WO2020158657A1 - Film forming apparatus and film forming method - Google Patents

Film forming apparatus and film forming method Download PDF

Info

Publication number
WO2020158657A1
WO2020158657A1 PCT/JP2020/002738 JP2020002738W WO2020158657A1 WO 2020158657 A1 WO2020158657 A1 WO 2020158657A1 JP 2020002738 W JP2020002738 W JP 2020002738W WO 2020158657 A1 WO2020158657 A1 WO 2020158657A1
Authority
WO
WIPO (PCT)
Prior art keywords
gas
film forming
susceptor
mounting table
forming apparatus
Prior art date
Application number
PCT/JP2020/002738
Other languages
French (fr)
Japanese (ja)
Inventor
正幸 原島
志生 佐野
由宗 三澤
充一 中村
洋克 小林
木下　秀俊
Original Assignee
東京エレクトロン株式会社
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by 東京エレクトロン株式会社 filed Critical 東京エレクトロン株式会社
Publication of WO2020158657A1 publication Critical patent/WO2020158657A1/en

Links

Images

Classifications

    • 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
    • H01L21/02—Manufacture or treatment of semiconductor devices or of parts thereof
    • H01L21/02104—Forming layers
    • H01L21/02365—Forming inorganic semiconducting materials on a substrate
    • H01L21/02518—Deposited layers
    • H01L21/02521—Materials
    • H01L21/02524—Group 14 semiconducting materials
    • H01L21/02529—Silicon carbide
    • 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
    • C23C16/42—Silicides
    • 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
    • C23C16/455—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 introducing gases into reaction chamber or for modifying gas flows in reaction chamber
    • 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
    • C23C16/46—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 heating the substrate
    • C—CHEMISTRY; METALLURGY
    • C30—CRYSTAL GROWTH
    • C30B—SINGLE-CRYSTAL GROWTH; UNIDIRECTIONAL SOLIDIFICATION OF EUTECTIC MATERIAL OR UNIDIRECTIONAL DEMIXING OF EUTECTOID MATERIAL; REFINING BY ZONE-MELTING OF MATERIAL; PRODUCTION OF A HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; SINGLE CRYSTALS OR HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; AFTER-TREATMENT OF SINGLE CRYSTALS OR A HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; APPARATUS THEREFOR
    • C30B25/00—Single-crystal growth by chemical reaction of reactive gases, e.g. chemical vapour-deposition growth
    • C30B25/02—Epitaxial-layer growth
    • C—CHEMISTRY; METALLURGY
    • C30—CRYSTAL GROWTH
    • C30B—SINGLE-CRYSTAL GROWTH; UNIDIRECTIONAL SOLIDIFICATION OF EUTECTIC MATERIAL OR UNIDIRECTIONAL DEMIXING OF EUTECTOID MATERIAL; REFINING BY ZONE-MELTING OF MATERIAL; PRODUCTION OF A HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; SINGLE CRYSTALS OR HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; AFTER-TREATMENT OF SINGLE CRYSTALS OR A HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; APPARATUS THEREFOR
    • C30B29/00—Single crystals or homogeneous polycrystalline material with defined structure characterised by the material or by their shape
    • C30B29/10—Inorganic compounds or compositions
    • C30B29/36—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
    • H01L21/02—Manufacture or treatment of semiconductor devices or of parts thereof
    • H01L21/02104—Forming layers
    • H01L21/02365—Forming inorganic semiconducting materials on a substrate
    • H01L21/02518—Deposited layers
    • H01L21/02521—Materials
    • H01L21/02524—Group 14 semiconducting materials
    • H01L21/02532—Silicon, silicon germanium, germanium
    • 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
    • H01L21/02—Manufacture or treatment of semiconductor devices or of parts thereof
    • H01L21/02104—Forming layers
    • H01L21/02365—Forming inorganic semiconducting materials on a substrate
    • H01L21/02518—Deposited layers
    • H01L21/0257—Doping during depositing
    • H01L21/02573—Conductivity type
    • H01L21/02576—N-type
    • 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
    • H01L21/02—Manufacture or treatment of semiconductor devices or of parts thereof
    • H01L21/02104—Forming layers
    • H01L21/02365—Forming inorganic semiconducting materials on a substrate
    • H01L21/02612—Formation types
    • H01L21/02617—Deposition types
    • H01L21/0262—Reduction or decomposition of gaseous compounds, e.g. CVD
    • 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 disclosure relates to a film forming apparatus and a film forming method.
  • Patent Document 1 discloses a film forming apparatus for forming a silicon carbide (SiC) film on a wafer by epitaxial growth.
  • This film forming apparatus has a rotary stage that is connected to a rotary shaft and that is configured to hold a plurality of wafers in a plurality of mounting areas arranged in the circumferential direction with respect to the central axis of the rotary shaft. .. Further, a susceptor configured to accommodate the rotary stage in its internal space, and configured to form a flow of processing gas in the internal space from outside the rotary stage along a direction orthogonal to the central axis. A gas supply mechanism is provided. Further, in the film forming apparatus of Patent Document 1, a heat insulating material is provided in the internal space to reduce variations in temperature within the plane of the wafer on the rotary stage.
  • the technology according to the present disclosure improves the quality of a SiC film formed by a film forming apparatus and a film forming method in which a source gas is supplied by a side flow method.
  • One aspect of the present disclosure is a film forming apparatus that forms a SiC film on a substrate to be processed, and a susceptor that is heated by induction heating and a substrate that is placed inside the susceptor and is rotated with the substrate to be processed placed.
  • a mounting table that rotates around an axis, and a gas that supplies the processing gas from the side to the internal space of the susceptor so that the processing gas flows along the surface of the processing target substrate that is mounted on the mounting table.
  • a supply mechanism is provided, and the internal space of the susceptor preheats the processing gas supplied to the processing target substrate mounted on the mounting table on the upstream side of the mounting table in the flow direction of the processing gas. It has a preheating space.
