CN218025871U

CN218025871U - Graphite assembly

Info

Publication number: CN218025871U
Application number: CN202220599252.0U
Authority: CN
Inventors: 吴宗丰; 李文亮; 周冠廷; 蔡宇砚; 苏修贤; 赖泱蓉; 邱国扬; 曾涵芸; 游辉桓; 张家文; 吕椬境
Original assignee: FEEDBACK TECHNOLOGY CORP
Current assignee: FEEDBACK TECHNOLOGY CORP
Priority date: 2021-03-29
Filing date: 2022-03-18
Publication date: 2022-12-13
Anticipated expiration: 2032-03-18
Also published as: CN115141036A

Abstract

A graphite assembly comprises a graphite substrate and at least one graphite film. The graphite film is arranged on the graphite substrate. Wherein the hardness of the graphite film is more than twice of the hardness of the graphite substrate. Improve the surface characteristic of spare part by a wide margin, it has outstanding adhesion, has advantages such as low resistance, heat conduction and thermal diffusivity are strong, the beneficial effects of the utility model are that, can improve the defect on substrate or the cladding material, restrain the emergence of particle for promote the yield of processing procedure.

Description

Graphite assembly

Technical Field

The present invention relates to a process for maintaining high cleanliness in industries of optoelectronic and semiconductor, such as IC manufacturing, liquid crystal display panel, light emitting diode, micro electro mechanical system, solar panel, electronic paper, etc., and particularly to a graphite component used in any type of graphite component, especially ion implantation process, in optoelectronic and semiconductor industries. The technique of the utility model can form a graphite protective film with high hardness and low porosity on the surface of the graphite component, thereby improving the process yield and prolonging the service life of the graphite component.

Background

Graphite parts are widely used in various semiconductor processes, such as graphite crucibles, graphite carrier plates, and semiconductor ion implantation path components, due to their characteristics of high temperature resistance, high thermal conductivity, low expansion coefficient, etc. However, graphite powder is generally formed by die casting graphite powder and then machining the die cast graphite powder because the graphite has a very high melting point (about 3700 ℃). However, the loose structure of the graphite surface layer causes the graphite particles to fall off, and as the process continues to progress, the size of the transistor is continuously reduced, which means that the particle size is relatively continuously enlarged, and particle contamination may cause rework and even scrapping of the subsequent film, etching and exposure processes (scrub). Therefore, the service life of the graphite component is prolonged, and the generation of micro-dust is reduced, which is necessary for the development of the semiconductor process.

In the prior art, the yield of the process is improved by reducing the above problems of the graphite components: high temperature halogen purification, CVD coating, or chemical synthesis glassy carbon coating, and the like.

The high-temperature halogen purification is to remove loose structures and impurities on the surface of graphite by means of high reactivity of halogen atmosphere at high temperature, and is a high environmental pollution process.

The CVD coating is to deposit a dense carbon film on the surface of the graphite component by using a CVD process, and although the method can effectively cover the loose structure of the graphite surface layer, the process cost is too high, and the CVD coating cannot be applied to the graphite component in large quantity at present.

The chemical synthesis glassy carbon coating is a compact glassy carbon coating formed on the surface of the graphite component by a chemical synthesis process and a high-temperature sintering method. Although the film produced by the method has high compactness and can effectively reduce the falling of surface layer dust, the process cost is high because the process is matched with high-temperature sintering, and the method cannot be widely applied to all graphite components.

In addition, a special coating layer of SiC is required to be introduced into the surface layer of the graphite component, and the compactness of the graphite component is improved by virtue of high physical and chemical resistance of the coating layer so as to improve the process yield. However, the cost of the related components is still very expensive because the plating of SiC passivation layer requires special processing equipment.

In view of this, the utility model system of present case is the research utility model of utmost, and research and development is accomplished the utility model discloses a with low temperature spraying deposit graphite protection coating film on graphite substrate, see through the utility model discloses a method improves its shortcoming in addition to keeping graphite advantage originally, promotes the performance of graphite spare part.

