CN113025998B - Substrate table for diamond film microwave plasma chemical vapor deposition - Google Patents
Substrate table for diamond film microwave plasma chemical vapor deposition Download PDFInfo
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- CN113025998B CN113025998B CN201911341286.9A CN201911341286A CN113025998B CN 113025998 B CN113025998 B CN 113025998B CN 201911341286 A CN201911341286 A CN 201911341286A CN 113025998 B CN113025998 B CN 113025998B
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- substrate
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- cooling cavity
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- C—CHEMISTRY; METALLURGY
- C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
- C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
- C23C16/00—Chemical coating by decomposition of gaseous compounds, without leaving reaction products of surface material in the coating, i.e. chemical vapour deposition [CVD] processes
- C23C16/44—Chemical coating by decomposition of gaseous compounds, without leaving reaction products of surface material in the coating, i.e. chemical vapour deposition [CVD] processes characterised by the method of coating
- C23C16/458—Chemical coating by decomposition of gaseous compounds, without leaving reaction products of surface material in the coating, i.e. chemical vapour deposition [CVD] processes characterised by the method of coating characterised by the method used for supporting substrates in the reaction chamber
- C23C16/4582—Rigid and flat substrates, e.g. plates or discs
- C23C16/4583—Rigid and flat substrates, e.g. plates or discs the substrate being supported substantially horizontally
- C23C16/4586—Elements in the interior of the support, e.g. electrodes, heating or cooling devices
-
- C—CHEMISTRY; METALLURGY
- C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
- C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
- C23C16/00—Chemical coating by decomposition of gaseous compounds, without leaving reaction products of surface material in the coating, i.e. chemical vapour deposition [CVD] processes
- C23C16/22—Chemical coating by decomposition of gaseous compounds, without leaving reaction products of surface material in the coating, i.e. chemical vapour deposition [CVD] processes characterised by the deposition of inorganic material, other than metallic material
- C23C16/26—Deposition of carbon only
- C23C16/27—Diamond only
- C23C16/274—Diamond only using microwave discharges
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- C—CHEMISTRY; METALLURGY
- C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
- C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
- C23C16/00—Chemical coating by decomposition of gaseous compounds, without leaving reaction products of surface material in the coating, i.e. chemical vapour deposition [CVD] processes
- C23C16/44—Chemical coating by decomposition of gaseous compounds, without leaving reaction products of surface material in the coating, i.e. chemical vapour deposition [CVD] processes characterised by the method of coating
- C23C16/50—Chemical coating by decomposition of gaseous compounds, without leaving reaction products of surface material in the coating, i.e. chemical vapour deposition [CVD] processes characterised by the method of coating using electric discharges
- C23C16/511—Chemical coating by decomposition of gaseous compounds, without leaving reaction products of surface material in the coating, i.e. chemical vapour deposition [CVD] processes characterised by the method of coating using electric discharges using microwave discharges
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- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Chemical Kinetics & Catalysis (AREA)
- General Chemical & Material Sciences (AREA)
- Materials Engineering (AREA)
- Metallurgy (AREA)
- Organic Chemistry (AREA)
- Inorganic Chemistry (AREA)
- Physics & Mathematics (AREA)
- Plasma & Fusion (AREA)
- Chemical Vapour Deposition (AREA)
- Crystals, And After-Treatments Of Crystals (AREA)
Abstract
The invention provides a substrate table combining heat management and magnetic field guided plasma, which is characterized in that materials with different heat conductivities are buried in the substrate table for heat management design to balance the temperatures of different areas of the plasma, so that the temperature gradient in the aspect of substrate temperature level formed when the high-temperature plasma bombards the substrate is reduced. In addition, a magnet is arranged in the substrate table, plasma is guided by a magnetic field, and the shape distribution of the plasma is changed by the buried soft magnetic material, so that the size of the effective area of the substrate temperature and the uniformity of the plasma are further improved. The invention has the advantages of obviously increasing the effective area of film deposition in the diamond microwave plasma chemical vapor deposition process, improving the density distribution of plasma, along with simple device and convenient implementation.
Description
Technical Field
The invention relates to a semiconductor preparation process, in particular to a substrate table in a microwave plasma chemical vapor deposition device of a diamond film.
Background
The diamond film has extremely high electron migration rate, hole migration rate, saturation speed, extremely high breakdown electric field, extremely high heat conductivity, extremely high light transmittance for light rays ranging from vacuum ultraviolet light to far infrared light, good corrosion resistance and small thermal expansion coefficient, and is considered as a third-generation MEMS/NEMS material following silicon. Due to the excellent performance, the diamond material has wide application prospect in the fields of electronics, optics, acoustics, heat, machinery, corrosion resistance, radiation resistance and other industries, military and other high-tech fields, and can bring great influence to human life and great economic benefit.
