WO2021117498A1 - Tantalum carbonate-coated graphite member and method for producing same - Google Patents

Tantalum carbonate-coated graphite member and method for producing same Download PDF

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WO2021117498A1
WO2021117498A1 PCT/JP2020/044124 JP2020044124W WO2021117498A1 WO 2021117498 A1 WO2021117498 A1 WO 2021117498A1 JP 2020044124 W JP2020044124 W JP 2020044124W WO 2021117498 A1 WO2021117498 A1 WO 2021117498A1
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film
tantalum carbide
graphite
coated
reactor
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PCT/JP2020/044124
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French (fr)
Japanese (ja)
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狩野　正樹
暁大 平手
山村　和市
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信越化学工業株式会社
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    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B35/00—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products
    • C04B35/515—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products based on non-oxide ceramics
    • C04B35/52—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products based on non-oxide ceramics based on carbon, e.g. graphite
    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B41/00—After-treatment of mortars, concrete, artificial stone or ceramics; Treatment of natural stone
    • C04B41/80—After-treatment of mortars, concrete, artificial stone or ceramics; Treatment of natural stone of only ceramics
    • C04B41/81—Coating or impregnation
    • C04B41/85—Coating or impregnation with inorganic materials
    • C04B41/87—Ceramics
    • 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
    • C23C16/30—Deposition of compounds, mixtures or solid solutions, e.g. borides, carbides, nitrides
    • C23C16/32—Carbides
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L21/00—Processes or apparatus adapted for the manufacture or treatment of semiconductor or solid state devices or of parts thereof
    • H01L21/67—Apparatus specially adapted for handling semiconductor or electric solid state devices during manufacture or treatment thereof; Apparatus specially adapted for handling wafers during manufacture or treatment of semiconductor or electric solid state devices or components ; Apparatus not specifically provided for elsewhere
    • H01L21/683—Apparatus specially adapted for handling semiconductor or electric solid state devices during manufacture or treatment thereof; Apparatus specially adapted for handling wafers during manufacture or treatment of semiconductor or electric solid state devices or components ; Apparatus not specifically provided for elsewhere for supporting or gripping

