that satisfactorily forms the phosphorous-comprising dopant. In an optional exemplary embodiment of the invention, a functional additive is added to the phosphorous source before, during, or after combination with the alkaline material, the silica particles and/or the liquid medium (step 210).

[0040] Depending on the liquid medium and/or alkaline material used in the dopant, the phosphorous source may or may not disassociate to form inorganic, non-metal phosphorous- comprising anions such as, for example, H₂P0₄ ^", HP0₄ ^", P0₄ ^", H₂P0₃ ^", HP0₃ ^", P0₃ H₂P0₂ ^", HP0₂ ^2", P0₂ ^3", H₃P₂0₄\ H₂P₂0₄ ^2", HP₂0₄ ^3', P₂0₄ ^4", RⁿR¹²P0₂\ HRP0₃ ^", and Pv^UP0₃ ^2", where R¹¹ and R¹² are alkyls, aryls, or combinations thereof. In addition, the amount of liquid medium and/or alkaline material used may determine, at least in part, the extent of dissociation of the phosphorous source. Further, the interaction of the liquid medium and the alkaline material may determine, at least in part, the extent to which the alkaline material disassociates to form cations and hydroxide anions. Accordingly, upon formation, the phosphorous-comprising dopant may comprise a phosphorous-comprising salt, a phosphorous comprising acid, phosphorous-comprising anions, or combinations thereof, an alkaline material and/or cations from an alkaline material, and/or a liquid medium and, optionally, a functional additive.

[0041] Referring back to FIG. 5, the method 100 continues with the application of the phosphorous-comprising dopant overlying the semiconductor material (step 106). As used herein, the term "overlying" encompasses the terms "on" and "over". Accordingly, the dnnant can he annlied directlv onto the semiconductor material or may be deposited over the semiconductor material such that one or more other materials are interposed between the dopant and the semiconductor material. Examples of materials that may be interposed between the dopant and the semiconductor material are those materials that do not obstruct diffusion of the phosphorous elements of the phosphorous-comprising dopant into the semiconductor material during annealing. Such materials include phosphosilicate glass, borosilicate glass, silicon nitride, or silicon oxide that forms on a silicon material. Typically such materials are removed before dopants are deposited on the silicon material; however, in various embodiments, it may be preferable to omit the removal process, thereby permitting the materials to remain on the semiconductor material.

[0042] In an exemplary embodiment, the phosphorous-comprising dopant is applied overlying at least a portion of the semiconductor material using a non-contact process printer. In this regard, the phosphorous-comprising dopant is applied overlying the semiconductor material in a pattern that is stored in or otherwise supplied to the printer. An example of an inkjet printer suitable for use includes, but is not limited to, Dimatix Inkjet Printer Model DMP 2831 available from Fujifilm Dimatix, Inc. of Santa Clara, California. An example of an aerosol jet printer suitable for use includes, but is not limited to, the M3D Aerosol Jet Deposition System available from Optomec, Inc. of Albuquerque, New Mexico. In another exemplary embodiment, the phosphorous-comprising dopant is applied overlying at least a portion of the semiconductor material by screen printing, spraying, spinning, or rolling the dopant, as described above. Preferably, the dopant is applied to the substrate at a temperature in the range of about 15°C to about 350°C in a humidity of about 20 to about 80%.

[0043] Once the dopant is applied overlying the semiconductor material, the liquid medium in the dopant and any water that formed from the reaction of hydrogen cations (from a phosphorous-comprising acid) and hydroxide anions (from an alkaline material) is caused to evaporated (step 108). In this regard, the liquid medium and/or water may be permitted to evaporate at room temperature (about 16°C to about 28°C) or may be heated to the boiling point of the liquid medium for a sufficient time to permit the liquid medium to evaporate. Preferably, the liquid medium and/or water is evaporated at a temperature no greater than 800°C.