  • FIG. 1 It is the figure which showed typically the outline of a structure of the film-forming apparatus which concerns on 1st Embodiment. It is sectional drawing which showed the outline of the structure inside the processing container in the film-forming apparatus of FIG. 1 typically. It is sectional drawing which showed the outline of the structure inside the processing container in the conventional film-forming apparatus typically. It is a figure which shows the result of the evaluation test regarding the impurity concentration distribution performed by the present inventors. It is a figure which shows the result of the evaluation test regarding the defect distribution which the present inventors performed. It is a figure which shows the result of the evaluation test regarding the defect distribution which the present inventors performed. FIG.
  • FIG. 3 is a diagram in which a schematic temperature distribution and a schematic impurity concentration distribution are superimposed on each other with the susceptor of FIG. 2 as a reference. It is a figure which shows the result of a confirmation test. It is a schematic cross section for explaining the outline of the composition of the film deposition system concerning a 2nd embodiment. It is a schematic cross section for explaining the outline of the composition of the film deposition system concerning a 3rd embodiment.
  • SiC has been used for electronic devices such as semiconductor power devices.
  • a SiC film is formed on a single crystal substrate by epitaxial growth in which a film having the same orientation as that of the substrate crystal is grown.
  • a processing gas is used for film formation, and there are a downflow method and a side flow method as a method of supplying the processing gas.
  • the processing gas is supplied from above so as to collide with the substrate surface.
  • the side flow method the processing gas is supplied from the side so as to flow along the surface of the substrate.
  • the film forming apparatus disclosed in Patent Document 1 in the internal space of the susceptor configured to accommodate the rotary stage in the internal space, processing is performed from the outside of the rotary stage along a direction orthogonal to the central axis of the rotary stage. Supplying gas. That is, the film forming apparatus disclosed in Patent Document 1 employs the side flow method as the processing gas supply method.
  • the SiC film formed by the film forming apparatus adopting the side flow method it is preferable that the variation in the impurity concentration within the surface of the wafer is further improved.
  • the SiC film formed by the conventional film forming apparatus adopting the side flow method is located on the upstream side and near the outer peripheral portion of the rotary stage.
  • the impurity concentration becomes high in the portion located at.
  • the rising of the impurity concentration in the outer peripheral portion is remarkable. Further, defects are likely to occur in film formation using a gas containing a halogen element.
  • the film formation using the halogen element-containing gas is film formation in which the halogen element-containing gas (hydrogen chloride gas or the like) is supplied together with the Si-containing gas (silane gas or the like) as a source gas.
  • Film formation in which a gas containing both silicon (Si) and a halogen element (dichlorosilane, trichlorosilane, etc.) is supplied as a source gas is also included in the film formation using the halogen element-containing gas.
  • the technology according to the present disclosure improves the quality of the SiC film formed by the film forming apparatus and the film forming method in which the source gas is supplied by the side flow method.
  • FIG. 1 is a diagram schematically showing an outline of the configuration of the film forming apparatus according to the first embodiment.
  • the film forming apparatus 1 of FIG. 1 adopts a side flow method as a processing gas supply method and includes a substantially rectangular parallelepiped processing container 11.
  • An exhaust line 12 is connected to the processing container 11, and the processing container 11 can be adjusted to a desired reduced pressure state (pressure) by the exhaust line 12.
  • the exhaust line 12 has an exhaust pipe 12 a whose one end is connected to the processing container 11.
  • the exhaust pipe 12a is composed of an exhaust manifold or the like, and a vacuum pump 12b such as a mechanical booster pump is connected to the side opposite to the processing container 11 side.
  • a pressure adjusting unit 12c including an APC (automatic pressure control) valve, a proportional control valve or the like for adjusting the pressure inside the processing container 11 is provided. .. Further, the processing container 11 is provided with a pressure gauge 13, and the pressure inside the processing container 11 is adjusted by the pressure adjusting unit 12 c based on the measurement result of the pressure gauge 13.
  • APC automatic pressure control
  • the processing container 11 has a hollow rectangular columnar processing container body 11a having openings at both ends, and flanges 11b connected to both ends of the processing container body 11a so as to close the opening.
  • the processing container body 11a is made of quartz or the like.
  • An induction coil 14 connected to a high frequency power source 14a is provided outside the processing container body 11a.
  • the induction coil 14 heats the processing target substrate.
  • the induction coil 14 induction-heats the susceptor 30 and the like described below, and heats the processing target substrate and the like by radiant heat and heat conduction from the induction-heated susceptor 30.
  • the induction heating by the induction coil 14 has a constant heating amount per unit length in the flow direction of the processing gas.
  • a gas supply mechanism 15 is configured to supply a raw material gas, which is a raw material for film formation, into the processing container 11.
  • the gas supply mechanism 15 has a gas supply pipe 15a connected to the processing container 11 and gas supply pipes 15b 1 to 15b 6 connected to the gas supply pipe 15a.
  • the gas supply pipes 15b 1 to 15b 6 are provided with mass flow controllers (MFC) 15c 1 to 15c 6 and valves 15d 1 to 15d 6 , respectively.
  • a gas supply source 15e 1 is connected to the gas supply pipe 15b 1 , and a silane (SiH 4 ) gas is supplied from the supply source 15e 1 .
  • gas supply sources 15e 2 to 15e 6 are connected to the gas lines 15b 2 to 15b 6 , respectively, and propane (C 3 H 8 ) gas and hydrogen (H 2 ) gas are supplied from the gas supply sources 15e 2 to 15e 6.
  • Nitrogen gas (N 2 gas), hydrogen chloride (HCl) gas, and argon (Ar) gas are supplied.
  • SiH 4 gas, C 3 gas from the gas supply pipes 15b 1 to 15b 5 are used as a source gas for the film formation.
  • the H 8 gas, the H 2 gas, the N 2 gas, and the HCl gas are supplied to the processing container 11.
  • a gas supply source for TMA (trimethylaluminum) gas, a gas supply pipe, and the like may be provided for forming the p-type SiC film.
  • one of the H 2 gas and the Ar gas from the gas supply pipes 15b 3 and 15b 6 or these gases are It is mixed and supplied to the processing container 11.
  • the film forming apparatus 1 also includes a control unit 50.