Disclosure of Invention

A primary object of the present invention is to provide a graphite protective layer of graphite assembly, which has the advantages of greatly improving the surface characteristics of the graphite assembly, having excellent adhesion, high hardness, high density, and the like, and inhibiting the generation of particles on the surface of the graphite assembly when in use, thereby improving the yield of the process. Can be applied to any graphite component in the photoelectric and semiconductor industries.

To achieve the above objective, a graphite assembly is provided, which comprises a graphite substrate and at least one graphite film. The graphite film is arranged on the graphite substrate. Wherein the hardness of the graphite film is more than twice of the hardness of the graphite substrate. Wherein, the surface roughness of the graphite film is more than 2 times less than that of the graphite substrate. Wherein the adhesion strength of the graphite film is more than 2 times greater than that of the graphite substrate.

The graphite component is characterized in that the hardness of the graphite thin film is more than twice of the hardness of the graphite substrate.

The graphite assembly is characterized in that the dust emissivity of the graphite film is smaller than that of the graphite substrate.

The graphite assembly is characterized in that the thickness of the graphite film is 5-50 um.

The graphite assembly is characterized in that the graphite film comprises a first graphite film and a second graphite film. The second graphite film has a hardness greater than that of the first graphite film.

The graphite assembly is characterized in that the graphite film comprises a rough surface, and the roughness of the rough surface is 5 nm-10 um. In order to make the aforementioned and other objects, features and advantages of the present invention comprehensible, embodiments accompanied with figures are described in detail below. It is noted that the components in the drawings are merely schematic and are not necessarily to scale.

Drawings

Fig. 1 is a schematic view of a graphite assembly according to a first embodiment of the present invention.

Fig. 2 shows a surface image of a graphite substrate.

Fig. 3 is a surface image of the graphite film.

Fig. 4 is a schematic view of a graphite assembly according to a second embodiment of the present invention.

FIG. 5 is a surface image of a graphite component according to a second embodiment.

Fig. 6 is a schematic view of a graphite assembly according to a third embodiment.

Fig. 7 illustrates a method of manufacturing the graphite assembly of the present invention.

FIG. 8 is a schematic diagram showing a comparison of the concentrations of the particles emitted from the mote.

Detailed Description

To explain technical contents, structural features, and objects and effects of the technical solutions in detail, the following detailed description is given with reference to the accompanying drawings in conjunction with the embodiments.

Referring to fig. 1, fig. 1 is a schematic view illustrating a graphite assembly according to a first embodiment of the present invention. The graphite assembly 100 of the present invention includes a graphite substrate 110 and at least one graphite film 120. The graphite film 120 is disposed on the graphite substrate 110, wherein the hardness of the graphite film 120 is greater than the hardness of the graphite substrate 110. In one embodiment, the hardness of the graphite film 120 is more than twice the hardness of the graphite substrate 110. And the graphite substrate 110 is made of a carbon-based material such as graphite, graphene, etc. In the present embodiment, the graphite substrate 110 is a graphite component used in an ion implanter (ion implanter) ion source of semiconductor processing equipment.

Further, the graphite substrate 110 is pre-treated to have a rough surface, and the pre-treatment is, for example, sand blasting, plasma etching, grinding or laser treatment, and the roughness of the rough surface is 5nm to 10um. The rough surface is the contact surface between the graphite substrate 110 and the graphite thin film 120, and thus the adhesion strength between the graphite substrate 110 and the graphite thin film 120 can be improved. And the adhesion strength of the graphite thin film 120 on the stone substrate 110 after the pretreatment is greater than the adhesion strength of the graphite thin film 120 on the stone substrate 110 before the pretreatment.