Definitions

  • the present invention relates to a tantalum carbide-coated graphite member used in a semiconductor manufacturing process or the like and a method for manufacturing the same.
  • the graphite member coated with tantalum carbide has excellent heat resistance and chemical stability, it is used as a heat resistant jig especially in a process in which graphite is severely corroded by a reducing gas or a reactive gas.
  • the applicable range of the graphite member coated with TaC is wide, for example, a wafer tray used in a semiconductor manufacturing process. It is used as a raw material melting crucible, a heating source, a reaction vessel, a heat shield member, a crucible for pulling a single crystal, and the like.
  • Known methods for coating TaC on a graphite substrate include an arc ion plating (AIP) type reactive vapor deposition method, a reactive PVD method, and a chemical vapor deposition method (CVD method).
  • AIP arc ion plating
  • PVD reactive PVD
  • CVD chemical vapor deposition method
  • the TaC coating film obtained by these methods has a problem that the film is likely to be peeled off due to the difference in the coefficient of thermal expansion from that of the graphite base material.
  • the TaC film is a hard and brittle material, there is also a problem that cracks are likely to occur due to thermal stress in the film. For example, when used in a high-temperature reducing gas atmosphere, minute cracks may occur and peeling may occur between the graphite base material and the TaC film in about several tens of hours.
  • Patent Document 1 attempts to delay the progress of cracks by forming the TaC film into a crystal structure in which fine particles are densely laminated.
  • the ratio of the peak intensity I (200) of the (200) plane and the peak intensity I (111) of the (111) plane of the X-ray diffraction of the crystal of the TaC layer is set to I (200) / I.
  • (111) 0.2 to 0.5
  • the tantalum carbide-coated graphite member When the tantalum carbide-coated graphite member is used in a reducing gas atmosphere, if the TaC film is thin, the reducing gas permeates the TaC film and reaches the graphite base material, reduces the graphite, and corrodes the graphite. I will go. In this portion, the TaC film is separated from the graphite base material, and the expansion of such a region causes peeling of the graphite base material and the TaC film.
  • an object of the present invention is to provide a tantalum carbide-coated graphite member that is difficult to peel off when used in a high-temperature reducing atmosphere and a method for producing the same.
  • the tantalum carbide-coated graphite member according to the embodiment of the present invention is a tantalum carbide-coated graphite member in which a graphite base material is coated with a tantalum carbide film, and the graphite base material and tantalum carbide are used. It is characterized in that a thermally decomposed boron nitride film is formed between the film and the film.
  • an intermediate layer is formed between the tantalum carbide film and the pyrolysis boron nitride film.
  • an intermediate layer may be formed between the graphite base material and the thermally decomposed boron nitride film.
  • the film thickness of the tantalum carbide film is preferably 0.5 ⁇ m or more and 100 ⁇ m or less.
  • the bulk density of the graphite base material is preferably 1.6 g / cm 3 or more and 2.0 g / cm 3 or less.
  • the film thickness of the pyrolysis boron nitride film is preferably 10 ⁇ m or more and 1000 ⁇ m or less.
  • the method for producing a tantalum carbide-coated graphite member according to the embodiment of the present invention is a step of forming a pyrolysis boron nitride film on a graphite substrate in a first reactor, a step of forming a pyrolysis boron nitride film.
  • the tantalum carbide-coated graphite member according to any one of the above [1] to [6] is produced by the method for producing the tantalum carbide-coated graphite member.
  • a step of forming a pyrolysis boron nitride film on a graphite base material and a step of forming a pyrolysis boron nitride film are coated.
  • the step of coating the tantalum carbide film on the graphite substrate is continuously performed in the same reactor.
  • the tantalum carbide-coated graphite member according to any one of the above [1] to [6] is produced by the method for producing the tantalum carbide-coated graphite member.
  • the tantalum carbide film after treating the surface roughness Rmax of the thermally decomposed boron nitride film to 10 ⁇ m or more.
  • FIG. 1 It is a flowchart which shows the procedure of the manufacturing method of the tantalum carbide coated graphite member. It is sectional drawing of the wafer tray manufactured using the tantalum carbide coated graphite member. It is a front schematic view of the heater manufactured using the tantalum carbide coated graphite member. It is sectional drawing of the heater manufactured using the tantalum carbide coated graphite member in Example 3. FIG. It is sectional drawing of the wafer tray produced using the tantalum carbide coated graphite member in Example 6.
  • FIG. 1 is a flowchart showing a procedure of a method for manufacturing a tantalum carbide-coated graphite member.
  • a graphite base material is prepared (step S10).
  • the graphite base material is processed into an arbitrary shape according to the application by processing means such as machining. If the graphite material used as the base material has a coefficient of thermal expansion close to the coefficient of thermal expansion in the growth plane direction of the pyrolysis boron nitride (PBN) film to be formed later, the thermal stress between the base material and the film is small. It is preferable because it becomes.
  • Anisotropic graphite having an anisotropic coefficient of thermal expansion may be used, but graphite having a ratio of the maximum value to the minimum value of the coefficient of thermal expansion of 1 or more and 1.5 or less is further used. preferable. It is more preferable to use isotropic graphite.
  • the bulk density of the graphite base material is 1.6 g / cm 3 or more, the strength is increased and it is difficult to break, which is preferable.
  • the production of a graphite base material having a bulk density of more than 2.0 g / cm 3 tends to be expensive due to high technical difficulty, and it is preferably 2.0 g / cm 3 or less in consideration of cost performance. ..
  • a pyrolysis boron nitride (PBN) film is formed on the surface of the graphite substrate (step S20).
  • the method for forming the PBN film is not particularly limited, but for example, it can be formed by reacting ammonia (NH 3 ) and boron trichloride (BCl 3 ) at a high temperature of about 1900 ° C. using a CVD method. ..
  • a CVD method there is an advantage that a PBN film having a uniform thickness can be easily formed according to the complicated shape of the base material, and the film quality can be easily densified and highly purified.
  • the film thickness of the PBN film is 10 ⁇ m or more because the effect of preventing the reducing gas from permeating and reaching the graphite base material is further enhanced, and more preferably 30 ⁇ m or more.
  • the film thickness of the PBN film is 10 ⁇ m or more because the effect of preventing the reducing gas from permeating and reaching the graphite base material is further enhanced, and more preferably 30 ⁇ m or more.
  • it is 1000 ⁇ m or less, delamination in the PBN film due to thermal expansion and peeling at the interface between the base material and the PBN film are less likely to occur, and when it is 500 ⁇ m or less, it is more preferable.
  • the PBN film may be formed directly on the graphite base material, but an intermediate layer may be present between the graphite base material and the PBN film.
  • the material of the intermediate layer include pyrolytic graphite, carbon-added pyrolytic graphite, boron carbide, boron-doped pyrolysis graphite (BPG), and the like.
  • BPG boron-doped pyrolytic graphite
  • a graphite base material is placed in a reactor of a CVD device, evacuated, and heated to about 1600 ° C., while methane gas (CH4) and a small amount of boron trichloride are contained in the reactor. It can be formed by supplying (BCl3) and reacting it.
  • a tantalum carbide (TaC) film is formed on the surface of the PBN film (step S30).
  • the method for forming the TaC film is not particularly limited, but it is preferable to use the CVD method.
  • a compound containing a carbon atom such as methane (CH 4 ) and tantalum halide are heated and vaporized and supplied as a raw material, and TaC is reacted at a high temperature of about 900 ° C. to about 1200 ° C. A film can be formed.
  • the CVD method there is an advantage that a TaC film having a uniform thickness can be easily formed according to the complicated shape of the base material, and the film quality can be easily densified and highly purified.
  • the graphite member after forming the PBN film can be moved in a vacuum from the PBN film forming chamber partitioned by a gate valve or the like to the TaC film forming chamber. It is good to say.
  • This closed system is a space that surrounds the members to prevent the inflow of dirty outside air, and keeps the space clean by creating a vacuum or filling the space with clean gas from which dust particles have been removed. Dripping.
  • the surface of the PBN film Before holding the member in the closed system, the surface of the PBN film may be cleaned by acid cleaning, pure water ultrasonic cleaning, or the like, or a part of the surface of the PBN may be ground to make the surface a clean PBN surface. ..
  • the formation of the PBN film and the formation of the TaC film are performed in the film formation chamber of the same apparatus, the apparatus temperature is changed to the temperature of the TaC film formation following the formation of the PBN film, and the reaction gas to be supplied is replaced with the TaC film.
  • the formation may be performed. In this way, it is not necessary to lower the device temperature to room temperature once, which is advantageous in terms of cost.
  • the TaC film may be formed directly on the PBN film, but an intermediate layer may be provided between the PBN film and the TaC film. This is preferable because the adhesion of the TaC film can be further enhanced.
  • the material of the intermediate layer for example, graphite (C), boron-doped graphite, the material of the intermediate composition of PBN and TaC (B x N x Ta z C) , and the like. If the intermediate layer using the B x N y Ta z C further when the gradient composition gradually changes to TaC rich composition from BN rich composition toward the PBN layer side TaC film side preferred.
  • the intermediate layer it is preferable to prevent metal impurities from being mixed into the interface between the PBN film and the intermediate layer.
  • the gas supplied to the reactor should be switched to the raw material gas for forming the intermediate layer to form the intermediate layer.
  • an inclined layer containing a trace amount (about 1% by weight) of carbon may be provided between the PBN film and the intermediate layer.
  • Such an inclined layer can be formed by forming a PBN film while adding a trace amount of methane (CH4) gas, following the formation of a normal PBN film.
  • the gas supplied to the reactor may be further switched to the TaC raw material gas to form the TaC film.
  • the intermediate layer when employing the B x N y Ta z C graded composition as the material of the intermediate layer, when forming the intermediate layer, by passing both the PBN material gas and TaC raw material gas, PBN on the PBN film A film having an intermediate composition between and TaC may be formed, and the PBN raw material gas may be gradually reduced to shift to TaC film formation using only the TaC raw material gas.
  • the film thickness of the TaC film is preferably 0.5 ⁇ m or more and 100 ⁇ m or less, and more preferably 1 ⁇ m or more and 40 ⁇ m or less. If the TaC film is too thick, the internal thermal stress in the TaC film becomes large, and peeling easily occurs at the interface with the PBN film. Further, since the TaC film has a slow growth rate, increasing the film thickness of the TaC film leads to an increase in cost.
  • the growth rate of the PBN film is relatively fast. Therefore, if the PBN film is made thicker than the TaC film, it is advantageous in terms of cost.
  • the TaC film is preferably formed directly on the surface of the PBN film, but an intervening layer may be present between the PBN film and the TaC film.
  • the tantalum carbide-coated graphite member of the present invention exhibits excellent resistance even in an HCl dry etching process under high temperature in a semiconductor manufacturing apparatus, and is used in a semiconductor manufacturing process such as a wafer tray, a raw material melting crucible, a heating source, and a reaction vessel. It can be preferably applied to members requiring heat resistance and corrosion resistance such as heat shield members and crucibles for pulling single crystals.
  • tantalum carbide-coated graphite member of the present invention can be used in a process that dislikes contamination by boron, such as in a Si semiconductor device manufacturing apparatus.
  • FIG. 2 is a schematic cross-sectional view of a wafer tray 1 manufactured using the tantalum carbide-coated graphite member according to Example 1.
  • the wafer tray 1 in Example 1 was produced by the following procedure. First, isotropic graphite was machined to prepare a 100 mm ⁇ 100 mm ⁇ 10 mm graphite base material 2. As shown in FIG. 2, a recess of ⁇ 76 mm is formed on one end surface of the graphite base material 2, and the corner portion is chamfered in an R shape.
  • the graphite base material 2 was placed in the reactor of the CVD apparatus, and the inside of the reactor was evacuated using a vacuum pump and heated to 1900 ° C. Then, ammonia (NH 3 ) and boron trichloride (BCl 3 ) were supplied into the reactor and reacted to form a pyrolysis boron nitride (PBN) film 3 on the surface of the graphite base material 2.
  • the film thickness of the PBN film 3 was set to 300 ⁇ m.
  • tantalum carbide (TaC) film 4 was formed on the surface of the PBN film 3 by supplying methane (CH 4 ) gas and tantalum chloride (TaCl 5) into the reactor and reacting them.
  • the film thickness of the TaC film 4 was 5 ⁇ m.
  • the inside of the reactor was replaced with N 2 , the temperature was lowered to room temperature, and then the reactor was taken out to complete the wafer tray 1 made of tantalum carbide-coated graphite member. No peeling was observed on this wafer tray 1.
  • a thermal shock test was performed on the produced wafer tray 1.
  • the wafer tray 1 was installed in the evaluation device, and the inside of the device was evacuated. Then, it was rapidly heated to 1500 ° C. in about 3 minutes while flowing ammonia (NH 3 ), and the temperature of 1500 ° C. was maintained for 10 minutes. Subsequently, the rapid ascending / descending temperature cycle of cooling to 200 ° C., heating to 1500 ° C. again, and holding for 10 minutes was repeated. The peeling state of the wafer tray 1 was confirmed every cycle.
  • NH 3 ammonia
  • FIG. 3 is a front schematic view of a heater 5 manufactured by using a tantalum carbide-coated graphite member.
  • the heater 5 was manufactured by the following procedure. First, isotropic graphite was machined to prepare a concentric graphite base material having an outer diameter of ⁇ 300 mm, an inner diameter of ⁇ 250 mm, and a thickness of 10 mm.
  • This graphite substrate was placed in the reactor of the CVD apparatus, and the inside of the reactor was evacuated using a vacuum pump and heated to 1900 ° C. Then, ammonia (NH 3 ) and boron trichloride (BCl 3 ) were supplied into the reactor and reacted to form a pyrolysis boron nitride (PBN) film on the surface of the graphite substrate.
  • the film thickness of this PBN film was 10 ⁇ m.
  • tantalum carbide (TaC) film was formed on the surface of the PBN film by supplying methane (CH 4 ) gas and tantalum chloride (TaCl 5) into the reactor and reacting them.
  • the film thickness of this TaC film was 1 ⁇ m.
  • the produced heater 5 was energized and heated. First, the heater 5 was installed in the evaluation device, and the inside of the device was evacuated. Then, electricity was applied while flowing ammonia (NH 3 ), the mixture was heated to 1500 ° C. in about 30 minutes, and the temperature of 1500 ° C. was maintained for 10 minutes. Subsequently, the rapid ascending / descending temperature cycle of cooling to 200 ° C., heating to 1500 ° C. again and holding for 10 minutes was repeated. The peeling state was confirmed every cycle.
  • NH 3 ammonia
  • FIG. 4 is a schematic cross-sectional view of the heater 5A manufactured by using the tantalum carbide-coated graphite member according to the third embodiment.
  • the heater 5A in Example 3 was produced by the following procedure. First, isotropic graphite was machined to prepare a graphite base material 2A having the same shape as in Example 2.
  • the graphite base material 2A was placed in the reactor of the CVD apparatus, and the inside of the reactor was evacuated using a vacuum pump and heated to 1900 ° C. Then, ammonia (NH 3 ) and boron trichloride (BCl 3 ) were supplied into the reactor and reacted to form a pyrolysis boron nitride (PBN) film 3A on the surface of the graphite base material 2A.
  • the film thickness of the PBN film 3A was set to 50 ⁇ m, and a small amount of methane (CH 4 ) gas was further added to provide an inclined layer 6A having a thickness of about 1 to 2 ⁇ m so that the carbon concentration in the PBN was about 1% by weight.
  • the inside of the reactor was evacuated with the base material 2 on which the PBN film 3A was formed contained in the reactor, and the temperature inside the reactor was set to 1600 ° C. Then, by supplying methane (CH 4 ) gas and a small amount of BCl 3 gas into the reactor and reacting them, a boron-doped graphite film to be an intermediate layer 7A was formed on the surface of the PBN film 3A. The film thickness of this boron-doped graphite film was 2 ⁇ m. The boron concentration in the pyrolytic carbon at this time was 6 to 8% by weight.
  • the inside of the reactor was put into a vacuum state, the temperature inside the reactor was set to 1500 ° C., and heat treatment was performed for 1 hour. Then, by supplying methane (CH 4 ) gas and tantalum chloride (TaCl 5 ) into the reactor and reacting them, a tantalum carbide (TaC) film 4A is formed on the surface of the PBN film 3A with the intermediate layer 7A sandwiched between them. did.
  • the film thickness of the TaC film 4A was set to 5 ⁇ m.
  • the base material 2A was taken out from the reactor to complete the heater 5A of the tantalum carbide-coated graphite member. No peeling was observed in this heater 5A.
  • the produced heater 5A was energized and heated. First, the heater 5A was installed in the evaluation device, and the inside of the device was evacuated. Then, electricity was applied while flowing ammonia (NH 3 ), the mixture was heated to 1500 ° C. in about 30 minutes, and the temperature of 1500 ° C. was maintained for 10 minutes. Subsequently, the rapid ascending / descending temperature cycle of cooling to 200 ° C., heating to 1500 ° C. again, and holding for 10 minutes was repeated. The peeling state was confirmed every cycle.
  • NH 3 ammonia
  • Example 4 First, isotropic graphite was machined to prepare a graphite substrate having the same shape as in Example 2.
  • This graphite substrate was placed in the reactor of the CVD apparatus, and the inside of the reactor was evacuated using a vacuum pump and heated to 1900 ° C. Then, ammonia (NH 3 ) and boron trichloride (BCl 3 ) were supplied into the reactor and reacted to form a pyrolysis boron nitride (PBN) film on the surface of the graphite substrate.
  • the film thickness of this PBN film was 50 ⁇ m.
  • the graphite base material on which the PBN film was formed was once taken out from the reactor, the surface was washed with pure water, and the mixture was placed in a CVD reactor.
  • a clean dry N 2 (dew point ⁇ 75 ° C.) was poured into the anti-container at normal pressure to 1600 ° C. for 30 minutes, and then the inside of the anti-container was evacuated and held for 30 minutes.
  • methane (CH 4 ) gas and tantalum chloride (TaCl 5 ) were supplied to the reactor and reacted to form a tantalum carbide (TaC) film on the surface of the PBN film.
  • the film thickness of this TaC film was 5 ⁇ m.
  • Example 5 First, isotropic graphite was machined to prepare a graphite substrate having the same shape as in Example 2.
  • This graphite substrate was placed in the reactor of the CVD apparatus, and the inside of the reactor was evacuated using a vacuum pump and heated to 1900 ° C. Then, ammonia (NH 3 ) and boron trichloride (BCl 3 ) were supplied into the reactor and reacted to form a pyrolysis boron nitride (PBN) film on the surface of the graphite substrate.
  • the film thickness of this PBN film was 55 ⁇ m.
  • the graphite base material on which the PBN film was formed was once taken out from the reactor, and the surface was ground to obtain a surface roughness Rmax of 12 ⁇ m. After that, the ground surface was washed with aqua regia, then ultrasonically washed with pure water, dried by heating at 120 ° C., and placed in a CVD reactor. The inside of the reactor was evacuated, heated to 120 ° C., and held for 30 minutes. Then, methane (CH 4 ) gas and tantalum chloride (TaCl 5 ) were supplied to the reactor and reacted to form a tantalum carbide (TaC) film on the surface of the PBN film. The film thickness of this TaC film was 5 ⁇ m.
  • the temperature was lowered to room temperature, and then taken out to complete the heater 5 of the tantalum carbide-coated graphite member. No peeling was observed in this heater 5.
  • the produced heater 5 was energized and heated. First, the heater 5 was installed in the evaluation device, and the inside of the device was evacuated. Then, electricity was applied while flowing ammonia (NH 3 ), the mixture was heated to 1500 ° C. in about 30 minutes, and the temperature of 1500 ° C. was maintained for 10 minutes. Subsequently, the rapid ascending / descending temperature cycle of cooling to 200 ° C., heating to 1500 ° C. again, and holding for 10 minutes was repeated. The peeling state was confirmed every cycle.
  • NH 3 ammonia
  • FIG. 5 is a schematic cross-sectional view of a wafer tray 1B manufactured by using the tantalum carbide-coated graphite member according to Example 6.
  • the wafer tray 1B in Example 6 was produced by the following procedure. First, isotropic graphite was machined to prepare a graphite base material 2B of a wafer tray similar to that in Example 1.
  • This graphite base material 2B was placed in the reactor of the CVD apparatus, and the inside of the reactor was evacuated using a vacuum pump and heated to 1600 ° C.
  • a boron-doped pyrolytic graphite (BPG) film is formed as an intermediate layer 7B on the surface of the graphite base material 2B. 2 ⁇ m was formed.
  • the inside of the reactor is heated to 1850 ° C., and ammonia (NH 3 ) and boron trichloride (BCl 3 ) are supplied into the reactor to react, thereby intermediate between BPG.
  • a pyrolysis boron nitride (PBN) film 3B of 75 ⁇ m was formed on the surface of the layer 7B.
  • a small amount of methane gas (CH 4 ) was flowed to further form an intermediate layer 8B of 3 ⁇ m carbon-doped pyrolysis boron nitride (PBCN).
  • tantalum carbide (TaC) film 4B was formed on the surface of the PBN film provided with the intermediate layer 8B.
  • the temperature was lowered to room temperature, and then the reactor was taken out to complete the wafer tray 1B of the tantalum carbide-coated graphite member. No peeling was observed in this wafer tray 1B.
  • a thermal shock test was performed on the produced wafer tray 1B.
  • the wafer tray 1B was installed in the evaluation device, and the inside of the device was evacuated. Then, it was rapidly heated to 1500 ° C. in about 3 minutes while flowing ammonia (NH 3 ), and the temperature of 1500 ° C. was maintained for 10 minutes. Subsequently, the rapid ascending / descending temperature cycle of cooling to 200 ° C., heating to 1500 ° C. again and holding for 10 minutes was repeated. The peeling state of the wafer tray 1B was confirmed every cycle.
  • NH 3 ammonia
  • Isotropic graphite was machined to prepare a 100 mm ⁇ 100 mm ⁇ 10 mm graphite substrate.
  • a recess of ⁇ 76 mm is formed on one end surface of the graphite base material, and the corners are chamfered in an R shape.
  • This graphite substrate was placed in the reactor of the CVD apparatus, the inside of the reactor was evacuated using a vacuum pump, and the mixture was heated to 900 ° C. Then, tantalum carbide (TaC) film was formed on the surface of the PBN film by supplying methane (CH 4 ) gas and tantalum chloride (TaCl 5) into the reactor and reacting them. The film thickness of this TaC film was 5 ⁇ m.
  • a thermal shock test was performed on the produced wafer tray. First, the wafer tray was installed in the evaluation device, and the inside of the device was evacuated. Then, it was rapidly heated to 1500 ° C. in about 3 minutes while flowing ammonia (NH 3 ), and the temperature of 1500 ° C. was maintained for 10 minutes. Subsequently, the rapid ascending / descending temperature cycle of cooling to 200 ° C., heating to 1500 ° C. again, and holding for 10 minutes was repeated. The peeling state was confirmed every cycle.
  • NH 3 ammonia
  • the manufactured wafer tray had cracks at the corners and peeling occurred when the rapid temperature raising / lowering cycle was repeated 50 times.
  • ⁇ Comparative example 2> A wafer tray made of tantalum carbide-coated graphite member was completed in the same manner as in Comparative Example 1. However, in Comparative Example 2, the film thickness of the TaC film was set to 50 ⁇ m.
  • a tantalum carbide-coated graphite member that does not easily peel off the coating film even when used in a high-temperature reducing atmosphere can be obtained. be able to.