[0044] After the pattern of phosphorous-comprising dopant is formed on the semiconductor material, phosphorous elements, in an ionic state, as part of a compound, or as a combination of both, of the dopant are caused to diffuse into the semiconductor material Csteo 1 10). In an exemplary embodiment, the semiconductor material is subjected to a high-temperature thermal treatment or "anneal" to cause the phosphorous elements of the phosphorous-comprising dopant to diffuse into the semiconductor material, thus forming phosphorous -doped regions within the material (step 1 10). The anneal can be performed using any suitable heat-generating method, such as, for example, electrical heating, infrared heating, laser heating, microwave heating, and the like. The time duration and the temperature of the anneal is determined by such factors as the initial phosphorous concentration of the phosphorous-comprising dopant, the thickness of the dopant deposit, the desired concentration of the resulting phosphorous-doped region, and the depth to which the phosphorous is to diffuse. In one exemplary embodiment, the substrate is placed inside an oven wherein the temperature is ramped up to a temperature in the range of about 800 °C to about 1200 °C and the semiconductor material is baked at this temperature for about 2 to about 180 minutes. Annealing also may be carried out in an in-line furnace to increase throughput. The annealing atmosphere may contain 0 to 100% oxygen in an oxygen/nitrogen or oxygen/argon mixture. In a preferred embodiment, the semiconductor material is subjected to an anneal temperature of about 1050°C for about from 5 to about 10 minutes in an oxygen ambient. In another embodiment, the semiconductor material is subjected to an anneal temperature of about 950°C for about 10 to about 180 minutes in an oxygen ambient. In yet another embodiment, the semiconductor material is subjected to an anneal temperature of about 850°C for about 10 to about 300 minutes in an oxygen ambient.

[0045] In an optional exemplary embodiment, the semiconductor material then is subjected to a post-diffusion treatment (step 1 14). The post-diffusion treatment removes any residues, such as, for example, phosphosilicate glass, phosphorous oxide, silicon oxide or contamination, that form during annealing of the semiconductor material. If such residue is not removed after annealing, it may have deleterious affects on the performance of a subsequently-formed device. For example, such residue may dramatically increase the contact resistance between doped semiconductor material and a metal contact formed thereon. Examples of post-diffusion treatment include subjecting the semiconductor material to acids, such as hydrofluoric acid (HF), hydrochloric acid (HC1), sulfuric acid (H₂S0₄), and/or nitric acid (HN0₃), bases, such as ammonium hydroxide ( H₄OH), sodium hydroxide (NaOH), potassium hydroxide (KOH), tetramethylammonium hydroxide (TMAH), oxidizers, such as hydrogen peroxide (H₂0₂), solvents, such as water, acetone, isopropyl alcohol (IPA), ethanol, and/or tetrahydrofuran (THF), heating the semiconductor material to a temperature no higher than 800°C, or a combination thereof. [0046] The following are examples of phosphorous-comprising dopants for use in fabricating doped regions of semiconductor materials. The examples are provided for illustration purposes only and are not meant to limit the various embodiments of the present invention in any way.

[0047] EXAMPLE 1

[0048] In a 1 liter (L) glass vessel, 8.3 parts by volume 85% phosphoric acid was combined with 33.3 parts by volume ethylene glycol and 58.3 parts by volume 25% TMAH aqueous solution. The solution was stirred at room temperature for thirty minutes using an electromagnetic stirrer. The solution then was filtered using a 0.45 μηι polyvinylidine fluoride (PVDF) filter to obtain a phosphorous-comprising dopant. The pH of the dopant was 7. The phosphorous-comprising dopant was deposited on a bare P-type silicon wafer using a 1 picoliter (pL) nozzle of a Dimatix Inkjet Printer Model DMP 2831 with 15 μιη drop spacing. The silicon wafer was baked at 200°C for about 10 minutes. A dopant line width as thin as 20 μπι on the silicon wafer was achieved.

[0049] EXAMPLE 2

[0050] Approximately 100 milliliter (mL) ethylene glycol was added to a 25Ό mL glass vessel. Approximately 1 gram (g) of Aerosil® 380 fumed silica was added to the ethylene glycol and the mixture was mixed for about 15 minutes using a Heat Systems - Ultrasonics Inc. ultrasonic processor Model W-375 to form a uniform dispersion. Approximately 100 mL deionized water was added to a 500 mL glass vessel. Approximately 150 g 50% TMAH aqueous solution and 70 mL 85% phosphoric acid aqueous solution were added to the water and the resulting solution was stirred for thirty minutes using an electromagnetic stirrer. Approximately 100 mL of the silica/ethylene glycol dispersion was combined with 100 mL of the water/TMAH/phosphoric acid solution and the mixture was stirred for approximately thirty minutes continuously using an electromagnetic stirrer to obtain a phosphorous- comprising dopant. The pH of the dopant was 7. The phosphorous-comprising dopant was deposited on a bare P-type silicon wafer using a 1 pL nozzle of a Dimatix Inkjet Printer Model DMP 2831 with 12 μιη drop spacing. The silicon wafer was baked at 200°C for about 10 minutes. A dopant line width as thin as 20 μηι on the silicon wafer was achieved.