The graphite thin film 120 is formed by applying a graphite coating material onto the graphite substrate 110 by means of low-temperature spray (inkjet). In other embodiments, the graphite coating can be applied to the graphite substrate 110 by spin coating, immersion, or the like.

Further, in this embodiment, the graphite coating is prepared by uniformly mixing graphite powder having an average particle size of less than 100nm in a certain weight percentage into the adhesive solution. Then, the graphite coating was uniformly applied on the graphite substrate 110 using a nozzle to form a graphite thin film 120 having a thickness of 400 nm. In another embodiment, the graphite coating can be used to form the graphite film 120 with a thickness of 5-50 um corresponding to different heat treatment methods.

After coating, the graphite substrate 110 and the graphite film 120 are placed in a vacuum or inert gas environment, then the graphite substrate and the graphite film are preheated at a low temperature of below 250 ℃ for more than 180 minutes to volatilize the organic solvent, simultaneously the graphite powder is uniformly arranged into a compact film, and then the graphite powder is subjected to high-temperature heat treatment at a temperature of above 500 ℃ for more than 120 minutes to generate a sintering phenomenon, so that the graphite film 120 with high hardness and low porosity is combined.

In another embodiment, the graphite film 120 of 5-50 um is formed by graphite paint, the graphite substrate 110 and the graphite film 120 are placed in a vacuum or inert gas environment, and then heat treatment is performed at a temperature of 150-500 ℃. And an inert gas, such as nitrogen, argon, helium, or a combination thereof, may be injected during the thermal treatment.

In a preferred embodiment, the porosity of the graphite film of the heat-treated graphite film 120 is less than 15% of the porosity of the graphite substrate 110. The surface roughness of the graphite film 120 should be more than 2 times less than the roughness of the graphite substrate 110. The adhesion strength of the graphite thin film 120 is more than 2 times greater than that of the graphite substrate 110. And the fine dust emissivity (particle emission rate) of the graphite film 120 is smaller than that of the graphite substrate 110.

Referring to fig. 2 and 3, fig. 2 shows a surface image of a graphite substrate, and fig. 3 shows a surface image of a graphite film according to a first embodiment of the present invention, in which a film is formed on the graphite substrate in the above-mentioned manner. Graphite powder with the average grain diameter of less than 100nm is mixed and dispersed in a specific adhesion solution, then a 400nm graphite film is sprayed on an ink base material in a spraying mode, and then the ink base material is baked for 4 to 6 hours at a pre-baking temperature of between 150 and 200 ℃ in a vacuum environment, and is subsequently baked for about 180 minutes in an oven at a baking temperature of 500 ℃. Fig. 2 and 3 are images taken by a Scanning Electron Microscope (SEM). As can be seen from fig. 2, the original graphite substrate 110 has more pores and higher porosity on the surface. As can be seen from fig. 3, after the graphite film 120 is covered, the pores of the graphite film 120 are obviously reduced, and the porosity is obviously reduced. The specific measurement result shows that the surface porosity of the graphite component is reduced to 0.47% from the original 9.61%. The graphite film 120 can also effectively improve the physical properties of the graphite component 100, and the measured hardness of the graphite substrate of the embodiment can be increased from 9.18HV to 25.49HV, which is 278%; the adhesive strength is improved from 9.67MPa to 24.75MPa. The cracking load (cracking load) was lifted from 7.29N to 24.75N.

The utility model discloses in, the average particle size of graphite powder, spraying thick plating, the temperature of baking in advance and time and high temperature thermal treatment's temperature and time all probably influence the physical characteristics of final graphite film. According to the spirit of the utility model, the smaller the average particle size of graphite, the longer the prebaking time, the higher the heat treatment temperature and the thicker the graphite spraying thickness, the lower the porosity of the formed graphite protective film, the higher the hardness and the stronger the adhesion strength.