  • the control unit 50 is, for example, a computer and has a program storage unit (not shown).
  • the program storage unit stores a program for controlling the MFCs 15c 1 to 15c 6 , the valves 15d 1 to 15d 6 , the high frequency power supply 14a, the pressure adjusting unit 12c, and the like to perform the film forming process.
  • the program may be recorded in a computer-readable storage medium, and may be installed in the control unit 50 from the storage medium.
  • FIG. 2 is a cross-sectional view schematically showing an outline of the configuration inside the processing container 11 in the film forming apparatus 1 of FIG.
  • a mounting table 20 on which a SiC substrate W (hereinafter, may be abbreviated as “substrate W”) as a processing target substrate is mounted, and a mounting table.
  • a rotation shaft 21 that rotates the 20 and supports the mounting table 20 is provided.
  • a susceptor 30 heated by induction heating by the induction coil 14 is provided inside the processing container 11.
  • the mounting table 20 is arranged in the susceptor 30 such that the mounting surface (the upper surface in the drawing) is horizontal.
  • the substrate W mounted on the mounting table 20 rotates about the rotary shaft 21.
  • the mounting table 20 is formed of a conductive material having high heat resistance and easy to be heated by induction heating, and is composed of, for example, a graphite member whose upper surface is coated with SiC.
  • the rotary shaft 21 has one end connected to the center of the lower part of the mounting table 20, and the other end penetrating the bottom of the processing container 11 to reach the lower part thereof and connected to a rotary drive mechanism (not shown).
  • a rotary drive mechanism not shown.
  • the susceptor 30 has an internal space S that accommodates the mounting table 20.
  • the susceptor 30 is formed in a rectangular parallelepiped shape having openings on two side surfaces facing each other, and the processing gas is supplied from the opening on one side surface and the processing gas is discharged from the opening on the other side surface. Has become.
  • the processing gas is in a direction orthogonal to the central axis P1 of the rotating shaft 21 and in a direction parallel to the processing target surface (the upper surface in the drawing) of the substrate W on the mounting table 20. Supplied and discharged.
  • the details of the internal space S of the susceptor 30 will be described later.
  • the susceptor 30 is formed of a conductive material having high heat resistance and easy to be heated by induction heating, and is composed of, for example, a graphite member coated with SiC.
  • a heat insulating material 31 is provided so as to cover the outer periphery of the susceptor 30.
  • the heat insulating material 31 insulates the susceptor 30 and the processing container 11 from each other, and is formed in a rectangular parallelepiped shape similar to the susceptor 30. Further, on the side surface of the heat insulating material 31, an opening communicating with the above-described opening on the side surface of the susceptor 30 is provided.
  • the heat insulating material 31 is formed using, for example, a fibrous carbon material having a large porosity.
  • a holding member 32 is provided so as to cover the heat insulating material 31.
  • the holding member 32 has a main body portion 32a having a space for accommodating the susceptor 30 covered with the heat insulating material 31 therein, and the internal space S in the susceptor 30 through the above-described openings on the side surfaces of the susceptor 30 and the heat insulating material 31.
  • a pair of conduits 32b 1 and 32b 2 communicating with each other.
  • An upstream end (hereinafter, also referred to as “air supply side”) of the processing gas in the flow direction 32b 1 is connected to the flange 11b on the gas supply mechanism 15 side at the end opposite to the susceptor 30. ing.
  • the processing gas from the gas supply mechanism 15 can be supplied to the internal space S in the susceptor 30.
  • the downstream side (hereinafter, also referred to as “exhaust side” in some cases) 32b 2 in the flow direction of the processing gas, the end opposite to the susceptor 30 is connected to the flange 11b on the exhaust line 12 side. ing.
  • exhaust side exhaust side
  • the holding member 32 is made of, for example, quartz. The holding member 32 is supported on the inner surface of the processing container 11 via a columnar support portion 33.
  • the internal space S of the susceptor 30 is further configured to have a mounting table space S1 and a preheating space S2 in the processing container 11 configured as described above.
  • the mounting table space S1 is a space in which the mounting table 20 is located.
  • the preheating space S2 is located upstream of the mounting table space S1, that is, the mounting table 20 in the flow direction of the processing gas (hereinafter, also referred to as “gas flow direction”), and is supplied to the mounting table space S1 during film formation. This is a space where the processing gas is preheated by the susceptor 30.
  • the preheating space S2 is formed by offsetting the rotary shaft 21 of the mounting table 20 to the exhaust side with respect to the susceptor 30. More specifically, the preheating space S2 is formed by locating the central axis P1 of the rotating shaft 21 of the mounting table 20 on the downstream side of the central axis P2 of the susceptor 30 in the gas flow direction.
  • the central axes P1 to P3 of the processing container 100, the mounting table 101, and the susceptor 102 are generally aligned with each other. ..
  • the position of the central axis P1 of the mounting table 20 is offset to the exhaust side with respect to the central axis P3 of the processing container 11 with respect to the general structure described above, and the position is offset.
  • the structure is such that the susceptor 30 is extended to the exhaust side by an amount. Therefore, in the structure of the present embodiment, the distance from the flange 11b on the exhaust line 12 side to the susceptor 30 is shorter than the distance from the flange 11b on the gas supply mechanism 15 side to the susceptor 30.
  • a wraparound prevention member 34 is provided in the preheating space S2 so as to close the space between the air supply side end of the mounting table 20 and the air supply side inner peripheral end of the susceptor 30.
  • the wraparound prevention member 34 is for preventing the processing gas from wrapping around to the back side of the mounting table 20 or the like.
  • the wraparound prevention member 34 is formed of a material having high heat resistance, and is formed of, for example, a graphite member whose upper surface is coated with SiC.
  • the substrate W is loaded into the processing container 11 (step 1). Specifically, the substrate W is transferred from the outside of the film forming apparatus 1 via a gate valve (not shown) and the gas supply side conduit 32b 1 by a transfer means (not shown) outside the film forming apparatus 1.
  • the processing container 11 is loaded into the internal space S of the susceptor 30 and is positioned above the mounting table 20.