Abstract

Provided are a tantalum carbonate-coated graphite member hard to peel in use in a high-temperature reducing atmosphere, and a method for producing same. The tantalum carbonate-coated graphite member according to the present invention comprises a graphite base material coated with a tantalum carbonate film, characterized in that a pyrolytic boron nitride film is formed between the graphite base material and the tantalum carbonate film. The method for producing the tantalum carbonate-coated graphite member is characterized in that a step of coating a graphite base material with a pyrolytic boron nitride film and a step of coating the graphite base material coated with the pyrolytic boron nitride film with a tantalum carbonate film are successively carried out in a single reactor.

Description

炭化タンタル被覆グラファイト部材及びその製造方法Tantalum Carbide Coated Graphite Member and Its Manufacturing Method
　本発明は、半導体製造プロセス等で用いられる炭化タンタル被覆グラファイト部材及びその製造方法に関する。 The present invention relates to a tantalum carbide-coated graphite member used in a semiconductor manufacturing process or the like and a method for manufacturing the same.
　炭化タンタル（ＴａＣ）をコーティングしたグラファイト部材は、耐熱性、化学的安定性に優れるため、特に還元性ガスや反応性ガスによるグラファイトの腐食が激しいプロセスなどに耐熱治具として使用される。 Since the graphite member coated with tantalum carbide (TaC) has excellent heat resistance and chemical stability, it is used as a heat resistant jig especially in a process in which graphite is severely corroded by a reducing gas or a reactive gas.
　また、グラファイト基材を所望の形状に加工することは容易であり、ＴａＣのコーティングプロセスも短時間で済むため、ＴａＣをコーティングしたグラファイト部材の適用範囲は広く、例えば、半導体製造プロセスに用いられるウエハトレー、原料溶融ルツボ、加熱源、反応容器、熱シールド部材、単結晶引上げ用ルツボ等として用いられている。 Further, since it is easy to process the graphite base material into a desired shape and the TaC coating process can be completed in a short time, the applicable range of the graphite member coated with TaC is wide, for example, a wafer tray used in a semiconductor manufacturing process. It is used as a raw material melting crucible, a heating source, a reaction vessel, a heat shield member, a crucible for pulling a single crystal, and the like.
　グラファイト基材にＴａＣをコーティングする方法としては、アークイオンプレーティング（ＡＩＰ）式反応性蒸着法、反応性ＰＶＤ法、化学気層成長法（ＣＶＤ法）などが知られている。しかし、これらの方法で得られたＴａＣのコーティング膜は、グラファイト基材との熱膨張係数の違いから膜の剥離が生じやすいという問題がある。また、ＴａＣ膜は、硬く、脆い材質であるため、膜中の熱応力によりクラックが発生しやすいという問題もある。例えば、高温の還元性ガス雰囲気下で使用すると、微小なクラックが生じ、数十時間程度でグラファイト基材とＴａＣ膜との間に剥離が生じてしまう場合がある。 Known methods for coating TaC on a graphite substrate include an arc ion plating (AIP) type reactive vapor deposition method, a reactive PVD method, and a chemical vapor deposition method (CVD method). However, the TaC coating film obtained by these methods has a problem that the film is likely to be peeled off due to the difference in the coefficient of thermal expansion from that of the graphite base material. Further, since the TaC film is a hard and brittle material, there is also a problem that cracks are likely to occur due to thermal stress in the film. For example, when used in a high-temperature reducing gas atmosphere, minute cracks may occur and peeling may occur between the graphite base material and the TaC film in about several tens of hours.
　そこで、特許文献１では、ＴａＣ膜を微粒子が緻密に積層した結晶組織とすることで、クラックの進行を遅らせることを試みている。 Therefore, Patent Document 1 attempts to delay the progress of cracks by forming the TaC film into a crystal structure in which fine particles are densely laminated.
　また、特許文献２では、ＴａＣ層の結晶のＸ線回折の（２００）面のピーク強度Ｉ（２００）と（１１１）面のピーク強度Ｉ（１１１）との比を、Ｉ（２００）／Ｉ（１１１）＝０．２～０．５、又は、Ｉ（１１１）／Ｉ（２００）＝０．２～０．５とすることで、還元性ガスや反応性ガスと接触したとしても腐食されにくく、クラックや損傷が発生しにくい材料が得られるとしている。 Further, in Patent Document 2, the ratio of the peak intensity I (200) of the (200) plane and the peak intensity I (111) of the (111) plane of the X-ray diffraction of the crystal of the TaC layer is set to I (200) / I. By setting (111) = 0.2 to 0.5 or I (111) / I (200) = 0.2 to 0.5, even if it comes into contact with a reducing gas or a reactive gas, it is corroded. It is said that a material that is difficult to crack and is less likely to be damaged can be obtained.
特開平１０－２３６８９２号公報Japanese Unexamined Patent Publication No. 10-236892 特開２００４－８４０５７号公報Japanese Unexamined Patent Publication No. 2004-84057
　炭化タンタル被覆グラファイト部材を、還元性ガス雰囲気下で使用した場合、ＴａＣ膜が薄いと、還元性ガスがＴａＣ膜を透過してグラファイト基材まで到達し、グラファイトを還元し、グラファイトを腐食していく。この部分ではＴａＣ膜がグラファイト基材から離間した状態となり、このような領域が広がっていくことでグラファイト基材とＴａＣ膜との剥離が生じてしまう。 When the tantalum carbide-coated graphite member is used in a reducing gas atmosphere, if the TaC film is thin, the reducing gas permeates the TaC film and reaches the graphite base material, reduces the graphite, and corrodes the graphite. I will go. In this portion, the TaC film is separated from the graphite base material, and the expansion of such a region causes peeling of the graphite base material and the TaC film.
　一方、ＴａＣ膜を厚くすることで、還元性ガスをグラファイト基材まで到達しにくくすることが可能である。しかしながら、膜厚を厚くすると、ＴａＣ膜におけるグラファイト基材側と表面側との結晶性の違いによって膜中に熱応力が発生し、ＴａＣ膜の部分的な剥離が起こりやすくなることがわかった。 On the other hand, by thickening the TaC film, it is possible to make it difficult for the reducing gas to reach the graphite base material. However, it was found that when the film thickness is increased, thermal stress is generated in the TaC film due to the difference in crystallinity between the graphite base material side and the surface side of the TaC film, and partial peeling of the TaC film is likely to occur.
　したがって、本発明の目的は、高温還元性雰囲気下での使用で剥離しにくい炭化タンタル被覆グラファイト部材とその製造方法を提供することである。 Therefore, an object of the present invention is to provide a tantalum carbide-coated graphite member that is difficult to peel off when used in a high-temperature reducing atmosphere and a method for producing the same.
〔１〕上記の課題を解決すべく、本発明の実施形態に係る炭化タンタル被覆グラファイト部材は、グラファイト基材を炭化タンタル膜で被覆した炭化タンタル被覆グラファイト部材であって、グラファイト基材と炭化タンタル膜との間に、熱分解窒化ホウ素膜が形成されていることを特徴とする。 [1] In order to solve the above problems, the tantalum carbide-coated graphite member according to the embodiment of the present invention is a tantalum carbide-coated graphite member in which a graphite base material is coated with a tantalum carbide film, and the graphite base material and tantalum carbide are used. It is characterized in that a thermally decomposed boron nitride film is formed between the film and the film.
〔２〕本発明では、炭化タンタル膜と、熱分解窒化ホウ素膜との間に中間層が形成されているとよい。 [2] In the present invention, it is preferable that an intermediate layer is formed between the tantalum carbide film and the pyrolysis boron nitride film.
〔３〕本発明では、グラファイト基材と熱分解窒化ホウ素膜との間に中間層が形成されていてもとよい。 [3] In the present invention, an intermediate layer may be formed between the graphite base material and the thermally decomposed boron nitride film.
〔４〕本発明では、炭化タンタル膜の膜厚が、０．５μｍ以上１００μｍ以下であるとよい。 [4] In the present invention, the film thickness of the tantalum carbide film is preferably 0.5 μm or more and 100 μm or less.
〔５〕また、本発明では、グラファイト基材の嵩密度が、１．６ｇ／ｃｍ３以上２．０ｇ／ｃｍ３以下であるとよい。 [5] Further, in the present invention, the bulk density of the graphite base material is preferably 1.6 g / cm 3 or more and 2.0 g / cm 3 or less.
〔６〕また、本発明では、熱分解窒化ホウ素膜の膜厚が、１０μｍ以上１０００μｍ以下であるとよい。 [6] Further, in the present invention, the film thickness of the pyrolysis boron nitride film is preferably 10 μm or more and 1000 μm or less.
〔７〕また、本発明の実施形態に係る炭化タンタル被覆グラファイト部材の製造方法は、第１の反応器内でグラファイト基材上に、熱分解窒化ホウ素膜を形成する工程、熱分解窒化ホウ素膜が被覆されたグラファイト基材を、第２の反応器内で、不活性ガス雰囲気もしくは真空下の閉鎖系に保持する工程、第２の反応器内で、熱分解窒化ホウ素膜が被覆されたグラファイト基材上に、炭化タンタル膜を被覆する工程、を備えることを特徴とする。そして、この炭化タンタル被覆グラファイト部材の製造方法により、上記〔１〕から〔６〕の何れかに記載の炭化タンタル被覆グラファイト部材が製造される。 [7] Further, the method for producing a tantalum carbide-coated graphite member according to the embodiment of the present invention is a step of forming a pyrolysis boron nitride film on a graphite substrate in a first reactor, a step of forming a pyrolysis boron nitride film. The step of holding the graphite base material coated with the above in an inert gas atmosphere or a closed system under vacuum in the second reactor, graphite coated with a pyrolysis boron nitride film in the second reactor. It is characterized by comprising a step of coating a tantalum carbide film on a base material. Then, the tantalum carbide-coated graphite member according to any one of the above [1] to [6] is produced by the method for producing the tantalum carbide-coated graphite member.
〔８〕また、本発明の他の実施形態に係る炭化タンタル被覆グラファイト部材の製造方法は、グラファイト基材上に、熱分解窒化ホウ素膜を形成する工程と、熱分解窒化ホウ素膜が被覆されたグラファイト基材上に、炭化タンタル膜を被覆する工程が、同一の反応器内で連続的になされることを特徴とする。そして、この炭化タンタル被覆グラファイト部材の製造方法により、上記〔１〕から〔６〕の何れかに記載の炭化タンタル被覆グラファイト部材が製造される。 [8] Further, in the method for producing a tantalum carbide-coated graphite member according to another embodiment of the present invention, a step of forming a pyrolysis boron nitride film on a graphite base material and a step of forming a pyrolysis boron nitride film are coated. The step of coating the tantalum carbide film on the graphite substrate is continuously performed in the same reactor. Then, the tantalum carbide-coated graphite member according to any one of the above [1] to [6] is produced by the method for producing the tantalum carbide-coated graphite member.
〔９〕本発明では、熱分解窒化ホウ素膜を形成する工程と炭化タンタル膜を被覆する工程との間に、熱分解窒化ホウ素膜の表面を酸洗浄する工程を有するとよい。 [9] In the present invention, it is preferable to have a step of pickling the surface of the pyrolysis boron nitride film between the step of forming the pyrolysis boron nitride film and the step of coating the tantalum carbide film.
〔１０〕本発明では、熱分解窒化ホウ素膜の表面粗さＲｍａｘを１０μｍ以上に処理した後に炭化タンタル膜を形成するとよい。 [10] In the present invention, it is preferable to form the tantalum carbide film after treating the surface roughness Rmax of the thermally decomposed boron nitride film to 10 μm or more.
　本発明によれば、高温還元性雰囲気下で使用しても、被覆膜の剥離が生じにくい炭化タンタル被覆グラファイト部材を得ることができる。 According to the present invention, it is possible to obtain a tantalum carbide-coated graphite member in which peeling of the coating film is unlikely to occur even when used in a high-temperature reducing atmosphere.
炭化タンタル被覆グラファイト部材の製造方法の手順を示すフローチャートである。It is a flowchart which shows the procedure of the manufacturing method of the tantalum carbide coated graphite member. 炭化タンタル被覆グラファイト部材を用いて作製したウエハトレーの断面概略図である。It is sectional drawing of the wafer tray manufactured using the tantalum carbide coated graphite member. 炭化タンタル被覆グラファイト部材を用いて作製したヒータの正面概略図である。It is a front schematic view of the heater manufactured using the tantalum carbide coated graphite member. 実施例３における炭化タンタル被覆グラファイト部材を用いて作製されたヒータの断面概略図である。It is sectional drawing of the heater manufactured using the tantalum carbide coated graphite member in Example 3. FIG. 実施例６における炭化タンタル被覆グラファイト部材を用いて作製されたウエハトレーの断面概略図である。It is sectional drawing of the wafer tray produced using the tantalum carbide coated graphite member in Example 6.
　以下、本発明の実施形態について詳細に説明するが、本発明は、これらに限定されるものではない。 Hereinafter, embodiments of the present invention will be described in detail, but the present invention is not limited thereto.
　はじめに、図１を参照して、本発明の実施形態に係る炭化タンタル被覆グラファイト部材の製造方法を説明する。図１は、炭化タンタル被覆グラファイト部材の製造方法の手順を示すフローチャートである。 First, a method for manufacturing a tantalum carbide-coated graphite member according to an embodiment of the present invention will be described with reference to FIG. FIG. 1 is a flowchart showing a procedure of a method for manufacturing a tantalum carbide-coated graphite member.