[0051] EXAMPLE 3 [0052] In a 1 L glass vessel, 16.6 parts by volume 85% phosphoric acid aqueous solution was combined with 25.0 parts by volume ethylene glycol and 58.3 parts 25% TMAH aqueous solution. The solution was stirred at room temperature for thirty minutes using an electromagnetic stirrer. The solution then was filtered using a 0.45 μη PVDF filter to obtain a phosphorous-comprising dopant. The pH of the dopant was 2.5. The phosphorous- comprising dopant was deposited on a bare P-type silicon wafer using a 1 pL nozzle of a Dimatix Inkjet Printer Model DMP 2831 with 15 μηι drop spacing. The silicon wafer was baked at 200°C for about 10 minutes and then was subjected to a furnace at 980°C for about 3 hours. After deglazing with diluted hydrofluoric acid (DHF), a sheet resistance as low as 3.5 ohm/sq on the doped silicon wafer was achieved.

[0053] EXAMPLE 4

[0054] In a 1 L glass vessel, 40 parts by volume 85% phosphoric acid aqueous solution was neutralized with 60 parts by volume 25% TMAH aqueous solution. The solution was stirred at room temperature for thirty minutes using an electromagnetic stirrer. The solution then was filtered using a 0.45 μιη PVDF filter to obtain a phosphorous-comprising dopant. A textured P-type silicon wafer was baked at 200°C for about 20 minutes and then was allowed to cool. The phosphorous-comprising dopant was deposited on the textured silicon wafer using a 10 pL nozzle of a Dimatix Inkjet Printer Model DMP 2831 with 20 μιη drop spacing. The silicon wafer was baked at 200°C for about 10 minutes and then was baked at 350°C for 10 minutes. A 280 μηι dopant line width on the silicon wafer was achieved.

[0055] EXAMPLE 5

[0056] In a 2 L tube-type reactor, 136 parts of 85% phosphoric acid aqueous solution was neutralized by 198 parts of 25% TMAH aqueous solution. The solution was further diluted with 190 parts of deionized water and 398 parts of glycerol was added. The resulting solution was mechanically stirred at 300 rpm for 15 minutes. Gradually, 39 parts of Aerosil 380 fumed silica and 39 parts of Aerosil R 816 were added to the solution and the rotating speed was adjusted to 500 rpm. The suspension was stirred for 3 hours. The resulting phosphorous-comprising dopant was deposited on a bare P-type silicon wafer using screen printing. The wafer was baked at 300°C for about 1 minute. A dopant line width as thin as 50 μιη on the silicon wafer was achieved. m0571 EXAMPLE 6 [0058] In a 2 L glass vessel, 425 parts of 85% phosphoric acid aqueous solution was neutralized by 825 parts of 25% TMAH aqueous solution and the mixture was mechanically stirred at 200 rpm for 15 minutes. The vessel was attached to a rotary evaporator and the water inside was evaporated until the solution was 46.5% of its original weight. 2470 parts glycerol were added to the condensate and the mixture was mechanically stirred at 300 rpm for one hour. To the solution, 74.8 g of Aerosil 380 fumed silica and 74.8 g of CAB-O-SIL TS-610 fumed silica were slowly added so that the two fumed silicas were fully dispersed in the solution. The mixture was mechanically stirred at 800 rpm for 8 hours. The phosphorous-comprising dopant was deposited on a bare P-type silicon wafer using screen printing. The wafer was baked at 300°C for about 1 minute. A dopant line width as thin as 50 μηι on the silicon wafer was achieved.

[0059] EXAMPLE 7

[0060] Into 136 parts of 85% phosphoric acid aqueous solution in a 1 L flask, 39 parts 39 parts CAB-O-SIL TS-380 was slowly added using mechanical stirring. The suspension was stirred at 500 rpm for 20 minutes and the vessel then was heated to 100°C for five hours. The suspension was neutralized with 198 parts 25% TMAH aqueous solution and then combined with 190 parts deionized water and 398 parts glycerol. 39 parts Aerosil 200 was added to the suspension to adjust its final viscosity. The suspension was stirred at 1200 rpm for 5 hours. The phosphorous-comprising dopant was deposited on a bare P-type silicon wafer using screen printing. The wafer was baked at 300°C for about 1 minute. A dopant line width as thin as 50 μιη on the silicon wafer was achieved.