Referring to fig. 4, fig. 4 is a schematic diagram illustrating a graphite assembly according to a second embodiment of the present invention. In this embodiment, the graphite assembly 200 includes a graphite substrate 210 and a graphite film 220, and the features of the graphite substrate 210 are similar to those of the first embodiment, and therefore are not described herein again. The thickness of the graphite film 220 in the second embodiment is thicker than that in the first embodiment, and the average particle size of the graphite powder, the pre-baking condition and the heat treatment condition are further adjusted. Referring to fig. 5, fig. 5 is a surface image of a graphite component according to a second embodiment. As can be seen from fig. 5, the surface porosity of the graphite film 220 was further reduced to 0.05% by measuring the porosity of the graphite film 220. Furthermore, the graphite hardness is raised to 28.55HV; the adhesive strength is also improved to 25.79MPa.

Referring to fig. 6, fig. 6 is a schematic view of a graphite assembly according to a third embodiment. In the third embodiment, the graphite assembly includes a graphite substrate 310 and at least one graphite film 320, and the features of the graphite substrate 310 are similar to those of the first embodiment, and therefore are not described herein again. The third embodiment is characterized in that the number of the graphite films 320 is plural, and in this embodiment, the number of the graphite films is two. The graphite film 320 includes a first graphite film 320a and a second graphite film 320b, wherein the first graphite film 320a is disposed on the graphite substrate 310, and the second graphite film 320b is disposed on the first graphite film 320 a.

Further, the graphite coating materials of the first graphite film 320a and the second graphite film 320b are prepared by mixing graphite powders with different average particle sizes into the adhesive solution. The graphite coating material of the first graphite thin film 320a is graphite powder having an average particle size of 80 to 150nm, and the graphite coating material of the second graphite thin film 320b is graphite powder having an average particle size of 30 to 80 nm. And the hardness of the second graphite thin film 320b measured after adjusting the preheating condition and the heat treatment condition is greater than that of the first graphite thin film 320 a.

That is, the utility model discloses a graphite subassembly also can cover multilayer graphite film, further uses different particle diameters, different graphite films who follows the solution, and multi-level cover is on graphite substrate, through adjusting graphite subassembly's surface characteristic.

In order to further improve the adhesion between the graphite substrate and the graphite film, the surface of the graphite substrate may be roughened to form a rough surface. The roughness of the rough surface is between 5nm and 10um.

Referring to fig. 7, fig. 7 illustrates a method for manufacturing a graphite assembly according to the present invention. First, in step S10, graphite powder is mixed into a specific adhesive solution to form a graphite coating material. In step S10, nano-grade graphite powder is added to the adhesive solution in a predetermined weight percentage. Wherein the average grain diameter of the graphite powder is less than 100nm.

Then the solution is a volatile organic solvent, such as ethers, ether esters, alcohols, ketones: for example, diethylene Glycol diethyl Ether (Bis (2-ethoxyyethyl) Ether), ethylene Glycol Monobutyl Ether Acetate (Ethylene Glycol monobutylyl Ether Acetate), dipropylene Glycol methyl Ether (Propylene Glycol monomethylether), R-Butyrolactone (R-Butyrolactone), etc. In a preferred embodiment, a Dispersant (Dispersant) can be added to the graphite coating material in step S10 to reduce agglomeration or caking of the graphite powder, and the graphite powder can be uniformly distributed in the subsequent coating step.

In an embodiment, step S11 may be further performed to perform a pretreatment on the graphite substrate 110, so as to form a rough surface on the graphite substrate 110. Wherein the pretreatment is sand blasting, plasma etching, grinding or laser. In step S11, if the pretreatment is sand blasting, the air pressure is 1-10 kg/cm2, and the sand is white alumina with a particle size of 63-89 um. If the pretreatment is plasma etching, the gas power is 180-300W, the gas is oxygen, and the gas flow is 60-100 sccm. Through step S11, a rough surface having a roughness of 5nm to 10um may be formed on the graphite substrate 110.