  • the elevating part (not shown) is raised, and the substrate W is supported by the elevating part.
  • the transport means is retracted from the processing container 11, and the elevating unit is lowered, so that the substrate W is placed on the mounting table 20.
  • the substrate W may be placed not directly on the mounting table 20 but via a holder (not shown) that is a disk-shaped member.
  • the source gas and the carrier gas as the processing gas from the gas supply mechanism 15 are supplied so as to flow along the surface to be processed of the substrate W in the internal space S.
  • the high frequency power from the high frequency power supply 14 a is applied to the induction coil 14.
  • the substrate W is heated, and an n-type SiC film is formed on the substrate W by epitaxial growth (step 2).
  • the valves 15d 1 to 15d 5 are opened, the flow rate is adjusted by the MFCs 15c 1 to 15c 5 , and SiH 4 gas, C 3 H 8 gas, and H 2 gas are introduced into the internal space S in the processing container 11. , N 2 gas, and HCl gas are supplied.
  • high frequency power is applied to the induction coil 14 from the high frequency power source 14a to inductively heat the holder, the mounting table 20, and the susceptor 30, and the substrate W is heated by radiation and heat conduction from these.
  • the processing gas supplied to the mounting table space S1 is heated in the preheating space S2.
  • the pressure inside the processing container 11 is, for example, 10 Torr to 600 Torr, and the temperature of the substrate W is, for example, 1500° C. to 1700° C.
  • the HCl gas is supplied together with the SiH 4 gas, but the supply of the HCl gas may be omitted.
  • the supply of HCl gas suppresses the formation of Si—Si bonds in the vapor layer due to the formation of SiCl 2 by chlorine (Cl), so that high-speed growth is possible.
  • HCl gas By supplying the HCl gas, it is possible to suppress the generation of by-products in the processing container 11 or the like due to the etching effect of HCl, so that the time required for the by-product removal processing can be shortened, so that the productivity is improved.
  • HCl gas other halogen-containing gas such as hydrogen fluoride gas or dichlorosilane (SiH 2 Cl 2 ) gas may be supplied.
  • the substrate W is unloaded from the processing container 11 (step 3). Specifically, the valves 15d 1 to 15d 5 are closed, the supply of the source gas and the carrier gas is stopped, and then the elevating part is raised to raise the substrate W. Then, the transfer means outside the film forming apparatus 1 is inserted into the processing container 11 via the gate valve and the conduit 32b 1 and positioned below the substrate W. After that, the substrate W is transferred from the elevating unit to the transfer means by lowering the elevating unit, and the substrate W is unloaded from the processing container 11 by retracting the transfer unit from the processing container 11.
  • the supply of the high frequency power to the induction coil 14 may be interrupted while the substrate W is being carried out, the high frequency power is supplied to the induction coil 14 while controlling the temperature of the mounting table 20 and the susceptor 30 to be optimum in the next process. Is preferably supplied.
  • step 1 After the substrate W is unloaded, the process is returned to step 1, another substrate W is loaded into the processing container 11, and the processes of steps 1 to 3 are repeated.
  • the operation and effect of this embodiment will be described.
  • the n-type SiC film formed by using the film forming apparatus adopting the side flow method and having the conventional general structure shown in FIG. 3 a portion located in a region close to the outer peripheral portion of the mounting table 101.
  • the impurity concentration was high.
  • this tendency was remarkable in film formation using a gas containing a halogen element.
  • the “conventional film forming apparatus” is a film forming apparatus having the structure of FIG.
  • the SiC film is an “n-type SiC film” unless otherwise specified.
  • FIG. 4 shows the result of one of the evaluation tests conducted by the present inventors in order to eliminate the above-mentioned non-uniformity of impurity concentration.
  • FIG. 4 shows the impurity concentration distribution of the SiC film formed by using the conventional film forming apparatus.
  • a film was formed by supplying SiH 4 gas, C 3 H 8 gas, H 2 gas, and N 2 gas as processing gas (hereinafter referred to as “normal epi”), and SiH 2 Cl 2 as processing gas.
  • normal epi processing gas
  • halogen epi SiH 2 Cl 2
  • the impurity concentration of the SiC film is highest at the end on the air supply side, decreases along the gas flow direction, and is 1/3 of the diameter of the holder. After passing the part of, it increases again along the gas flow direction. Since such an impurity concentration distribution does not occur in film formation when the mounting table 101 is not rotated, in the SiC film formed by rotating the mounting table 101, a portion located in a region near the outer periphery of the mounting table 101 is formed. It is considered that the impurity concentration becomes high.
  • the non-uniformity of the impurity concentration distribution as shown in FIG. 4 occurs due to the following reasons. That is, in the conventional film forming apparatus, the supplied source gas is rapidly heated when passing through the susceptor 102. Therefore, the gas temperature of the raw material gas is low on the supply side and increases toward the exhaust side. Therefore, the amount of C 3 H 8 decomposed into a precursor from around 800° C. is small on the air supply side and increases toward the exhaust side. On the other hand, SiH 4 is decomposed into a precursor from a low temperature of about 400°C.
  • the ratio of the number of carbon (C) atoms in the precursor to the number of Si atoms in the precursor in the atmosphere (C/Si ratio) is very low.
  • the amount of N incorporated into the film increases.
  • the Si concentration decreases due to the consumption of Si due to the reaction with the inner wall of the susceptor 102 and the like, whereas the decomposition amount of C 3 H 8 increases as described above.
  • the /Si ratio becomes higher.
  • N uptake is reduced.
  • the concentration of C 2 H 2 which is a precursor of C in the atmosphere is saturated, while the amount of N 2 decomposed increases as the temperature rises, so the amount of N taken up again increases. To do.
  • the non-uniformity of the impurity concentration distribution as described above occurs.
  • the heating amount by the susceptor 102 is increased, the exhaust gas is increased.
  • the temperature of the processing gas on the side is also increased, the amount of N 2 decomposed on the exhaust side is increased, and the impurity concentration is increased.