[0061] EXAMPLE 8

[0062] In a 2 L tube-type reactor, 136 parts of 85%) phosphoric acid aqueous solution was neutralized with 198 parts of 25% TMAH aqueous solution. The solution was combined with 190 parts deionized water and 398 parts glycerol and mechanically stirred at 300 rpm for 15 minutes. Gradually, 39 parts Aerosil 380 fumed silica, 10 parts 2-hydroxyethyl cellulose, and 29 parts Aerosil R816 were added to the solution. The suspension was stirred at 500 rpm for 3 hours until it became semi-transparent. The phosphorous-comprising dopant was deposited on a bare P-type silicon wafer using screen printing. The wafer was baked at 300°C for about 1 minute. A dopant line width as thin as 50 μιη on the silicon wafer was achieved. [0063] EXAMPLE 9

[0064] In a 2 L flask, 10 parts hydroxyethyl cellulose, 2 parts Titanate Coupling Agent TC-WT available from Anhui TaiChang Chemical of China, 39 parts Aerosil R812, 136 parts 85% phosphoric acid aqueous solution, and 398 parts glycerol were combined using mechanical stirring. The suspension was stirred at 500 rpm for 20 minutes and heated to 100°C for 1 hour. The suspension became viscous and 130 parts deionized water and 60 parts ammonia were added to reduce the viscosity. Next, 39 parts Aerosil 150 was added to adjust the final viscosity. The rotating speed was adjusted to 1500 rpm and the suspension was stirred for 3 hours. The phosphorous-comprising dopant was deposited on a bare P- type silicon wafer using screen printing. The wafer was baked at 300°C for about 1 minute. A dopant line width as thin as 50 μπι on the silicon wafer was achieved.

[0065] EXAMPLE 10

[0066] In a 2 L tube-type reactor, 136 parts of 85% phosphoric acid aqueous solution was neutralized with 198 parts of 25% TMAH aqueous solution. The solution was combined with 190 parts deionized water and 398 g of glycerol and mechanically stirred at 300 rpm for 15 minutes. Gradually, 37 parts of Aerosil 380 fumed silica, 30 parts of Aerosil R972, and 9 parts of Aerosil R816 were added to the solution. The suspension was stirred at 500 rpm for 3 hours. The phosphorous-comprising dopant was deposited on a bare P-type silicon wafer using screen printing. The wafer was baked at 300°C for about 1 minute. A dopant line width as thin as 50 μηι on the silicon wafer was achieved.

[0067] Accordingly, substantially silane-free phosphorous-comprising dopants for forming phosphorous-doped regions in semiconductor materials, methods for fabricating such phosphorous-comprising dopants, and methods for forming phosphorous-doped regions in semiconductor material using such phosphorous-comprising dopants have been provided. While at least one exemplary embodiment has been presented in the foregoing detailed description of the invention, it should be appreciated that a vast number of variations exist. It should also be appreciated that the exemplary embodiment or exemplary embodiments are only examples, and are not intended to limit the scope, applicability, or configuration of the invention in any way. Rather, the foregoing detailed description will provide those skilled in the art with a convenient road map for implementing an exemplary embodiment of the invention, it being understood that various changes may be made in the function and arrangement of elements described in an exemplary embodiment without departing from the scope of the invention as set forth in the appended claims and their legal equivalents.

Claims

CLAIMS What is claimed is:

1. A phosphorous-comprising dopant comprising:

a phosphorous source comprising a phosphorous-comprising salt, a phosphorous- comprising acid, inorganic, non-metal phosphorous-comprising anions, or combinations thereof;

an alkaline material, cations from an alkaline material, or combinations thereof; and a liquid medium;

wherein the phosphorous-comprising dopant comprises less than 0.1 wt. % silanes, oligomers and/or polymers derived from silanes, or a combination thereof.

2. The phosphorous-comprising dopant of claim 1 , wherein the phosphorous source comprise an inorganic, non-metal, phosphorous-comprising acid, an inorganic, non-metal, phosphorous-comprising salt, or combinations thereof.

3. The phosphorous-comprising dopant of claim 1 , wherein the phosphorous source comprises a phosphorous-comprising acid selected from the group consisting of phosphoric acid (H₃P0₄), phosphorous acid (H₃P0₃), hypophosphorous acid (H₃P0₂), pyrophosphoric acid (H₄P₂0₇), and acids having a formula HR'R²P0₂ and H₂RP0₃, where R, R¹ , and R² are each independently alkyls, aryls, or combinations thereof.