Next, step S20 is performed to coat the graphite paint on the graphite substrate to form a preliminary graphite film, in which the graphite paint is coated on the graphite substrate by spraying. Then, step S30 is performed to place the graphite film and the graphite substrate in an oxidation-resistant environment, such as a vacuum environment or an environment filled with an inert gas (e.g., nitrogen, argon, helium, etc.), so as to prevent oxidation of the graphite. If the oxidation-resistant environment is vacuum, the vacuum degree is 10 < -3 > to 10 < -5 > torr.

Next, step S40 is performed to perform a low-temperature preheating treatment on the graphite thin film and the graphite substrate, specifically, baking at a temperature of less than 250 ℃ for 180 minutes or longer, where the low-temperature preheating treatment allows the adhesion solution to volatilize, and allows the graphite powder to be uniformly arranged to form a more compact graphite thin film. And step S50, performing heat treatment on the graphite film and the graphite substrate, specifically, performing heat treatment at a temperature of more than or equal to 500 ℃ and less than or equal to 1000 ℃ for more than or equal to 120 minutes, wherein the heat treatment can cause a sintering phenomenon of the graphite powder, so that the graphite powder is sintered into the graphite film with high hardness and low porosity. Therefore, the baking process of steps S40 and S50 can effectively improve the physical properties of the graphite film. In another embodiment, the heat treatment in step S50 may also be performed at a temperature of 150 ℃ or higher and 500 ℃ or lower.

Referring to fig. 8, fig. 8 is a schematic diagram illustrating a comparison of the concentrations of the particles emitted from the motes. In fig. 8, a comparison of the concentration of particles of different sizes emitted by the three graphites, i.e. the degree of emission of the motes, is plotted. It can be seen that the concentration of particles emitted from the conventional graphite substrate is very high, and particularly, particles of 2um or less are very high. While the concentration of particles emitted can be greatly reduced by brushing (wiper cleaning) the graphite substrate, the concentration of particles of 2um or less is still high. The utility model discloses a graphite assembly then has restrained 10um and 20 um's particle concentration, and 2 um's particle concentration also reduces remarkably, so can reduce graphite particle pollution semiconductor assembly's possibility by a wide margin, improves the yield of semiconductor processing procedure.

Compared with the prior solution (such as a glassy carbon coating, high-temperature halogen purification and CVD coating) for preventing the dust on the surface of the graphite from falling off, the graphite component and the graphite film of the utility model have the environmental-friendly and economic film coating, and the high-cost high-temperature sintering process required by the synthesis of the glassy carbon coating is eliminated; and the preparation of the high-density protective film for preventing the micro dust from falling off can be finished without using a high-temperature halogen furnace with high environmental pollution risk for processing.

The above-described embodiments are merely examples for convenience of description and may be modified by persons skilled in the art without departing from the scope of the invention as claimed.

Claims

1. A graphite assembly, comprising:

a graphite substrate; and

at least one graphite film arranged on the graphite substrate;

wherein the hardness of the graphite film is more than twice of that of the graphite substrate;

wherein the porosity of the graphite film is less than 15% of the porosity of the graphite substrate;

wherein, the surface roughness of the graphite film is more than 2 times smaller than that of the graphite substrate;

wherein the adhesion strength of the graphite film is more than 2 times greater than that of the graphite substrate.

2. The graphite assembly of claim 1, wherein the graphite film has a dust emissivity less than a dust emissivity of the graphite substrate.

3. The graphite assembly of claim 1, wherein the graphite film has a thickness of 5to 50um.

4. The graphite assembly of claim 1, wherein the graphite film comprises:

a first graphite film; and

the second graphite film has the hardness greater than that of the first graphite film;

wherein the average grain diameter of the graphite powder used by the second graphite film is smaller than that of the graphite powder used by the first graphite film.

5. The graphite assembly of claim 1 wherein the graphite film comprises a rough surface having a roughness of 5nm to 10um.