  • the heating amount by the susceptor 102 is reduced in order to lower the temperature of the processing gas on the exhaust side to reduce the decomposition amount of N 2 and lower the impurity concentration on the exhaust side, the temperature of the processing gas on the air supply side also decreases. ..
  • FIG. 5 and 6 are diagrams showing a defect map of the surface of the SiC film formed in the evaluation test in which the results of FIG. 4 are obtained
  • FIG. 5 shows the film surface obtained by the normal epitaxy
  • defect maps are shown along the gas flow direction.
  • the upper part of the defect map located on the upper side of the figure corresponds to the air supply side end of the substrate placed on the air supply side
  • the lower part of the defect map located on the lower side of the figure is mounted on the exhaust side. It corresponds to the exhaust side end of the placed substrate.
  • the region R1 with many defects exists only in a part on the air supply side, but most of the region R1 has few defects.
  • the region R2 having many defects is not limited to a part on the air supply side, but extends from the part corresponding to the center of the holder or the mounting table 101 to the end on the exhaust side. Exists and occupies a wide area.
  • the defects on the air supply side are mainly caused by Si droplets in which Si is aggregated, and the defects on the exhaust side are mainly crystal defects such as triangular defects.
  • the surface of the halogen epi was roughened toward the exhaust side.
  • the reason why many defects are generated on the surface of the halogen epi is supposed to be as follows, in consideration of the observation result with the above-mentioned optical microscope. That is, it is presumed that the above-mentioned defects are derived from the etch pits generated by the etching with the SiH 2 Cl 2 gas in the high temperature region on the exhaust side. Specifically, the SiH 2 Cl 2 gas excessively activated on the exhaust side where the processing gas has a high temperature damages the surface of the substrate W, and defects are introduced into the grown crystal in the damaged part.
  • a preheating space S2 is provided on the supply side of the mounting table space S1 of the substrate W in the internal space of the susceptor 30, and the processing gas supplied to the mounting table space S1 is preheated in the preheating space S2.
  • the temperature of the processing gas rises along the gas flow direction.
  • the preheating space S2 since the preheating space S2 is provided, the temperature of the process gas on the air supply side is raised as compared with the conventional film forming apparatus while suppressing the temperature rise of the process gas on the exhaust side in the mounting table space S1. be able to.
  • the temperature rise of the processing gas on the exhaust side in the mounting table space S1 can be suppressed and the supply side can be reduced.
  • the temperature of the processing gas can be raised more than that of the conventional film forming apparatus. Further, at this time, if the length of the preheating space S2 in the gas flow direction is increased, the temperature of the processing gas on the exhaust side in the mounting table space S1 can be lowered while the temperature of the processing gas on the supply side can be increased. ..
  • FIG. 7 is a diagram showing a schematic temperature distribution and a schematic impurity concentration distribution with the susceptor 30 as a reference in an overlapping manner.
  • the solid line shows the temperature distribution of the processing gas when the mounting table 20 is not rotated
  • the dotted line shows the temperature distribution of the processing gas temperature distribution when the mounting table 20 is rotated.
  • the imaginary line shows the impurity concentration distribution, and specifically shows the amount of N as an impurity that can be taken in at the position during film formation for each position in the gas flow direction.
  • A1 indicates the air supply side end of the susceptor 30
  • A2 indicates the position corresponding to the air supply side end of the mounting table space in the conventional film forming apparatus
  • A3 indicates the mounting table space in the present embodiment.
  • the air supply side end of S1 is shown.
  • A4 indicates a position corresponding to the exhaust side end of the mounting table space in the conventional film forming apparatus
  • A5 indicates the exhaust side end of the mounting table space S1 in the present embodiment.
  • the preheating space S2 is provided as described above.
  • the air supply side end A1 of the susceptor 30 is closer to the air supply side end A3 of the mounting table space S1 in this embodiment than to the position A2 corresponding to the air supply side end of the mounting table space in the conventional film forming apparatus. It is located far from. Therefore, in this embodiment, since the temperature of the processing gas is high even at the air supply side end A3 of the mounting table space S1, it is possible to reduce the amount of N taken in by the site competition effect. Therefore, it is possible to reduce the impurity concentration of the SiC film formed at the air supply side end of the mounting table space S1.
  • the nitrogen intake amount is small on the air supply side and gradually increases toward the exhaust side. Therefore, by rotating the mounting table 20 during film formation, it is possible to obtain a SiC film having an in-plane uniform impurity concentration. That is, the quality of the SiC film can be improved.
  • the site competition means that, in the incorporation of the dopant into the SiC film, N replaces the C site and aluminum (Al) replaces the Si site. Therefore, competition between C or Si and the dopant occurs on the surface, and the dopant It will affect the uptake of. For example, in the case of a low C/Si ratio, there is a small amount of C that competes with N, resulting in a high N concentration.
  • the region where the amount of N taken up is large when the film is formed, the region on the air supply side where the amount of N taken up is large due to the site competition effect, and the region where N is taken up by the thermal decomposition of N 2 gas at high temperature.
  • film formation is not performed in the region on the air supply side, but film formation is performed only in the region on the exhaust side. Therefore, since the mode of capturing N is narrowed down, the condition for optimizing the impurity concentration can be easily obtained.
  • the structure having the preheating space S2 as described above, it is possible to raise the temperature of the air supply side process gas while lowering the temperature of the exhaust side process gas in the mounting table space S1. Therefore, with respect to the halogen epi where the number of defects increases as the temperature of the processing gas increases, by using the film forming apparatus of this embodiment, a high-quality SiC film having a uniform impurity concentration in the surface and few defects is formed. can do.
  • the present embodiment achieves the following points (A) to (C) by offsetting the mounting table 20 to the exhaust side and providing the preheating space S2.
  • A Avoiding film formation in a region on the air supply side where a film with a high impurity concentration is formed and Si droplets are generated
  • B Improvement of impurity concentration distribution and defects due to temperature rise on the air supply side in the mounting table space S1
  • C Prevention of introduction of defects in halogen epi due to temperature drop on the exhaust side in the mounting table space S1 Therefore, even in the side-flow method with a wide reaction region, high-quality halogen epi can be achieved by high-speed growth and high throughput.