4. The phosphorous-comprising dopant of claim 1 , wherein the phosphorous source comprises the phosphorous-comprising salt selected from the group consisting of ammonium phosphate ((NH₄)₃P0₄), ammonium dihydrogen phosphate ( H₄H₂P0₄,), diammonium hydrogen phosphate ((NH₄)₂HP0₄), ammonium phosphite ((NH₄)₃P0₃), diammonium hydrogen phosphite ((NH₄)₂HP0₃), ammonium dihydrogen phosphite (NH₄H₂P0₃), ammonium hypophosphite ((NH₄)₃P0₂), diammonium hydrogen

hypophosphite ((NH₄)₂HP02), ammonium dihydrogen hypophosphite (NH₄H₂P0₂), ammonium pyrophosphate ((NH₄)₄P₂0₄), triammonium hydrogen pyrophosphate

((NH₄)₃HP₂0₄), diammonium dihydrogen pyrophosphate ((NH₄)₂H₂P₂0₄), ammonium trihydrogen pyrophosphate (NH₄H₃P₂0₄), and phosphate salts having a formula

(NR³R⁴R⁵R⁶)₃P0₄, (NR³R⁴R⁵H)₃P0₄, (NR³R⁴H₂)₃P0₄, and (NR³H₃)₃P0₄, where R³, R⁴, R⁵, and R⁶ are each indenendentlv alkvls. arvls. or combinations thereof.

5. The phosphorous-comprising dopant of claim 1, wherein the phosphorous- comprising dopant has a pH in a range of from about 0 to about 10.

6. The phosphorous-comprising dopant of claim 1, wherein a phosphorous weight percent of the phosphorous source comprises no greater than about 60% by weight of the phosphorous-comprising dopant.

7. The phosphorous-comprising dopant of claim 1 , wherein the liquid medium is selected from the group consisting of methanol, ethanol, propanol, 2-propanol, isopropanol (IP A), butanol, pentanol, ethylene glycol, 1 ,2,6-hexanetriol, β-phenylethyl alcohol, polyethylene glycols, phenol, cresol, diethylene glycol monomethyl ether, triethylene glycol monomethyl ether, tetrahydrofuran (THF), dioxane, trioxane, diethylene glycol monobutyl ether acetate, propylene glycol methyl ether acetate (PGMEA), acetone, methyl acetone, 2- phetanone, cyclohexanone, 2,5-hexanedione, acetonylacetone, diacetone alcohol, formic acid, acetic acid, propionic acid, oleic acid, N-methylpyrrolidone (NMP), dimethyl formamide (DMF), diethylene glycol acetate, glyceryl triacetate, water, and combinations thereof.

8. The phosphorous-comprising dopant of claim 1, wherein the alkaline material comprises greater than about zero and no greater than about 50% by weight of the phosphorous-comprising dopant.

9. The phosphorous-comprising dopant of claim 1, wherein the alkaline material comprises an ammonium alkaline material.

10. The phosphorous-comprising dopant of claim 1, further comprising silica particles having an average particle size of no greater than about 100 μιη.

1 1. The phosphorous-comprising dopant of claim 10, wherein the silica particles have an average particle size of no greater than about 1 μιη.

12. The phosphorous-comprising dopant of claim 11 , wherein the silica particles comnrise treated silica Darticles. non-treated silica particles, or combinations thereof.

13. A method for forming phosphorous-doped regions in a semiconductor material, the method comprising the steps of:

providing a phosphorous-comprising dopant formed using a phosphorous- comprising acid, a phosphorous-comprising salt, or combinations thereof and an alkaline material, cations from an alkaline material, or combinations thereof in a liquid medium, wherein the phosphorous-comprising dopant comprises less than 0.1 wt. % silanes, oligomers and/or polymers derived from silanes, or a combination thereof;

depositing the phosphorous-comprising dopant overlying at least a portion of the semiconductor material;

causing the liquid medium of the phosphorous-comprising dopant to evaporate; and diffusing phosphorous elements derived from the phosphorous-comprising dopant into the semiconductor material.