The diamond film is prepared by high temperature High Pressure (HPHT), hot Filament Chemical Vapor Deposition (HFCVD), plasma Chemical Vapor Deposition (PCVD). Microwave Plasma Chemical Vapor Deposition (MPCVD) has become the method of choice for preparing diamond because of its ability to stably deposit relatively uniform, clean and high quality diamond films. However, the microwave plasma chemical vapor deposition method for preparing the diamond film has certain defects in the process of engineering and industrialization, namely, the deposition rate is low, the deposition area is small, and the uniformity of the deposited film is poor. To make a diamondThe industrial use of stones has become a research focus on how to increase the effective deposition area and uniformity of diamond films. The process of depositing diamond films by microwave plasma chemical vapor deposition generally includes: methane ionization, hydrogen ionization, electron collision existing plasma, namely:wherein is neutral CH 3 Radicals, C 2 H 2 The group is the main growth group of the diamond film, and the H group is the main group for inhibiting the growth of the non-diamond phase. CH (CH) 3 The improvement of the group concentration and the H group concentration has obvious effect on the deposition rate and the quality improvement of the diamond film.
Current methods of generating plasma include capacitive plasma generating frameworks, inductively-excited plasma generating frameworks, electron cyclotron resonance ECR, and frameworks of microwave resonant cavities. The frameworks in which high density plasma is generated are electron cyclotron resonance ECR, and microwave resonance cavity frameworks.
The typical structure of ECR deposition cavity is characterized by that in the upper portion of the cavity a vertical magnetic field greater than 800 Gauss is parallel to the electric field of microwave so as to make the electron cyclotron motion produce resonance, so that it can excite plasma, then it can be transferred onto the deposited substrate slice, and the region of the electron cyclotron resonance deposition cavity in which the plasma is produced is far from the region of substrate. At present, the most common reaction cavity for growing diamond is MPCVD, and the principle of the reaction cavity is that microwaves are input into an approximately cylindrical metal cavity, and the shape and the size of the cylindrical cavity can just generate microwave resonance with the RF frequency of the microwaves, so that a strong electric field is generated above a substrate, and plasma is excited to generate. The microwave resonant cavity is generally used at a frequency of 2.45GHz, and the plasma generated by the method has high density and can generate a large amount of heat to heat the substrate table. Since the electric field distribution of the electric field resonance is a standing wave, the center is high, the amplitude roll-off occurs far from the center, and the radial and axial distributions are very uneven, so that the substrate temperature on the substrate table is distributed in the radial direction and the temperature of the gas above the substrate is not uniform (the radial distribution of the temperature of the gas above the substrate is shown in fig. 1). For the same reason, as shown in fig. 2, the density distribution of the plasma over the substrate also sharply decays in the radial direction. This greatly affects the effective area of MPCVD grown diamond film, and no better method has been proposed to solve this problem in the literature and design.
Disclosure of Invention
In order to overcome the defects in the prior art, the invention provides a substrate table design combining heat conduction and magnetic field guided plasma, which mainly comprises a water cooling cavity, a substrate support (7) and the like, wherein the water cooling cavity is formed by a water cooling cavity wall (1), a cover plate (2) and a sealing ring (3), magnets (17) (18) are arranged in the water cooling cavity, the magnets (17) (18) are arranged in the water cooling cavity (1) and are symmetrically arranged by taking the central axis of the water cooling cavity (1) as the center, the magnets (17) (18) are fixed on the upper plane of the water cooling cavity wall (1) in the water cooling cavity of the water cooling cavity (1) and leave a water flow gap with the cover plate (2) so as to cool and regulate the cover plate (6) to cool a substrate (8), a material annular heat conductor (11) and a circular heat conductor (13) with different thicknesses for regulating heat conduction are arranged between the cover plate (6) and the cover plate (2), the material annular heat conductor (12) and the circular heat conductor (14) for regulating the magnetic field size are arranged on the cover plate (2), and the substrate support (7) is placed in the substrate support (8).
Alternatively, the annular heat conductor (11) and the circular heat conductor (13), and the annular magnetizer (12) and the circular magnetizer (14) may be made of a metal material with copper, aluminum, stainless steel or nickel or a ceramic material of polycrystalline diamond, silicon carbide, aluminum nitride or sapphire.
Preferably, a plurality of annular pits (9) (10) with different depths are arranged at different radiuses at the bottom of the substrate support (7), and a stepped air gap is formed between the substrate support (7) and the adjusting cover plate (6) so as to further finely adjust the temperature and the magnetic field distribution of the substrate (8).