　当該製造方法では、まず、グラファイト基材を準備する（ステップＳ１０）。グラファイト基材は、機械加工等の加工手段によって、用途に応じた任意形状に加工されている。基材として用いるグラファイト材料は、後に形成する熱分解窒化ホウ素（ＰＢＮ）膜の成長面方向の熱膨張率と近い熱膨張率のものを用いると、基材と膜との間の熱応力が小さくなるので好ましい。また、熱膨張率に異方性がある異方性黒鉛を用いても構わないが、その熱膨張率の最大値と最小値のとの比が１以上１．５以下の黒鉛を用いると更に好ましい。等方性黒鉛を用いると更に好ましい。 In the manufacturing method, first, a graphite base material is prepared (step S10). The graphite base material is processed into an arbitrary shape according to the application by processing means such as machining. If the graphite material used as the base material has a coefficient of thermal expansion close to the coefficient of thermal expansion in the growth plane direction of the pyrolysis boron nitride (PBN) film to be formed later, the thermal stress between the base material and the film is small. It is preferable because it becomes. Anisotropic graphite having an anisotropic coefficient of thermal expansion may be used, but graphite having a ratio of the maximum value to the minimum value of the coefficient of thermal expansion of 1 or more and 1.5 or less is further used. preferable. It is more preferable to use isotropic graphite.
　また、グラファイト基材の嵩密度を１．６ｇ／ｃｍ３以上にすると、強度が高まり壊れにくくなるので好ましい。しかしながら、嵩密度が２．０ｇ／ｃｍ３を超えるグラファイト基材の作製は技術的難度が高いので高額になりがちであり、コストパフォーマンスを考慮して２．０ｇ／ｃｍ３以下とするのが好ましい。 Further, when the bulk density of the graphite base material is 1.6 g / cm 3 or more, the strength is increased and it is difficult to break, which is preferable. However, the production of a graphite base material having a bulk density of more than 2.0 g / cm 3 tends to be expensive due to high technical difficulty, and it is preferably 2.0 g / cm 3 or less in consideration of cost performance. ..
　次に、グラファイト基材表面に熱分解窒化ホウ素（ＰＢＮ）膜を形成する（ステップＳ２０）。ＰＢＮ膜の形成方法は特に限定されないが、例えば、ＣＶＤ法を用いてアンモニア（ＮＨ３）と三塩化ホウ素（ＢＣｌ３ ）とを、約１９００℃の高温下で反応させることによって形成することができる。ＣＶＤ法を用いると、基材の複雑形状に合わせて均一な厚みのＰＢＮ膜を形成し易く、また膜質の緻密化や高純度化をし易くなる利点がある。 Next, a pyrolysis boron nitride (PBN) film is formed on the surface of the graphite substrate (step S20). The method for forming the PBN film is not particularly limited, but for example, it can be formed by reacting ammonia (NH 3 ) and boron trichloride (BCl 3 ) at a high temperature of about 1900 ° C. using a CVD method. .. When the CVD method is used, there is an advantage that a PBN film having a uniform thickness can be easily formed according to the complicated shape of the base material, and the film quality can be easily densified and highly purified.
　このとき、ＰＢＮ膜の膜厚を、１０μｍ以上にすると還元性ガスが透過してグラファイト基材に到達するのを防ぐ効果が更に高まるので好ましく、３０μｍ以上にするとさらに好ましい。一方、１０００μｍ以下にすると、熱膨張によるＰＢＮ膜内での層間剥離や基材とＰＢＮ膜界面での剥離が起こりにくくなり好ましく、５００μｍ以下にすると更に好ましい。 At this time, it is preferable that the film thickness of the PBN film is 10 μm or more because the effect of preventing the reducing gas from permeating and reaching the graphite base material is further enhanced, and more preferably 30 μm or more. On the other hand, when it is 1000 μm or less, delamination in the PBN film due to thermal expansion and peeling at the interface between the base material and the PBN film are less likely to occur, and when it is 500 μm or less, it is more preferable.
　ＰＢＮ膜は、グラファイト基材に直接形成されていてもよいが、グラファイト基材とＰＢＮ膜との間に中間層が存在していてもよい。中間層の材質としては、例えばパイロリティックグラファイト、炭素添加パイロリティックグラファイト、炭化ホウ素、ボロンドープ熱分解グラファイト（ＢＰＧ）などが挙げられる。ボロンドープ熱分解グラファイト（ＢＰＧ）膜は、グラファイト基材をＣＶＤ装置の反応器内に入れて、真空引きし、１６００℃程度に加熱しながら、反応器内にメタンガス（ＣＨ４）と微量の三塩化ホウ素（ＢＣｌ３）を供給して反応させることによって形成することができる。 The PBN film may be formed directly on the graphite base material, but an intermediate layer may be present between the graphite base material and the PBN film. Examples of the material of the intermediate layer include pyrolytic graphite, carbon-added pyrolytic graphite, boron carbide, boron-doped pyrolysis graphite (BPG), and the like. In the boron-doped pyrolytic graphite (BPG) film, a graphite base material is placed in a reactor of a CVD device, evacuated, and heated to about 1600 ° C., while methane gas (CH4) and a small amount of boron trichloride are contained in the reactor. It can be formed by supplying (BCl3) and reacting it.
　続いて、ＰＢＮ膜の表面に炭化タンタル（ＴａＣ）膜を形成する（ステップＳ３０）。ＴａＣ膜の形成方法は特に限定されないが、ＣＶＤ法を用いることが好ましい。ＣＶＤ法では、例えば、メタン（ＣＨ４）のような炭素原子を含む化合物とハロゲン化タンタルとを加熱気化させて原料として供給し、約９００℃から約１２００℃の高温下で反応させることによってＴａＣ膜を形成することができる。ＣＶＤ法を用いると、基材の複雑形状に合わせて均一な厚みのＴａＣ膜を形成し易く、また膜質の緻密化や高純度化をし易くなる利点がある。 Subsequently, a tantalum carbide (TaC) film is formed on the surface of the PBN film (step S30). The method for forming the TaC film is not particularly limited, but it is preferable to use the CVD method. In the CVD method, for example, a compound containing a carbon atom such as methane (CH 4 ) and tantalum halide are heated and vaporized and supplied as a raw material, and TaC is reacted at a high temperature of about 900 ° C. to about 1200 ° C. A film can be formed. When the CVD method is used, there is an advantage that a TaC film having a uniform thickness can be easily formed according to the complicated shape of the base material, and the film quality can be easily densified and highly purified.
　ここで、ＰＢＮ膜が劣化しにくくすべく、ＰＢＮ膜とＴａＣ膜との界面への金属不純物の混入を防ぐことが好ましい。金属不純物の混入を防ぐためには、例えば、ＰＢＮ膜を成膜した後のグラファイト部材を、ゲートバルブ等で仕切られたＰＢＮ成膜室からＴａＣ膜成膜用の成膜室へ真空中で移動可能とするとよい。あるいは、成膜室で閉鎖系に保持してＰＢＮ膜の表面を清浄に保った状態でＴａＣ膜の形成に移行するとよい。この閉鎖系とは、部材を包囲して汚れた外気が流入しないようにした空間であり、その空間を真空状態にしたりゴミ粒子を除去した清浄なガスで満たしたりすることで清浄な状態が保たれる。 Here, in order to prevent the PBN film from deteriorating, it is preferable to prevent metal impurities from being mixed into the interface between the PBN film and the TaC film. In order to prevent the mixing of metal impurities, for example, the graphite member after forming the PBN film can be moved in a vacuum from the PBN film forming chamber partitioned by a gate valve or the like to the TaC film forming chamber. It is good to say. Alternatively, it is preferable to shift to the formation of the TaC film in a state where the surface of the PBN film is kept clean by holding it in a closed system in the film forming chamber. This closed system is a space that surrounds the members to prevent the inflow of dirty outside air, and keeps the space clean by creating a vacuum or filling the space with clean gas from which dust particles have been removed. Dripping.
　部材を閉鎖系に保持する前にＰＢＮ膜の表面を酸洗浄や純水超音波洗浄などで洗浄したり、ＰＢＮの表面の一部を研削したりして、表面を清浄なＰＢＮ面としてもよい。 Before holding the member in the closed system, the surface of the PBN film may be cleaned by acid cleaning, pure water ultrasonic cleaning, or the like, or a part of the surface of the PBN may be ground to make the surface a clean PBN surface. ..
　また、ＰＢＮ膜の形成とＴａＣ膜の形成を同一装置の成膜室内で行うこととし、ＰＢＮ膜形成に引き続いて装置温度をＴａＣ膜形成の温度に変更し、供給する反応ガスを入れ替えてＴａＣ膜形成を行ってもよい。このようにすれば、装置温度を一旦室温まで下げる必要もなくなるのでコスト的にも有利となる。 Further, the formation of the PBN film and the formation of the TaC film are performed in the film formation chamber of the same apparatus, the apparatus temperature is changed to the temperature of the TaC film formation following the formation of the PBN film, and the reaction gas to be supplied is replaced with the TaC film. The formation may be performed. In this way, it is not necessary to lower the device temperature to room temperature once, which is advantageous in terms of cost.
　ＴａＣ膜は、ＰＢＮ膜の上に直接形成されていてもよいが、ＰＢＮ膜とＴａＣ膜との間に中間層を設けてもよい。こうすると、ＴａＣ膜の密着性を更に高めることができるため好ましい。中間層の材質は、例えばグラファイト（Ｃ）、ボロンドープグラファイト、ＰＢＮとＴａＣの中間組成の材質（ＢｘＮｘＴａｚＣ）などが挙げられる。中間層にＢｘＮｙＴａｚＣを用いる場合は、ＰＢＮ膜側からＴａＣ膜側に向かってＢＮリッチな組成からＴａＣリッチな組成へと徐々に変化する傾斜組成にすると更に好ましい。 The TaC film may be formed directly on the PBN film, but an intermediate layer may be provided between the PBN film and the TaC film. This is preferable because the adhesion of the TaC film can be further enhanced. The material of the intermediate layer, for example, graphite (C), boron-doped graphite, the material of the intermediate composition of PBN and TaC (B x N x Ta z C) , and the like. If the intermediate layer using the B x N y Ta z C further when the gradient composition gradually changes to TaC rich composition from BN rich composition toward the PBN layer side TaC film side preferred.
　中間層を形成する際には、ＰＢＮ膜と中間層との界面への金属不純物の混入を防ぐことが好ましい。ＰＢＮ膜と中間層との界面への金属不純物の混入を防ぐためにはＰＢＮ膜の形成に引き続いて、反応器に供給するガスを中間層形成用の原料ガスに切り替えて中間層を形成するのが好ましい。また、ＰＢＮ膜と中間層の間に、ＰＢＮ中に微量（１重量％程度）の炭素を含む傾斜層を設けてもよい。このような傾斜層は通常のＰＢＮ膜の形成に続けて、微量のメタン（ＣＨ４）ガスを添加しながらのＰＢＮ膜形成を行うことで形成することができる。 When forming the intermediate layer, it is preferable to prevent metal impurities from being mixed into the interface between the PBN film and the intermediate layer. In order to prevent metal impurities from entering the interface between the PBN film and the intermediate layer, following the formation of the PBN film, the gas supplied to the reactor should be switched to the raw material gas for forming the intermediate layer to form the intermediate layer. preferable. Further, an inclined layer containing a trace amount (about 1% by weight) of carbon may be provided between the PBN film and the intermediate layer. Such an inclined layer can be formed by forming a PBN film while adding a trace amount of methane (CH4) gas, following the formation of a normal PBN film.
　また、中間層を形成した後、更に、反応器に供給するガスをＴａＣ原料ガスに切り替えて、ＴａＣ膜を形成してもよい。 Further, after forming the intermediate layer, the gas supplied to the reactor may be further switched to the TaC raw material gas to form the TaC film.
　中間層の材質として傾斜組成のＢｘＮｙＴａｚＣを採用する場合には、中間層を形成するときに、ＰＢＮ原料ガスとＴａＣ原料ガスの両方を流すことにより、ＰＢＮ膜の上にＰＢＮとＴａＣの中間組成の膜を形成し、徐々にＰＢＮ原料ガスを低減してＴａＣ原料ガスのみとしてＴａＣ膜形成に移行してもよい。 When employing the B x N y Ta z C graded composition as the material of the intermediate layer, when forming the intermediate layer, by passing both the PBN material gas and TaC raw material gas, PBN on the PBN film A film having an intermediate composition between and TaC may be formed, and the PBN raw material gas may be gradually reduced to shift to TaC film formation using only the TaC raw material gas.
　ＴａＣ膜の膜厚は、０．５μｍ以上１００μｍ以下であることが好ましく、１μｍ以上４０μｍ以下であることがさらに好ましい。ＴａＣ膜が厚すぎると、ＴａＣ膜内の内部熱応力が大きくなりＰＢＮ膜との界面で剥離が起こりやすくなる。また、ＴａＣ膜は成長速度が遅いため、ＴａＣ膜の膜厚を厚くすることはコストアップにつながる。 The film thickness of the TaC film is preferably 0.5 μm or more and 100 μm or less, and more preferably 1 μm or more and 40 μm or less. If the TaC film is too thick, the internal thermal stress in the TaC film becomes large, and peeling easily occurs at the interface with the PBN film. Further, since the TaC film has a slow growth rate, increasing the film thickness of the TaC film leads to an increase in cost.
　一方、ＰＢＮ膜の成長速度は比較的速い。このため、ＰＢＮ膜をＴａＣ膜よりも厚くすれば、コスト面でも有利となる。 On the other hand, the growth rate of the PBN film is relatively fast. Therefore, if the PBN film is made thicker than the TaC film, it is advantageous in terms of cost.
　ＴａＣ膜は、ＰＢＮ膜表面に直接形成されていることが好ましいが、ＰＢＮ膜とＴａＣ膜との間に介在層が存在していても構わない。 The TaC film is preferably formed directly on the surface of the PBN film, but an intervening layer may be present between the PBN film and the TaC film.
　このような炭化タンタル被覆グラファイト部材であれば、ＴａＣ膜の厚みを膜中の熱応力が問題にならない程度に薄くしたとしても、ＴａＣ膜を透過した還元性ガスがグラファイト基材まで到達することを、還元性ガスに対して耐食性のあるＰＢＮ膜によって防ぐことができる。 With such a tantalum carbide-coated graphite member, even if the thickness of the TaC film is reduced to such an extent that the thermal stress in the film does not become a problem, the reducing gas that has passed through the TaC film reaches the graphite substrate. , Can be prevented by a PBN membrane that is corrosion resistant to reducing gases.