14. The method of claim 13, wherein the step of providing comprises the step of providing the phosphorous-comprising dopant formed using the phosphorous-comprising acid selected from the group consisting of phosphoric acid (H₃P0₄), phosphorous acid (H₃P0₃), hypophosphorous acid (H₃P0₂), pyrophosphoric acid (H₄P₂0₇), and acids having a formula HR¹R²P0₂ and H₂RP0₃, where R, R¹, and R² are each independently alkyls, aryls, or combinations thereof.

15. The method of claim 13, wherein the step of providing comprises the step of providing the phosphorous-comprising dopant formed using the phosphorous-comprising salt selected from the group consisting of ammonium phosphate ((NH₄)₃P0₄), ammonium dihydrogen phosphate (NH₄H₂P0₄,), diammonium hydrogen phosphate ((NH₄)₂HP0₄), ammonium phosphite ((NH₄)₃P0₃), diammonium hydrogen phosphite ((NH₄)₂HP0₃), ammonium dihydrogen phosphite (NH₄H₂P0₃), ammonium hypophosphite ((NH₄)₃P0₂), diammonium hydrogen hypophosphite ((NH₄)₂HP0₂), ammonium dihydrogen

hypophosphite (NH₄H₂P0₂), ammonium pyrophosphate ((NH₄)₄P₂0₄), triammonium hydrogen pyrophosphate ((NH₄)₃HP₂0₄), diammonium dihydrogen pyrophosphate

((NH₄)₂H₂P₂0₄), ammonium trihydrogen pyrophosphate (NH₄H₃P₂0₄), and phosphate salts having a formula (NR³R⁴R⁵R⁶)₃P0₄, (NR³R⁴R⁵H)₃P0₄, (NR³R⁴H₂)₃P0₄, and (NR³H₃)₃P0₄, where R³, R⁴, R⁵, and R⁶ are each independently alkyls, aryls, or combinations thereof.

16. The method of claim 13, wherein the step of providing comprises the step of providing the phosphorous-comprising dopant formed using the phosphorous-comprising acid, the phosphorous-comprising salt, or the combinations thereof in the liquid medium wherein the liquid medium is selected from the group consisting of methanol, ethanol, propanol, 2-propanol, isopropanol (IP A), butanol, pentanol, ethylene glycol, 1 ,2,6- hexanetriol, β-phenylethyl alcohol, polyethylene glycols, phenol, cresol, diethylene glycol monomethyl ether, triethylene glycol monomethyl ether, tetrahydrofuran (THF), dioxane, trioxane, diethylene glycol monobutyl ether acetate, propylene glycol methyl ether acetate (PGMEA), acetone, methyl acetone, 2-phetanone, cyclohexanone, 2,5-hexanedione, acetonylacetone, diacetone alcohol, formic acid, acetic acid, propionic acid, oleic acid, N- methylpyrrolidone (NMP), dimethyl formamide (DMF), diethylene glycol acetate, glyceryl triacetate, water, and combinations thereof.

17. The method of claim 13, wherein the step of providing comprises the step of providing the phosphorous-comprising dopant further formed using an ammonium alkaline material.

18. The method of claim 13, wherein the step of providing comprises the step of providing the phosphorous-comprising dopant further formed using silica particles having an average particle size of no greater than about 100 μιη.

19. The method of claim 13, wherein the step of diffusing comprises the step of annealing the semiconductor material using high-temperature thermal annealing, laser annealing, or microwave annealing.

20. The method of claim 13, further comprising, before the step of depositing, the step of subjecting the semiconductor material to a pre-dopant treatment.

21. The method of claim 20, wherein the step of subjecting the semiconductor material to the pre-dopant treatment comprises cleaning a surface of the semiconductor material; heating a surface of the semiconductor material; oxidizing a surface of the semiconductor material; or a combination thereof.

22. The method of claim 13, further comprising, after the step of diffusing, the step of subjecting the semiconductor material to a post-diffusion treatment.

23. The method of claim 22, wherein the step of subjecting the semiconductor material to the post-diffusion treatment comprises subjecting the semiconductor material to an acid, a base, an oxidizer, a solvent, or combinations thereof.

24. The method of claim 13, wherein the step of providing comprises the step of providing the phosphorous-comprising dopant further formed using treated silica particles, non-treated silica particles, or combinations thereof.

25. A method of forming a phosphorous-comprising dopant, the method comprising the steps of:

providing a phosphorous source comprising a phosphorous-comprising acid, a phosphorous-comprising salt, or combinations thereof; and

combining the phosphorous source with an alkaline material and a liquid medium; wherein the phosphorous-comprising dopant comprises less than 0.1 wt. % silanes, oligomers and/or polymers derived from silanes, or a combination thereof.