  • a SiC film can be obtained.
  • the impurity concentration at the air supply side end is 10 17 cm ⁇ 3 level, and the impurity concentration at the air supply end is The fall is very large. In this embodiment, film formation in such a region is avoided.
  • the structure of the present embodiment is a structure in which the distance from the flange 11b on the exhaust line 12 side to the susceptor 30 is shorter than the distance from the flange 11b on the gas supply mechanism 15 side to the susceptor 30. .. Since the flange 11b on the exhaust line 12 side is close in this way, the induction magnetic field that should be used for heating the susceptor 30 is used for heating the flange 11b, and the temperature on the exhaust side of the susceptor 30 becomes lower than in the conventional case. That is, the temperature of the processing gas on the exhaust side in the mounting table space S1, which tends to increase in the side-flow method, can be lowered. Therefore, a high-quality SiC film with fewer defects can be formed during the halogen epitaxy.
  • the mounting tables 20 and 101 of the film forming apparatus used in this test have a diameter of 345 mm, and the mounting table 20 of the film forming apparatus of the present embodiment is offset by 70 mm from the center of the susceptor 30 toward the exhaust side.
  • the offset film was formed longer than the conventional film forming apparatus.
  • three substrates W having a diameter of about 75 mm are mounted on the mounting tables 20 and 101 via the holder having a diameter of about 300 mm, and the mounting tables 20 and 101 are rotated. There wasn't.
  • the etching amount on the air supply side in the mounting table space was small and the etching amount on the exhaust side was large. Since the etching amount corresponds to the temperature of the processing gas, in other words, in the conventional film forming apparatus, the temperature of the processing gas is low on the air supply side and high on the exhaust side in the mounting table space. It was On the other hand, in the apparatus of this embodiment, the amount of etching on the air supply side in the mounting table space S1 is higher than that in the conventional film forming apparatus, and the rate of increase in the amount of etching toward the exhaust side in the mounting table space S1 is It was small. That is, in the film forming apparatus of the present embodiment, the temperature of the process gas on the air supply side is high and the rate of temperature rise can be suppressed.
  • the film forming apparatus of the present embodiment it is possible to raise the temperature of the supply gas side process gas while lowering the temperature of the exhaust side process gas in the mounting table space S1. I understand. That is, according to the film forming apparatus of the present embodiment, it is possible to obtain a high-quality SiC film such as a SiC film having an in-plane uniform impurity concentration.
  • the etching amount was smaller on the exhaust side, that is, the processing gas temperature was lower than that of the conventional film forming apparatus. This is because, as described above, since the flange 11b on the exhaust line 12 side is close, the induction magnetic field that should be used to heat the susceptor 30 is used to heat the flange 11b, and the temperature on the exhaust side of the susceptor 30 becomes lower than in the conventional case. It is considered that what is being done is affecting.
  • the offset amount of the mounting table 20 is 70 mm, but as is clear from FIG. 4, similar results can be obtained if the offset amount is in the range of 60 to 120 mm. it can.
  • FIG. 9 is a diagram for explaining the outline of the configuration of the film forming apparatus according to the second embodiment, and is a schematic cross-sectional view showing a state around the processing container 11 included in the film forming apparatus.
  • the density of the induction coil 14 is uniform in the gas flow direction. Therefore, the amount of heating per unit length in the gas flow direction by the induction heating using the induction coil 14 was constant.
  • the density of the induction coil 14 is larger on the air supply side than on the exhaust side with respect to the rotating shaft 21.
  • the heating amount per unit length in the gas flow direction by the induction heating using the induction coil 14 is larger on the air supply side than on the exhaust side with respect to the rotating shaft 21.
  • the method of increasing the heating amount per unit length in the gas flow direction by the induction heating using the induction coil 14 from the exhaust side to the supply side with respect to the rotating shaft 21 may be the following method. That is, this is a method in which the high-frequency power applied to the induction coil 14 is made larger on the air supply side than on the exhaust side with respect to the rotating shaft 21.
  • the high frequency power supply 14a may be separately provided on the exhaust side and the air supply side.
  • FIG. 10 is a diagram for explaining the outline of the configuration of the film forming apparatus according to the third embodiment, and is a schematic cross-sectional view showing a state around the processing container 11 included in the film forming apparatus.
  • the reason why the impurity concentration is high on the air supply side in the conventional film forming apparatus is that the C/Si ratio is low as described above.
  • the air supply side conduit 32b 1 as a gas introduction portion is formed in multiple stages, SiH 4 gas is supplied from the upper stage, and another process gas (for example, H 2 2 gas and C 3 H 8 gas) are supplied.
  • the diffusion of Si into the substrate W can be delayed, and the C/Si ratio in the vicinity of the substrate surface on the air supply side can be increased. Therefore, the impurity concentration on the air supply side can be further reduced. Therefore, the uniformity of the impurity concentration can be further improved.
  • the film forming rate is highest on the air supply side and decreases on the air exhaust side. This phenomenon corresponds to a large consumption of Si that controls the growth on the air supply side and a decrease in the Si density toward the exhaust side. Therefore, as in the present embodiment, the gas supply side conduit 32b 1 is formed in multiple stages, the SiH 4 gas is supplied from the upper stage, and the other process gas is supplied from the lower stage, so that Si on the supply side is reduced. Diffusion to the substrate W can be delayed and growth can be suppressed.
  • the growth rate is fast on the air supply side means that a large amount of Si is consumed for the growth in the preheating space S2.
  • the growth rate can be slowed on the air supply side. Therefore, it is possible to prevent a large amount of Si from being consumed for growth in the preheating space S2.
  • the placement table 20 is offset, it is possible to eliminate the occurrence of a high-concentration portion of impurities on the air supply side.
  • the fluctuation of the impurity concentration on the air supply side is large, and the exhaust gas is exhausted. On the side, the fluctuation of the impurity concentration is gentle.
  • the proportion of the portion that grows in the region where the above-mentioned fluctuation of the impurity concentration is gentle increases. Therefore, impurities when the mounting table 20 is rotated during film formation are increased. The uniformity of concentration can be further improved.