Alternatively, the magnets (17 and 18) are divided into two pieces in the water cooling chamber and are installed in a symmetrical and opposite magnetic poles manner, the magnetic field in the central area forms a horizontal magnetic field, and the magnetic field is gradually changed into a vertical magnetic field in a position far away from the central area, so that the radial diffusion of plasma is pulled.
Alternatively, unlike the previous solution, the magnets (17) (18) combine a ring-shaped magnet, so that the magnetic field in the central region forms a vertical magnetic field, which can act to confine the plasma so that it is relatively uniform in the confinement region, but this solution has the disadvantage of shrinking the effective area of the deposition process.
The invention has the advantages that: by combining the heat conduction and the magnetic field guiding plasma, the homogenization targets of plasma uniformity and temperature uniformity are achieved, and the effective area of MPCVD deposited diamond or graphene is expanded. Meanwhile, due to the guiding of plasma distribution, the plasma can further wrap the surface of the substrate, and the deposition rate is also greatly improved. Provides a way for the practical application of the diamond thin film device technology.
The temperature distribution curve of the substrate and the distribution curve of the electron concentration are simulated by a computer, and the characteristics of high center and radial roll-off are presented. According to the heat-resistant substrate table, the adjusting cover plate and the substrate support are introduced into the substrate table, materials with different heat conductivities are introduced through the design of the adjusting cover plate, the material with higher heat conductivity is introduced into the central area, and the material with smaller heat conductivity is introduced into the area far away from the center, so that the heat resistance of the central area is small and the heat resistance of the edge area is large in the radial different areas. Thus, the non-uniformity of the heating of the substrate by the plasma is suppressed to a certain extent. The substrate is contacted with the substrate table through the substrate support, and the temperature uniformity can be further finely adjusted through the design of air gaps with different thicknesses at the bottom of the substrate support.
Drawings
Fig. 1 is a radial distribution of gas temperature over a typical MPCVD chamber substrate of the prior art.
Fig. 2 is a radial profile of a plasma over a typical MPCVD chamber substrate of the prior art.
FIG. 3 is a schematic view of the structure of an MPCVD substrate table with the magnetic field of the present invention arranged in a horizontal manner.
FIG. 4 is a schematic view of an MPCVD substrate table magnet arrangement with the magnetic field arrangement of the present invention in a horizontal manner.
FIG. 5 is a schematic view of the structure of an MPCVD substrate table with the magnetic field of the present invention arranged in a vertical manner.
FIG. 6 is a schematic diagram of an MPCVD substrate table magnet arrangement with the magnetic field arrangement of the present invention in a vertical manner.
Detailed Description
Embodiments of the present invention are further described below with reference to the accompanying drawings.
Embodiment one: as shown in fig. 3 and 4, the substrate table is designed to be horizontally magnetic. The whole substrate table is a substrate table water-cooling cavity formed by a water-cooling cavity wall 1, a cover plate 2 and a sealing ring 3, and the water-cooling cavity is provided with a water inlet 4 and a water outlet 5. Magnets 17 and 18 are placed in the water-cooled chamber, divided into 2 halves by a ring magnet, and mounted in the water-cooled chamber in a symmetrical, opposite-pole manner, thus forming a horizontal magnet arrangement. The cover plate 2 is overlapped with an adjusting cover plate 6, and heat conduction 11 and magnetic conduction materials 12 with different thicknesses are buried in the adjusting cover plate according to the actual temperature distribution of plasma, so that the temperature distribution of the substrate 8 in the substrate support 7 is uniform. The bottom of the susceptor 7 also has an air gap 9 and 10 design to fine tune the actual temperature distribution.
Embodiment two: as shown in fig. 5 and 6, the substrate table is designed to be a vertical mode magnetic field. The whole substrate table is a substrate table water-cooling cavity formed by a water-cooling cavity wall 1, a cover plate 2 and a sealing ring 3, and the water-cooling cavity is provided with a water inlet 4 and a water outlet 5. Magnets 17 and 18 are placed in the water cooling chamber, and the magnets 17 and 18 are whole circular rings to form magnets in the vertical direction. The cover plate 2 is overlapped with an adjusting cover plate 6, and heat conduction 11 and magnetic conduction materials 12 with different thicknesses are buried in the adjusting cover plate according to the actual temperature distribution of plasma, so that the temperature distribution of the substrate 8 in the substrate support 7 is uniform. The bottom of the susceptor 7 also has an air gap 9 and 10 design to fine tune the actual temperature distribution.
It will be readily appreciated by those skilled in the art that the foregoing description is merely a preferred embodiment of the invention and is not intended to limit the invention, but any modifications, equivalents, improvements or alternatives falling within the spirit and principles of the invention are intended to be included within the scope of the invention.