26. The method of claim 25, wherein the step of providing comprises providing the phosphorous source comprising the phosphorous-comprising acid selected from the group consisting of phosphoric acid (H₃P0₄), phosphorous acid (H₃P0₃), hypophosphorous acid

1

(H₃P0₂), pyrophosphoric acid (H₄P₂0₇), and acids having a formula HR R P0₂ and

H₂RP0₃, where R, R¹, and R² are each independently alkyls, aryls, or combinations thereof.

27. The method of claim 25, wherein the step of providing comprises providing the phosphorous source comprising the phosphorous-comprising salt selected from the group consisting of ammonium phosphate ((NH₄)₃P0₄), ammonium dihydrogen phosphate (NH₄H₂P0₄,), diammonium hydrogen phosphate ((NH₄)₂HP04), ammonium phosphite ((NH₄)₃P0₃), diammonium hydrogen phosphite ((NH₄)₂HP0₃), ammonium dihydrogen phosphite (NH₄H₂P0₃), ammonium hypophosphite ((NH₄)₃P0₂), diammonium hydrogen hypophosphite ((NH₄)₂HP0₂), ammonium dihydrogen hypophosphite (NH₄H₂P0₂), ammonium pyrophosphate ((NH₄)₄P₂0₄), triammonium hydrogen pyrophosphate

ftTsJH,V.HPiOA diammnninm dihvdroeen DVroDhosohate ((ΝΗ< )?Η?Ρ;>0₄), ammonium trihydrogen pyrophosphate (NH₄H3P₂0₄), and phosphate salts having a formula

(NR³R⁴R⁵R⁶)₃P0₄, (NR³R⁴R⁵H)₃P0₄, (NR³R⁴H₂)₃P0₄, and (NR³H₃)₃P0₄, where R³, R⁴, R⁵, and R⁶ are each independently alkyls, aryls, or combinations thereof.

28. The method of claim 25, wherein the step of combining comprises combining the phosphorous source with the liquid medium selected from the group consisting of methanol, ethanol, propanol, 2-propanol, isopropanol (IP A), butanol, pentanol, ethylene glycol, 1 ,2,6- hexanetriol, β-phenylethyl alcohol, polyethylene glycols, phenol, cresol, diethylene glycol monomethyl ether, triethylene glycol monomethyl ether, tetrahydrofuran (THF), dioxane, trioxane, diethylene glycol monobutyl ether acetate, propylene glycol methyl ether acetate (PGMEA), acetone, methyl acetone, 2-phetanone, cyclohexanone, 2,5-hexanedione, acetonylacetone, diacetone alcohol, formic acid, acetic acid, propionic acid, oleic acid, N- methylpyrrolidone (NMP), dimethyl formamide (DMF), diethylene glycol acetate, glyceryl triacetate, water, and combinations thereof.

29. The method of claim 25, wherein the step of combining comprises combining the phosphorous source with an ammonium alkaline material.

30. The method of claim 25, further comprising the step of combining the phosphorous source with silica particles having an average particle size of no greater than about 100 μηι.

31. The method of claim 25, further comprising the step of combining the phosphorous source with treated silica particles or non-treated silica particles, or combinations thereof.

32. A phosphorous-comprising dopant comprising:

a phosphorous source comprising a phosphorous-comprising salt, a phosphorous- comprising acid, phosphorous-comprising anions, or combinations thereof;

an alkaline material, cations from an alkaline material, or combinations thereof; a liquid medium; and

silica particles.

33. The phosphorous-comprising dopant of claim 32, wherein the silica particles comprise treated silica particles, non-treated silica particles, or combinations thereof.

34. A phosphorous-comprising dopant comprising:

a hydrocarbon group-comprising alkaline material, cations from a hydrocarbon group-comprising alkaline material, or combinations thereof;

a liquid medium; and

silica particles.

35. The phosphorous-comprising dopant of claim 34, wherein the hydrocarbon group- comprising alkaline material is selected from the group consisting of (NR R R R )OH, (NR⁷R⁸R⁹H)OH, (NR⁷R⁸H₂)OH, and (NR⁷H₃)OH, where R⁷, R⁸, R⁹, and R¹⁰ are each independently alkyls, aryls, or combinations thereof.