  • the upper portion of the conduit 32b 1 is thicker than the lower portion. This is because the substrate W is loaded and unloaded through the upper stage of the conduit 32b 1 .
  • the partition 40 is provided which separates the upper and lower conduits 32 b 1.
  • the partition 40 is provided. You don't have to.
  • both the Si-containing gas and the halogen-containing gas were supplied, but a gas containing both silicon and a halogen element, for example, SiCl 4 gas, trichlorosilane (SiHCl 3 ) gas, or SiH 2 Cl. 2 gas, monochlorosilane (SiH 3 Cl) gas, tetrafluorosilane (SiF 4 ) gas, trifluorosilane (SiHF 3 ) gas, difluorosilane gas (SiH 2 F 2 ) gas, monofluorosilane (SiH 3 F) gas It may be supplied.
  • the halogen-containing gas may be supplied together with the gas containing both silicon and the halogen element.
  • each embodiment can be applied to the growth of the p-type SiC film.
  • the tendency of the distribution of the impurity concentration is opposite between the n-type SiC film and the p-type SiC film.
  • the impurity concentration depends on the substrate temperature as compared with the n-type SiC film.
  • by preheating the temperature of the processing gas on the air supply side of the mounting table space S1 it becomes difficult for the substrate W to be cooled by the processing gas, and thus the uniformity of the substrate temperature is improved.
  • a film forming apparatus for forming a SiC film on a substrate to be processed A susceptor heated by induction heating, A mounting table which is disposed in the susceptor and rotates about a rotation axis in a state where a substrate to be processed is mounted,
  • the processing gas flows along the surface of the processing target substrate placed on the mounting table, and has a gas supply mechanism that supplies the processing gas from the side to the internal space of the susceptor,
  • the internal space of the susceptor has a preheating space for preheating the processing gas supplied to the processing target substrate mounted on the mounting table, on the upstream side of the mounting table in the flow direction of the processing gas. apparatus.
  • the upstream side (supply air) in the flow direction of the processing gas is controlled.
  • the temperature of the processing gas (side) can be raised more than that of the conventional film forming apparatus. Further, it is possible to raise the temperature of the process gas on the air supply side while lowering the temperature of the process gas on the exhaust side in the space where the mounting table is located. Therefore, it is possible to make the impurity concentration distribution uniform in the SiC film formed by supplying the source gas by the side flow method. Further, when a halogen-containing gas is also supplied as the processing gas, it is possible to reduce defects in the SiC film. That is, it is possible to improve the quality of the SiC film formed by the film forming apparatus to which the source gas is supplied by the side flow method.
  • the preheating space is formed by the rotation axis with respect to the mounting table being located downstream of the central axis of the susceptor in the flow direction of the processing gas, so that the preheating space is formed.
  • Membrane device
  • the amount of heating per unit length in the flow direction of the processing gas by induction heating is such that the portion upstream of the rotation shaft in the flow direction of the processing gas is the rotation shaft in the flow direction of the processing gas.
  • the film forming apparatus according to (1) or (2) which is larger than a portion on a more downstream side. According to the above (3), the quality of the SiC film can be easily improved.
  • a film forming method for forming a SiC film on a substrate to be processed by a film forming apparatus The film forming apparatus, A susceptor heated by induction heating, A mounting table that is disposed in the susceptor and that rotates about a rotation axis in a state in which a substrate to be processed is mounted,
  • the film forming method is A step of introducing the processing gas from the side to the internal space of the susceptor so that the processing gas flows along the surface of the processing target substrate placed on the mounting table, A preheating space located upstream of the mounting table in the flow direction of the processing gas, and preheating the processing gas supplied to the processing target substrate mounted on the mounting table. ..

Abstract

This film forming apparatus for forming a SiC film on a substrate to be treated has: a susceptor to be heated by induction heating; a placement base which is disposed within the susceptor and rotates about a rotation axis in a state in which the substrate to be treated is placed thereon; and a gas supply mechanism for supplying a treatment gas from a side to the internal space of the susceptor so that the treatment gas flows along the surface of the substrate to be treated placed on the placement base. The internal space of the susceptor has, on the upstream side of the placement base in the direction of flow of the treatment gas, a pre-heating space in which the treatment gas is pre-heated before being supplied to the substrate to be treated placed on the placement base.

Description

成膜装置及び成膜方法Film forming apparatus and film forming method
　本開示は、成膜装置及び成膜方法に関する。 The present disclosure relates to a film forming apparatus and a film forming method.
　特許文献１には、ウェハ上に炭化ケイ素（ＳｉＣ）膜をエピタキシャル成長によって形成する成膜装置が開示されている。この成膜装置は、回転軸に接続されると共に、当該回転軸の中心軸線に対して周方向に配列された複数の載置領域において複数のウェハを保持するように構成された回転ステージを有する。また、回転ステージをその内部空間に収容するよう構成されたサセプタと、上記内部空間において、回転ステージの外側から上記中心軸線に直交する方向に沿った処理ガスの流れを形成するように構成されたガス供給機構が設けられている。また、特許文献１の成膜装置では、上記内部空間に断熱材を設け、回転ステージ上のウェハの面内における温度のバラツキを低減させている。 Patent Document 1 discloses a film forming apparatus for forming a silicon carbide (SiC) film on a wafer by epitaxial growth. This film forming apparatus has a rotary stage that is connected to a rotary shaft and that is configured to hold a plurality of wafers in a plurality of mounting areas arranged in the circumferential direction with respect to the central axis of the rotary shaft. .. Further, a susceptor configured to accommodate the rotary stage in its internal space, and configured to form a flow of processing gas in the internal space from outside the rotary stage along a direction orthogonal to the central axis. A gas supply mechanism is provided. Further, in the film forming apparatus of Patent Document 1, a heat insulating material is provided in the internal space to reduce variations in temperature within the plane of the wafer on the rotary stage.