　本発明の炭化タンタル被覆グラファイト部材は、半導体製造装置内での高温下のＨＣｌドライエッチングプロセスなどにおいても優れた耐性を発揮し、半導体製造プロセスに用いられるウエハトレー、原料溶融ルツボ、加熱源、反応容器、熱シールド部材、単結晶引上げ用ルツボ等の耐熱性、耐食性を要する部材に好ましく適用することができる。 The tantalum carbide-coated graphite member of the present invention exhibits excellent resistance even in an HCl dry etching process under high temperature in a semiconductor manufacturing apparatus, and is used in a semiconductor manufacturing process such as a wafer tray, a raw material melting crucible, a heating source, and a reaction vessel. It can be preferably applied to members requiring heat resistance and corrosion resistance such as heat shield members and crucibles for pulling single crystals.
　また、本発明の炭化タンタル被覆グラファイト部材は、Ｓｉ半導体デバイス製造装置内のようなホウ素による汚染を嫌うようなプロセスでも使用することができる。 Further, the tantalum carbide-coated graphite member of the present invention can be used in a process that dislikes contamination by boron, such as in a Si semiconductor device manufacturing apparatus.
〈実施例１〉
　図２は、実施例１における炭化タンタル被覆グラファイト部材を用いて作製されたウエハトレー１の断面概略図である。実施例１におけるウエハトレー１は、以下の手順で作製された。はじめに、等方性グラファイトを機械加工して、１００ｍｍ×１００ｍｍ×１０ｍｍのグラファイト基材２を準備した。図２に示されるように、グラファイト基材２の一端面にはφ７６ｍｍの凹部が形成されており、角部はＲ形状に面取りが施されている。 <Example 1>
FIG. 2 is a schematic cross-sectional view of a wafer tray 1 manufactured using the tantalum carbide-coated graphite member according to Example 1. The wafer tray 1 in Example 1 was produced by the following procedure. First, isotropic graphite was machined to prepare a 100 mm × 100 mm × 10 mm graphite base material 2. As shown in FIG. 2, a recess of φ76 mm is formed on one end surface of the graphite base material 2, and the corner portion is chamfered in an R shape.
　このグラファイト基材２をＣＶＤ装置の反応器内に入れて、真空ポンプを用いて反応器内を真空状態にし、１９００℃まで加熱した。その後、反応器内にアンモニア（ＮＨ３）と三塩化ホウ素（ＢＣｌ３ ）を供給して反応させることによって、グラファイト基材２の表面上に熱分解窒化ホウ素（ＰＢＮ）膜３を形成した。このＰＢＮ膜３の膜厚は３００μｍとした。 The graphite base material 2 was placed in the reactor of the CVD apparatus, and the inside of the reactor was evacuated using a vacuum pump and heated to 1900 ° C. Then, ammonia (NH 3 ) and boron trichloride (BCl 3 ) were supplied into the reactor and reacted to form a pyrolysis boron nitride (PBN) film 3 on the surface of the graphite base material 2. The film thickness of the PBN film 3 was set to 300 μm.
　続いて、ＰＢＮ膜３が成膜された基材２を反応器に収めたままの状態で、反応器内を窒素（Ｎ２）で置換した後で真空状態にし、反応器内の温度を９００℃にした。その後、反応器内にメタン（ＣＨ４）ガスと塩化タンタル（ＴａＣｌ５）を供給して反応させることによって、ＰＢＮ膜３の表面上に炭化タンタル（ＴａＣ）膜４を形成した。このＴａＣ膜４の膜厚は５μｍとした。 Subsequently, while the base material 2 on which the PBN film 3 was formed was still contained in the reactor, the inside of the reactor was replaced with nitrogen (N 2 ) and then a vacuum state was created, and the temperature inside the reactor was set to 900. It was set to ℃. Then, tantalum carbide (TaC) film 4 was formed on the surface of the PBN film 3 by supplying methane (CH 4 ) gas and tantalum chloride (TaCl 5) into the reactor and reacting them. The film thickness of the TaC film 4 was 5 μm.
　反応器内をＮ２で置換した後、常温まで降温した後、取り出して、炭化タンタル被覆グラファイト部材のウエハトレー１を完成させた。このウエハトレー１に剥離は見られなかった。 The inside of the reactor was replaced with N 2 , the temperature was lowered to room temperature, and then the reactor was taken out to complete the wafer tray 1 made of tantalum carbide-coated graphite member. No peeling was observed on this wafer tray 1.
　作製したウエハトレー１について熱衝撃試験を行った。まず、ウエハトレー１を評価用装置内に設置し、装置内を真空排気した。その後、アンモニア（ＮＨ３）を流しながら約３分間で１５００℃まで急速加熱して、１５００℃の温度を１０分間保持した。続いて、２００℃まで冷却し、再び１５００℃まで加熱昇温して１０分間保持する急速昇降温サイクルを繰り返した。サイクル毎にウエハトレー１における剥離状態を確認した。 A thermal shock test was performed on the produced wafer tray 1. First, the wafer tray 1 was installed in the evaluation device, and the inside of the device was evacuated. Then, it was rapidly heated to 1500 ° C. in about 3 minutes while flowing ammonia (NH 3 ), and the temperature of 1500 ° C. was maintained for 10 minutes. Subsequently, the rapid ascending / descending temperature cycle of cooling to 200 ° C., heating to 1500 ° C. again, and holding for 10 minutes was repeated. The peeling state of the wafer tray 1 was confirmed every cycle.
　作製したウエハトレー１は、急速昇降温サイクルを１００回繰り返した時点でも剥離や腐食は観察されなかった。 No peeling or corrosion was observed in the produced wafer tray 1 even when the rapid elevating temperature cycle was repeated 100 times.
〈実施例２〉
　図３は、炭化タンタル被覆グラファイト部材を用いて作製されたヒータ５の正面概略図である。ヒータ５は、以下の手順で作製された。はじめに、等方性グラファイトを機械加工して、外径φ３００ｍｍ×内径φ２５０ｍｍ、厚さ１０ｍｍの同心円形状で折り返しのあるグラファイト基材を準備した。 <Example 2>
FIG. 3 is a front schematic view of a heater 5 manufactured by using a tantalum carbide-coated graphite member. The heater 5 was manufactured by the following procedure. First, isotropic graphite was machined to prepare a concentric graphite base material having an outer diameter of φ300 mm, an inner diameter of φ250 mm, and a thickness of 10 mm.
　このグラファイト基材をＣＶＤ装置の反応器内に入れて、真空ポンプを用いて反応器内を真空状態にし、１９００℃まで加熱した。その後、反応器内にアンモニア（ＮＨ３）と三塩化ホウ素（ＢＣｌ３ ）を供給して反応させることによって、グラファイト基材の表面上に熱分解窒化ホウ素（ＰＢＮ）膜を形成した。このＰＢＮ膜の膜厚は１０μｍとした。 This graphite substrate was placed in the reactor of the CVD apparatus, and the inside of the reactor was evacuated using a vacuum pump and heated to 1900 ° C. Then, ammonia (NH 3 ) and boron trichloride (BCl 3 ) were supplied into the reactor and reacted to form a pyrolysis boron nitride (PBN) film on the surface of the graphite substrate. The film thickness of this PBN film was 10 μm.
　続いて、ＰＢＮ成膜された基材を反応器に収めたままの状態で、反応器内を真空状態にし、反応器内の温度を９００℃にした。その後、反応器内にメタン（ＣＨ４）ガスと塩化タンタル（ＴａＣｌ５）を供給して反応させることによって、ＰＢＮ膜の表面上に炭化タンタル（ＴａＣ）膜を形成した。このＴａＣ膜の膜厚は１μｍとした。 Subsequently, the inside of the reactor was evacuated while the base material on which the PBN film was formed was still contained in the reactor, and the temperature inside the reactor was set to 900 ° C. Then, tantalum carbide (TaC) film was formed on the surface of the PBN film by supplying methane (CH 4 ) gas and tantalum chloride (TaCl 5) into the reactor and reacting them. The film thickness of this TaC film was 1 μm.
　反応器内をＮ２で置換した後、常温まで降温した後、取り出して、炭化タンタル被覆グラファイト部材のヒータ５を完成させた。このヒータ５に剥離は見られなかった。 After replacing the inside of the reactor with N 2 , the temperature was lowered to room temperature, and then the reactor was taken out to complete the heater 5 of the tantalum carbide-coated graphite member. No peeling was observed in this heater 5.
　作製したヒータ５について通電加熱を行った。まず、ヒータ５を評価用装置内に設置し、装置内を真空排気した。その後、アンモニア（ＮＨ３）を流しながら通電し約３０分間で１５００℃まで加熱して、１５００℃の温度を１０分間保持した。続いて、２００℃まで冷却し、再び１５００℃まで加熱昇温して１０分間保持する急速昇降温サイクルを繰り返した。サイクル毎に剥離状態を確認した。 The produced heater 5 was energized and heated. First, the heater 5 was installed in the evaluation device, and the inside of the device was evacuated. Then, electricity was applied while flowing ammonia (NH 3 ), the mixture was heated to 1500 ° C. in about 30 minutes, and the temperature of 1500 ° C. was maintained for 10 minutes. Subsequently, the rapid ascending / descending temperature cycle of cooling to 200 ° C., heating to 1500 ° C. again and holding for 10 minutes was repeated. The peeling state was confirmed every cycle.
　作製したヒータ５は、急速昇降温サイクルを１００回繰り返した時点でも剥離や腐食は観察されなかった。 No peeling or corrosion was observed in the produced heater 5 even when the rapid temperature raising / lowering cycle was repeated 100 times.
〈実施例３〉
　図４は、実施例３における炭化タンタル被覆グラファイト部材を用いて作製されたヒータ５Ａの断面概略図である。実施例３におけるヒータ５Ａは、以下の手順で作製された。はじめに、等方性グラファイトを機械加工して、実施例２と同様の形状のグラファイト基材２Ａを準備した。 <Example 3>
FIG. 4 is a schematic cross-sectional view of the heater 5A manufactured by using the tantalum carbide-coated graphite member according to the third embodiment. The heater 5A in Example 3 was produced by the following procedure. First, isotropic graphite was machined to prepare a graphite base material 2A having the same shape as in Example 2.
　このグラファイト基材２ＡをＣＶＤ装置の反応器内に入れて、真空ポンプを用いて反応器内を真空状態にし、１９００℃まで加熱した。その後、反応器内にアンモニア（ＮＨ３）と三塩化ホウ素（ＢＣｌ３ ）を供給して反応させることによって、グラファイト基材２Ａの表面上に熱分解窒化ホウ素（ＰＢＮ）膜３Ａを形成した。このＰＢＮ膜３Ａの膜厚は５０μｍとし、さらに微量のメタン（ＣＨ４）ガスを添加して、ＰＢＮ中の炭素濃度が１重量％程度になるよう１～２μｍ程度の傾斜層６Ａを設けた。 The graphite base material 2A was placed in the reactor of the CVD apparatus, and the inside of the reactor was evacuated using a vacuum pump and heated to 1900 ° C. Then, ammonia (NH 3 ) and boron trichloride (BCl 3 ) were supplied into the reactor and reacted to form a pyrolysis boron nitride (PBN) film 3A on the surface of the graphite base material 2A. The film thickness of the PBN film 3A was set to 50 μm, and a small amount of methane (CH 4 ) gas was further added to provide an inclined layer 6A having a thickness of about 1 to 2 μm so that the carbon concentration in the PBN was about 1% by weight.
　続いて、ＰＢＮ膜３Ａが成膜された基材２を反応器に収めたままの状態で、反応器内を真空状態にし、反応器内の温度を１６００℃にした。その後、反応器内にメタン（ＣＨ４）ガスと微量のＢＣｌ３ガスを供給して反応させることによって、ＰＢＮ膜３Ａの表面上に中間層７Ａとなるボロンドープグラファイト膜を形成した。このボロンドープグラファイト膜の膜厚は２μｍとした。このときの熱分解炭素中のボロン濃度は６～８重量％とした。 Subsequently, the inside of the reactor was evacuated with the base material 2 on which the PBN film 3A was formed contained in the reactor, and the temperature inside the reactor was set to 1600 ° C. Then, by supplying methane (CH 4 ) gas and a small amount of BCl 3 gas into the reactor and reacting them, a boron-doped graphite film to be an intermediate layer 7A was formed on the surface of the PBN film 3A. The film thickness of this boron-doped graphite film was 2 μm. The boron concentration in the pyrolytic carbon at this time was 6 to 8% by weight.
　続いて、中間層７Ａを形成した基材を反応器に収めたままの状態で、反応器内を真空状態にし、反応器内の温度を１５００℃にして１時間加熱処理を行った。その後、反応器内にメタン（ＣＨ４）ガスと塩化タンタル（ＴａＣｌ５）を供給して反応させることによって、ＰＢＮ膜３Ａの表面上に中間層７Ａを挟んで炭化タンタル（ＴａＣ）膜４Ａを形成した。このＴａＣ膜４Ａの膜厚は５μｍとした。 Subsequently, while the base material on which the intermediate layer 7A was formed was still contained in the reactor, the inside of the reactor was put into a vacuum state, the temperature inside the reactor was set to 1500 ° C., and heat treatment was performed for 1 hour. Then, by supplying methane (CH 4 ) gas and tantalum chloride (TaCl 5 ) into the reactor and reacting them, a tantalum carbide (TaC) film 4A is formed on the surface of the PBN film 3A with the intermediate layer 7A sandwiched between them. did. The film thickness of the TaC film 4A was set to 5 μm.
　反応器内をＮ２で置換し常温まで降温した後、反応器から基材２Ａを取り出して、炭化タンタル被覆グラファイト部材のヒータ５Ａを完成させた。このヒータ５Ａに剥離は見られなかった。 After the inside of the reactor was replaced with N 2 and the temperature was lowered to room temperature, the base material 2A was taken out from the reactor to complete the heater 5A of the tantalum carbide-coated graphite member. No peeling was observed in this heater 5A.
　作製したヒータ５Ａについて通電加熱を行った。まず、ヒータ５Ａを評価用装置内に設置し、装置内を真空排気した。その後、アンモニア（ＮＨ３）を流しながら通電し約３０分間で１５００℃まで加熱して、１５００℃の温度を１０分間保持した。続いて、２００℃まで冷却し、再び１５００℃まで加熱昇温して１０分間保持する急速昇降温サイクルを繰り返した。サイクル毎に剥離状態を確認した。 The produced heater 5A was energized and heated. First, the heater 5A was installed in the evaluation device, and the inside of the device was evacuated. Then, electricity was applied while flowing ammonia (NH 3 ), the mixture was heated to 1500 ° C. in about 30 minutes, and the temperature of 1500 ° C. was maintained for 10 minutes. Subsequently, the rapid ascending / descending temperature cycle of cooling to 200 ° C., heating to 1500 ° C. again, and holding for 10 minutes was repeated. The peeling state was confirmed every cycle.
　作製したヒータ５Ａは、急速昇降温サイクルを１００回繰り返した時点でも剥離や腐食は観察されなかった。 No peeling or corrosion was observed in the produced heater 5A even when the rapid elevating temperature cycle was repeated 100 times.
〈実施例４〉
　はじめに、等方性グラファイトを機械加工して、実施例２と同様の形状のグラファイト基材を準備した。 <Example 4>
First, isotropic graphite was machined to prepare a graphite substrate having the same shape as in Example 2.