Claims (1)
1. The substrate table for the diamond film microwave plasma chemical vapor deposition mainly comprises a water cooling cavity and a substrate support (7), wherein the water cooling cavity is composed of a water cooling cavity wall (1), a cover plate (2) and a sealing ring (3), and is characterized in that magnets (17) and (18) are installed in the water cooling cavity and are symmetrically installed around the central axis of the water cooling cavity, the magnets (17) and (18) are fixed on the upper plane of the water cooling cavity wall (1) in the water cooling cavity, a water flow gap is reserved between the magnets and the cover plate (2), the water flow gap is reserved between the magnets and the cover plate (18) so as to facilitate cooling of the substrate (8), an adjusting cover plate (6) is installed on the cover plate (2), annular heat conductors (11) and circular heat conductors (13) with different thicknesses for adjusting heat conduction are installed between the adjusting cover plate (6) and the cover plate (2), annular heat conductors (12) and circular heat conductors (14) with adjustable magnetic field sizes are arranged on the adjusting cover plate (6), the substrate support (7) is used for placing the substrate (8), the annular heat conductors (11) and the circular heat conductors (13) and the annular heat conductors (12) and the circular heat conductors (12) are made of aluminum, silicon carbide or ceramic materials are made of the metal or silicon carbide or ceramic materials, the bottom of the substrate support (7) is provided with a plurality of circular ring pits (9) (10) with different depths, a stepped air gap is formed between the substrate support (7) and the adjusting cover plate (6) so as to further finely adjust the temperature and magnetic field distribution of the substrate (8), the magnets (17) and (18) are divided into two pieces and are arranged in the water cooling cavity and are arranged in a mode of symmetrical positions and opposite magnetic poles, the magnetic fields in the central area form a horizontal magnetic field, the top end surfaces (19) and (20) of the magnets (17) and (18) are flat or inclined surfaces or other shapes, or the magnets (17) and (18) are symmetrically arranged in the water cooling cavity as a ring-shaped integral magnet, the magnetic field in the central area forms a vertical magnetic field, and the top end surfaces (19) and (20) of the magnets (17) and (18) are flat or inclined surfaces or other shapes.
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201911341286.9A CN113025998B (en) | 2019-12-24 | 2019-12-24 | Substrate table for diamond film microwave plasma chemical vapor deposition |
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| Application Number | Priority Date | Filing Date | Title |
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| CN201911341286.9A CN113025998B (en) | 2019-12-24 | 2019-12-24 | Substrate table for diamond film microwave plasma chemical vapor deposition |
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| CN113025998A CN113025998A (en) | 2021-06-25 |
| CN113025998B true CN113025998B (en) | 2023-09-01 |
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| Publication number | Priority date | Publication date | Assignee | Title |
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| CN114016005B (en) * | 2021-10-28 | 2023-10-13 | 河北普莱斯曼金刚石科技有限公司 | Preparation method for co-growing multiple single crystal diamond sheets |
| CN114164418A (en) * | 2021-11-29 | 2022-03-11 | 深圳优普莱等离子体技术有限公司 | Microwave plasma reaction cavity and equipment for chemical vapor deposition |
| CN117660942A (en) * | 2023-12-07 | 2024-03-08 | 合肥先端晶体科技有限责任公司 | Method for reducing surface temperature difference in growth process of large-size diamond |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH06124942A (en) * | 1992-10-12 | 1994-05-06 | Fuji Electric Co Ltd | Manufacture of insulating film |
| CN1451781A (en) * | 2003-05-09 | 2003-10-29 | 华南师范大学 | Device and method for reinforcing organic metal chemical vapor deposition film |
| CN103114278A (en) * | 2013-02-06 | 2013-05-22 | 上海君威新能源装备有限公司 | Planar magnetic control ECR-PECVD (Electron Cyclotron Resonance Plasma-Enhanced Chemical Vapor Deposition) plasma source device |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US8883029B2 (en) * | 2013-02-13 | 2014-11-11 | Lam Research Corporation | Method of making a gas distribution member for a plasma processing chamber |
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- 2019-12-24 CN CN201911341286.9A patent/CN113025998B/en active Active
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH06124942A (en) * | 1992-10-12 | 1994-05-06 | Fuji Electric Co Ltd | Manufacture of insulating film |
| CN1451781A (en) * | 2003-05-09 | 2003-10-29 | 华南师范大学 | Device and method for reinforcing organic metal chemical vapor deposition film |
| CN103114278A (en) * | 2013-02-06 | 2013-05-22 | 上海君威新能源装备有限公司 | Planar magnetic control ECR-PECVD (Electron Cyclotron Resonance Plasma-Enhanced Chemical Vapor Deposition) plasma source device |
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