　このグラファイト基材をＣＶＤ装置の反応器内に入れて、真空ポンプを用いて反応器内を真空状態にし、１９００℃まで加熱した。その後、反応器内にアンモニア（ＮＨ３）と三塩化ホウ素（ＢＣｌ３ ）を供給して反応させることによって、グラファイト基材の表面上に熱分解窒化ホウ素（ＰＢＮ）膜を形成した。このＰＢＮ膜の膜厚は５０μｍとした。 This graphite substrate was placed in the reactor of the CVD apparatus, and the inside of the reactor was evacuated using a vacuum pump and heated to 1900 ° C. Then, ammonia (NH 3 ) and boron trichloride (BCl 3 ) were supplied into the reactor and reacted to form a pyrolysis boron nitride (PBN) film on the surface of the graphite substrate. The film thickness of this PBN film was 50 μm.
　ＰＢＮ膜を形成したグラファイト基材を一旦反応器から取り出し、表面を純水で洗浄し、ＣＶＤ反応器に入れた。反容器内に清浄な乾燥Ｎ２（露点－７５℃）を常圧で掛け流しながら１６００℃にして３０分加熱処理した後、反容器内を真空状態にして３０分保持した。その後、反応器にメタン（ＣＨ４）ガスと塩化タンタル（ＴａＣｌ５）を供給して反応させることによって、ＰＢＮ膜の表面上に炭化タンタル（ＴａＣ）膜を形成した。このＴａＣ膜の膜厚は５μｍとした。 The graphite base material on which the PBN film was formed was once taken out from the reactor, the surface was washed with pure water, and the mixture was placed in a CVD reactor. A clean dry N 2 (dew point −75 ° C.) was poured into the anti-container at normal pressure to 1600 ° C. for 30 minutes, and then the inside of the anti-container was evacuated and held for 30 minutes. Then, methane (CH 4 ) gas and tantalum chloride (TaCl 5 ) were supplied to the reactor and reacted to form a tantalum carbide (TaC) film on the surface of the PBN film. The film thickness of this TaC film was 5 μm.
〈実施例５〉
　はじめに、等方性グラファイトを機械加工して、実施例２と同様の形状のグラファイト基材を準備した。 <Example 5>
First, isotropic graphite was machined to prepare a graphite substrate having the same shape as in Example 2.
　このグラファイト基材をＣＶＤ装置の反応器内に入れて、真空ポンプを用いて反応器内を真空状態にし、１９００℃まで加熱した。その後、反応器内にアンモニア（ＮＨ３）と三塩化ホウ素（ＢＣｌ３ ）を供給して反応させることによって、グラファイト基材の表面上に熱分解窒化ホウ素（ＰＢＮ）膜を形成した。このＰＢＮ膜の膜厚は５５μｍとした。 This graphite substrate was placed in the reactor of the CVD apparatus, and the inside of the reactor was evacuated using a vacuum pump and heated to 1900 ° C. Then, ammonia (NH 3 ) and boron trichloride (BCl 3 ) were supplied into the reactor and reacted to form a pyrolysis boron nitride (PBN) film on the surface of the graphite substrate. The film thickness of this PBN film was 55 μm.
　ＰＢＮ膜を形成したグラファイト基材を一旦反応器から取り出し、表面を研削し表面粗さＲｍａｘを１２μｍとした。その後研削面を王水で洗浄し、続いて純水で超音波洗浄した後、１２０℃の加熱乾燥を行い、ＣＶＤ反応器に入れた。反応器内を真空とし、さらに１２０℃に加熱後３０分保持した。その後、反応器にメタン（ＣＨ４）ガスと塩化タンタル（ＴａＣｌ５）を供給して反応させることによって、ＰＢＮ膜の表面上に炭化タンタル（ＴａＣ）膜を形成した。このＴａＣ膜の膜厚は５μｍとした。 The graphite base material on which the PBN film was formed was once taken out from the reactor, and the surface was ground to obtain a surface roughness Rmax of 12 μm. After that, the ground surface was washed with aqua regia, then ultrasonically washed with pure water, dried by heating at 120 ° C., and placed in a CVD reactor. The inside of the reactor was evacuated, heated to 120 ° C., and held for 30 minutes. Then, methane (CH 4 ) gas and tantalum chloride (TaCl 5 ) were supplied to the reactor and reacted to form a tantalum carbide (TaC) film on the surface of the PBN film. The film thickness of this TaC film was 5 μm.
　反応器内をアルゴン（Ａｒ）で置換した後、常温まで降温した後、取り出して、炭化タンタル被覆グラファイト部材のヒータ５を完成させた。このヒータ５に剥離は見られなかった。 After replacing the inside of the reactor with argon (Ar), the temperature was lowered to room temperature, and then taken out to complete the heater 5 of the tantalum carbide-coated graphite member. No peeling was observed in this heater 5.
　作製したヒータ５について通電加熱を行った。まず、ヒータ５を評価用装置内に設置し、装置内を真空排気した。その後、アンモニア（ＮＨ３）を流しながら通電し約３０分間で１５００℃まで加熱して、１５００℃の温度を１０分間保持した。続いて、２００℃まで冷却し、再び１５００℃まで加熱昇温して１０分間保持する急速昇降温サイクルを繰り返した。サイクル毎に剥離状態を確認した。 The produced heater 5 was energized and heated. First, the heater 5 was installed in the evaluation device, and the inside of the device was evacuated. Then, electricity was applied while flowing ammonia (NH 3 ), the mixture was heated to 1500 ° C. in about 30 minutes, and the temperature of 1500 ° C. was maintained for 10 minutes. Subsequently, the rapid ascending / descending temperature cycle of cooling to 200 ° C., heating to 1500 ° C. again, and holding for 10 minutes was repeated. The peeling state was confirmed every cycle.
　作製したヒータ５には、急速昇降温サイクルを８０回繰り返した時点でも剥離や腐食は観察されなかった。 No peeling or corrosion was observed in the produced heater 5 even when the rapid temperature raising / lowering cycle was repeated 80 times.
〈実施例６〉
　図５は、実施例６における炭化タンタル被覆グラファイト部材を用いて作製されたウエハトレー１Ｂの断面概略図である。実施例６におけるウエハトレー１Ｂは、以下の手順で作製された。はじめに、等方性グラファイトを機械加工して、実施例１と同様のウエハトレーのグラファイト基材２Ｂを準備した。 <Example 6>
FIG. 5 is a schematic cross-sectional view of a wafer tray 1B manufactured by using the tantalum carbide-coated graphite member according to Example 6. The wafer tray 1B in Example 6 was produced by the following procedure. First, isotropic graphite was machined to prepare a graphite base material 2B of a wafer tray similar to that in Example 1.
　このグラファイト基材２ＢをＣＶＤ装置の反応器内に入れて、真空ポンプを用いて反応器内を真空状態にし、１６００℃まで加熱した。 This graphite base material 2B was placed in the reactor of the CVD apparatus, and the inside of the reactor was evacuated using a vacuum pump and heated to 1600 ° C.
　その後、反応器内にメタンガス（ＣＨ４）と微量の三塩化ホウ素（ＢＣｌ３）を供給して反応させることによって、グラファイト基材２Ｂの表面上に中間層７Ｂとしてボロンドープ熱分解グラファイト（ＢＰＧ）膜を２μｍ形成した。 Then, by supplying methane gas (CH 4 ) and a small amount of boron trichloride (BCl 3 ) into the reactor and reacting them, a boron-doped pyrolytic graphite (BPG) film is formed as an intermediate layer 7B on the surface of the graphite base material 2B. 2 μm was formed.
　その後、反応器内を真空排気した後、反応器内を１８５０℃に加熱し、反応器内にアンモニア（ＮＨ３）と三塩化ホウ素（ＢＣｌ３）を供給して反応させることによって、ＢＰＧの中間層７Ｂの表面上に熱分解窒化ホウ素（ＰＢＮ）膜３Ｂを７５μｍ形成した。７５μｍのＰＢＮ膜３Ｂが形成された時点で、微量のメタンガス（ＣＨ４）を流し、さらに３μｍのカーボンドープ熱分解窒化ホウ素（ＰＢＣＮ）の中間層８Ｂを形成した。 Then, after vacuum exhausting the inside of the reactor, the inside of the reactor is heated to 1850 ° C., and ammonia (NH 3 ) and boron trichloride (BCl 3 ) are supplied into the reactor to react, thereby intermediate between BPG. A pyrolysis boron nitride (PBN) film 3B of 75 μm was formed on the surface of the layer 7B. When the 75 μm PBN film 3B was formed, a small amount of methane gas (CH 4 ) was flowed to further form an intermediate layer 8B of 3 μm carbon-doped pyrolysis boron nitride (PBCN).
　その後、反応器を真空排気した後、反応器内温度を１５００℃に３０分維持した後、反応器内にメタン（ＣＨ４）ガスと塩化タンタル（ＴａＣｌ５）を供給して反応させることによって、中間層８Ｂを設けたＰＢＮ膜の表面上に炭化タンタル（ＴａＣ）膜４Ｂを形成した。 Then, after the reactor was evacuated, the temperature inside the reactor was maintained at 1500 ° C. for 30 minutes, and then methane (CH 4 ) gas and tantalum chloride (TaCl 5 ) were supplied into the reactor to react. A tantalum carbide (TaC) film 4B was formed on the surface of the PBN film provided with the intermediate layer 8B.
　反応器内をＮ２で置換した後、常温まで降温した後、取り出して、炭化タンタル被覆グラファイト部材のウエハトレー１Ｂを完成させた。このウエハトレー１Ｂに剥離は見られなかった。 After substituting the inside of the reactor with N 2 , the temperature was lowered to room temperature, and then the reactor was taken out to complete the wafer tray 1B of the tantalum carbide-coated graphite member. No peeling was observed in this wafer tray 1B.
　作製したウエハトレー１Ｂについて熱衝撃試験を行った。まず、ウエハトレー１Ｂを評価用装置内に設置し、装置内を真空排気した。その後、アンモニア（ＮＨ３）を流しながら約３分間で１５００℃まで急速加熱して、１５００℃の温度を１０分間保持した。続いて、２００℃まで冷却し、再び１５００℃まで加熱昇温して１０分間保持する急速昇降温サイクルを繰り返した。サイクル毎にウエハトレー１Ｂにおける剥離状態を確認した。 A thermal shock test was performed on the produced wafer tray 1B. First, the wafer tray 1B was installed in the evaluation device, and the inside of the device was evacuated. Then, it was rapidly heated to 1500 ° C. in about 3 minutes while flowing ammonia (NH 3 ), and the temperature of 1500 ° C. was maintained for 10 minutes. Subsequently, the rapid ascending / descending temperature cycle of cooling to 200 ° C., heating to 1500 ° C. again and holding for 10 minutes was repeated. The peeling state of the wafer tray 1B was confirmed every cycle.
　作製したウエハトレー１は、急速昇降温サイクルを５０回繰り返した時点でも剥離や腐食は観察されなかった。 No peeling or corrosion was observed in the produced wafer tray 1 even when the rapid elevating temperature cycle was repeated 50 times.
〈比較例１〉
　等方性グラファイトを機械加工して、１００ｍｍ×１００ｍｍ×１０ｍｍのグラファイト基材を準備した。グラファイト基材の一端面にはφ７６ｍｍの凹部が形成されており、角部はＲ形状に面取りが施されている。 <Comparative example 1>
Isotropic graphite was machined to prepare a 100 mm × 100 mm × 10 mm graphite substrate. A recess of φ76 mm is formed on one end surface of the graphite base material, and the corners are chamfered in an R shape.
　このグラファイト基材をＣＶＤ装置の反応器内に入れて、真空ポンプを用いて反応器内を真空状態にし、９００℃まで加熱した。その後、反応器内にメタン（ＣＨ４）ガスと塩化タンタル（ＴａＣｌ５）を供給して反応させることによって、ＰＢＮ膜の表面上に炭化タンタル（ＴａＣ）膜を形成した。このＴａＣ膜の膜厚は５μｍとした。 This graphite substrate was placed in the reactor of the CVD apparatus, the inside of the reactor was evacuated using a vacuum pump, and the mixture was heated to 900 ° C. Then, tantalum carbide (TaC) film was formed on the surface of the PBN film by supplying methane (CH 4 ) gas and tantalum chloride (TaCl 5) into the reactor and reacting them. The film thickness of this TaC film was 5 μm.
　反応器内を常温まで降温した後、取り出して、炭化タンタル被覆グラファイト部材のウエハトレーを完成させた。このウエハトレーに剥離は見られなかった。 After the temperature inside the reactor was lowered to room temperature, it was taken out to complete a wafer tray made of tantalum carbide-coated graphite member. No peeling was observed on this wafer tray.
　作製したウエハトレーについて熱衝撃試験を行った。まず、ウエハトレーを評価用装置内に設置し、装置内を真空排気した。その後、アンモニア（ＮＨ３）を流しながら約３分間で１５００℃まで急速加熱して、１５００℃の温度を１０分間保持した。続いて、２００℃まで冷却し、再び１５００℃まで加熱昇温して１０分間保持する急速昇降温サイクルを繰り返した。サイクル毎に剥離状態を確認した。 A thermal shock test was performed on the produced wafer tray. First, the wafer tray was installed in the evaluation device, and the inside of the device was evacuated. Then, it was rapidly heated to 1500 ° C. in about 3 minutes while flowing ammonia (NH 3 ), and the temperature of 1500 ° C. was maintained for 10 minutes. Subsequently, the rapid ascending / descending temperature cycle of cooling to 200 ° C., heating to 1500 ° C. again, and holding for 10 minutes was repeated. The peeling state was confirmed every cycle.
　作製したウエハトレーは、急速昇降温サイクルを５０回繰り返した時点で、角部にクラックが生じて剥離が発生した。 The manufactured wafer tray had cracks at the corners and peeling occurred when the rapid temperature raising / lowering cycle was repeated 50 times.
〈比較例２〉
　比較例１と同様な方法で、炭化タンタル被覆グラファイト部材のウエハトレーを完成させた。ただし、比較例２ではＴａＣ膜の膜厚を５０μｍとした。 <Comparative example 2>
A wafer tray made of tantalum carbide-coated graphite member was completed in the same manner as in Comparative Example 1. However, in Comparative Example 2, the film thickness of the TaC film was set to 50 μm.
　比較例１と同様に、作製したウエハトレーについて熱衝撃試験を行ったところ、急速昇降温サイクルを１０回繰り返した時点で、角部にクラックが生じて剥離が発生した。 Similar to Comparative Example 1, when a thermal shock test was performed on the produced wafer tray, cracks occurred at the corners and peeling occurred when the rapid elevating temperature cycle was repeated 10 times.
　以上で説明した実施例・比較例から明らかなように、本発明に係る製造方法によれば、高温還元性雰囲気下で使用しても被覆膜の剥離が生じにくい炭化タンタル被覆グラファイト部材を得ることができる。 As is clear from the examples and comparative examples described above, according to the production method according to the present invention, a tantalum carbide-coated graphite member that does not easily peel off the coating film even when used in a high-temperature reducing atmosphere can be obtained. be able to.
　上記実施形態及び実施例は例示であり、本発明の特許請求の範囲に記載された技術的思想と実質的に同一な構成を有し、同様な作用効果を奏するものは、いかなるものであっても本発明の技術的範囲に包含される。 The above-described embodiments and examples are examples, and any one having substantially the same configuration as the technical idea described in the claims of the present invention and exhibiting the same effect and effect. Is also included in the technical scope of the present invention.
１、１Ｂ　ウエハトレー
２、２Ａ、２Ｂ　グラファイト基材
３、３Ａ、３Ｂ　熱分解窒化ホウ素膜
４、４Ａ、４Ｂ　炭化タンタル膜
５、５Ａ　ヒーター
６Ａ　傾斜層
７Ａ、７Ｂ、８Ｂ　中間層 1, 1B Wafer tray 2, 2A, 2B Graphite base material 3, 3A, 3B Pyrolysis boron nitride film 4, 4A, 4B Tantalum carbide film 5, 5A Heater 6A Inclined layer 7A, 7B, 8B Intermediate layer

Claims (10)

  1. 　グラファイト基材を炭化タンタル膜で被覆した炭化タンタル被覆グラファイト部材であって、
    　前記グラファイト基材と前記炭化タンタル膜との間に、熱分解窒化ホウ素膜が形成されていることを特徴とする炭化タンタル被覆グラファイト部材。     A tantalum carbide-coated graphite member in which a graphite base material is coated with a tantalum carbide film.
    A tantalum carbide-coated graphite member, characterized in that a thermally decomposed boron nitride film is formed between the graphite base material and the tantalum carbide film.
  2. 　前記炭化タンタル膜と、前記熱分解窒化ホウ素膜との間に中間層が形成されていることを特徴とする請求項１に記載の炭化タンタル被覆グラファイト部材。 The tantalum carbide-coated graphite member according to claim 1, wherein an intermediate layer is formed between the tantalum carbide film and the pyrolysis boron nitride film.
  3. 　前記グラファイト基材と前記熱分解窒化ホウ素膜との間に中間層が形成されていることを特徴とする請求項１または２に記載の炭化タンタル被覆グラファイト部材。 The tantalum carbide-coated graphite member according to claim 1 or 2, wherein an intermediate layer is formed between the graphite base material and the thermally decomposed boron nitride film.
  4. 　前記炭化タンタル膜の膜厚が、０．５μｍ以上１００μｍ以下であることを特徴とする請求項１から３の何れか１項に記載の炭化タンタル被覆グラファイト部材。 The tantalum carbide-coated graphite member according to any one of claims 1 to 3, wherein the tantalum carbide film has a film thickness of 0.5 μm or more and 100 μm or less.
  5. 　前記グラファイト基材の嵩密度が、１．６ｇ／ｃｍ３以上２．０ｇ／ｃｍ３以下であることを特徴とする請求項１から４の何れか１項に記載の炭化タンタル被覆グラファイト部材。 The tantalum carbide-coated graphite member according to any one of claims 1 to 4, wherein the graphite substrate has a bulk density of 1.6 g / cm 3 or more and 2.0 g / cm 3 or less.
  6. 　前記熱分解窒化ホウ素膜の膜厚が、１０μｍ以上１０００μｍ以下であることを特徴とする請求項１から５の何れか１項に記載の炭化タンタル被覆グラファイト部材。 The tantalum carbide-coated graphite member according to any one of claims 1 to 5, wherein the thermal decomposition boron nitride film has a film thickness of 10 μm or more and 1000 μm or less.
  7. 　請求項１から６の何れか１項に記載の炭化タンタル被覆グラファイト部材を製造する炭化タンタル被覆グラファイト部材の製造方法であって、
    　第１の反応器内でグラファイト基材上に、熱分解窒化ホウ素膜を形成する工程、
    　前記熱分解窒化ホウ素膜が被覆された前記グラファイト基材を、第２の反応器内で、不活性ガス雰囲気もしくは真空下の閉鎖系に保持する工程、
    　前記第２の反応器内で、前記熱分解窒化ホウ素膜が被覆された前記グラファイト基材上に、炭化タンタル膜を被覆する工程、
    　を備えることを特徴とする炭化タンタル被覆グラファイト部材の製造方法。     A method for producing a tantalum carbide-coated graphite member according to any one of claims 1 to 6, wherein the tantalum carbide-coated graphite member is produced.
    A step of forming a pyrolysis boron nitride film on a graphite substrate in a first reactor,
    A step of holding the graphite base material coated with the pyrolysis boron nitride film in an inert gas atmosphere or a closed system under vacuum in a second reactor.
    A step of coating a tantalum carbide film on the graphite substrate coated with the pyrolysis boron nitride film in the second reactor.
    A method for producing a tantalum carbide-coated graphite member.
  8. 　請求項１から６の何れか１項に記載の炭化タンタル被覆グラファイト部材を製造する炭化タンタル被覆グラファイト部材の製造方法であって、
    　グラファイト基材上に、熱分解窒化ホウ素膜を形成する工程と、
    　前記熱分解窒化ホウ素膜が被覆された前記グラファイト基材上に、炭化タンタル膜を被覆する工程が、
    　同一の反応器内で連続的になされることを特徴とする炭化タンタル被覆グラファイト部材の製造方法。     A method for producing a tantalum carbide-coated graphite member according to any one of claims 1 to 6, wherein the tantalum carbide-coated graphite member is produced.
    The process of forming a pyrolysis boron nitride film on a graphite substrate,
    The step of coating the tantalum carbide film on the graphite base material coated with the pyrolysis boron nitride film is
    A method for producing a tantalum carbide-coated graphite member, which is continuously formed in the same reactor.
  9. 　前記熱分解窒化ホウ素膜を形成する工程と前記炭化タンタル膜を被覆する工程との間に、熱分解窒化ホウ素膜の表面を酸洗浄する工程を有することを特徴とする請求項７または８に記載の炭化タンタル被覆グラファイト部材の製造方法。 7. The invention according to claim 7 or 8, wherein the surface of the pyrolysis boron nitride film is acid-cleaned between the step of forming the pyrolysis boron nitride film and the step of coating the tantalum carbide film. A method for manufacturing a tantalum carbide coated graphite member.
  10. 　前記熱分解窒化ホウ素膜の表面粗さＲｍａｘを１０μｍ以上に処理した後に炭化タンタル膜を形成することを特徴とする請求項７から９の何れか１項に記載の炭化タンタル被覆グラファイト部材の製造方法。 The method for producing a tantalum carbide-coated graphite member according to any one of claims 7 to 9, wherein the tantalum carbide film is formed after treating the surface roughness Rmax of the thermally decomposed boron nitride film to 10 μm or more. ..
PCT/JP2020/044124 2019-12-12 2020-11-26 Tantalum carbonate-coated graphite member and method for producing same WO2021117498A1 (en)

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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN114368984A (en) * 2022-01-27 2022-04-19 中电化合物半导体有限公司 Coating of carbon substrate and preparation method and application thereof

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH10506677A (en) * 1994-09-28 1998-06-30 アドヴァンスト・セラミックス・コーポレイション Multilayer flash evaporator
JP2007016272A (en) * 2005-07-06 2007-01-25 Ge Speciality Materials Japan Kk Protective film covered on substrate, and its manufacturing method
WO2010122801A1 (en) * 2009-04-24 2010-10-28 独立行政法人産業技術総合研究所 Apparatus for manufacturing aluminum nitride single crystal, method for manufacturing aluminum nitride single crystal, and aluminum nitride single crystal
JP2015193872A (en) * 2014-03-31 2015-11-05 トーカロ株式会社 Member coated with ceramic spray coating film, and member for semiconductor manufacturing apparatus

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH10506677A (en) * 1994-09-28 1998-06-30 アドヴァンスト・セラミックス・コーポレイション Multilayer flash evaporator
JP2007016272A (en) * 2005-07-06 2007-01-25 Ge Speciality Materials Japan Kk Protective film covered on substrate, and its manufacturing method
WO2010122801A1 (en) * 2009-04-24 2010-10-28 独立行政法人産業技術総合研究所 Apparatus for manufacturing aluminum nitride single crystal, method for manufacturing aluminum nitride single crystal, and aluminum nitride single crystal
JP2015193872A (en) * 2014-03-31 2015-11-05 トーカロ株式会社 Member coated with ceramic spray coating film, and member for semiconductor manufacturing apparatus

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN114368984A (en) * 2022-01-27 2022-04-19 中电化合物半导体有限公司 Coating of carbon substrate and preparation method and application thereof

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