特開２０１６－１００４６２号公報Japanese Patent Laid-Open No. 2016-100462
　本開示にかかる技術は、サイドフロー方式で原料ガスが供給される成膜装置及び成膜方法によって形成されるＳｉＣ膜の品質を向上させる。 The technology according to the present disclosure improves the quality of a SiC film formed by a film forming apparatus and a film forming method in which a source gas is supplied by a side flow method.
　本開示の一態様は、処理対象基板にＳｉＣ膜を形成する成膜装置であって、誘導加熱により加熱されるサセプタと、前記サセプタ内に配置され、処理対象基板が載置された状態で回転軸を中心に回転する載置台と、前記載置台に載置された処理対象基板の表面に沿って処理ガスが流れるように、前記サセプタの内部空間に対し側方から前記処理ガスを供給するガス供給機構と、を有し、前記サセプタの内部空間は、前記処理ガスの流れ方向における前記載置台より上流側に、前記載置台に載置された処理対象基板に供給される前記処理ガスを予熱する予熱空間を有する。 One aspect of the present disclosure is a film forming apparatus that forms a SiC film on a substrate to be processed, and a susceptor that is heated by induction heating and a substrate that is placed inside the susceptor and is rotated with the substrate to be processed placed. A mounting table that rotates around an axis, and a gas that supplies the processing gas from the side to the internal space of the susceptor so that the processing gas flows along the surface of the processing target substrate that is mounted on the mounting table. A supply mechanism is provided, and the internal space of the susceptor preheats the processing gas supplied to the processing target substrate mounted on the mounting table on the upstream side of the mounting table in the flow direction of the processing gas. It has a preheating space.
　本開示によれば、サイドフロー方式で原料ガスが供給される成膜装置及び成膜方法によって形成されるＳｉＣ膜の品質を向上させることができる。 According to the present disclosure, it is possible to improve the quality of a SiC film formed by a film forming apparatus and a film forming method in which a source gas is supplied by a side flow method.
第１実施形態に係る成膜装置の構成の概略を模式的に示した図である。It is the figure which showed typically the outline of a structure of the film-forming apparatus which concerns on 1st Embodiment. 図１の成膜装置における処理容器内の構成の概略を模式的に示した断面図である。It is sectional drawing which showed the outline of the structure inside the processing container in the film-forming apparatus of FIG. 1 typically. 従来の成膜装置における処理容器内の構成の概略を模式的に示した断面図である。It is sectional drawing which showed the outline of the structure inside the processing container in the conventional film-forming apparatus typically. 本発明者らが行った不純物濃度分布に関する評価試験の結果を示す図である。It is a figure which shows the result of the evaluation test regarding the impurity concentration distribution performed by the present inventors. 本発明者らが行った欠陥分布に関する評価試験の結果を示す図である。It is a figure which shows the result of the evaluation test regarding the defect distribution which the present inventors performed. 本発明者らが行った欠陥分布に関する評価試験の結果を示す図である。It is a figure which shows the result of the evaluation test regarding the defect distribution which the present inventors performed. 図２のサセプタを基準とした、模式的な温度分布と模式的な不純物濃度分布とを重ね合わせて示す図である。FIG. 3 is a diagram in which a schematic temperature distribution and a schematic impurity concentration distribution are superimposed on each other with the susceptor of FIG. 2 as a reference. 確認試験の結果を示す図である。It is a figure which shows the result of a confirmation test. 第２実施形態に係る成膜装置の構成の概略を説明するための模式断面図である。It is a schematic cross section for explaining the outline of the composition of the film deposition system concerning a 2nd embodiment. 第３実施形態に係る成膜装置の構成の概略を説明するための模式断面図である。It is a schematic cross section for explaining the outline of the composition of the film deposition system concerning a 3rd embodiment.
　近年、半導体パワーデバイスといった電子デバイスに、ＳｉＣが用いられるようになっている。このような電子デバイスの製造では、単結晶の基板上に基板結晶と同じ方位関係を有する膜を成長させるエピタキシャル成長によって、ＳｉＣ膜が成膜される。 Recently, SiC has been used for electronic devices such as semiconductor power devices. In manufacturing such an electronic device, a SiC film is formed on a single crystal substrate by epitaxial growth in which a film having the same orientation as that of the substrate crystal is grown.
　ところで、ＳｉＣ膜の成膜装置では、成膜用に処理ガスを用いており、処理ガスの供給方式として、ダウンフロー方式とサイドフロー方式とがある。ダウンフロー方式では、処理ガスが基板表面に対して衝突するように上方から供給される。サイドフロー方式では、処理ガスが基板表面に沿って流れるように側方から供給される。特許文献１に開示の成膜装置は、回転ステージをその内部空間に収容するよう構成されたサセプタの当該内部空間において、回転ステージの外側から当該回転ステージの中心軸線に直交する方向に沿って処理ガスを供給している。つまり、特許文献１に開示の成膜装置は、処理ガスの供給方式としてサイドフロー方式を採用している。 By the way, in a film forming apparatus for a SiC film, a processing gas is used for film formation, and there are a downflow method and a side flow method as a method of supplying the processing gas. In the downflow method, the processing gas is supplied from above so as to collide with the substrate surface. In the side flow method, the processing gas is supplied from the side so as to flow along the surface of the substrate. In the film forming apparatus disclosed in Patent Document 1, in the internal space of the susceptor configured to accommodate the rotary stage in the internal space, processing is performed from the outside of the rotary stage along a direction orthogonal to the central axis of the rotary stage. Supplying gas. That is, the film forming apparatus disclosed in Patent Document 1 employs the side flow method as the processing gas supply method.
　また、サイドフロー方式を採用した特許文献１に開示の成膜装置では、前述のように、回転ステージ上のウェハの面内における温度のバラツキを低減させていた。これは、ＳｉＣ膜内の不純物濃度のウェハの面内におけるバラツキを抑制するためである。 Further, in the film forming apparatus disclosed in Patent Document 1 that employs the side flow method, as described above, the temperature variation in the plane of the wafer on the rotary stage is reduced. This is to suppress the variation in the impurity concentration in the SiC film within the surface of the wafer.
　しかし、サイドフロー方式を採用した成膜装置により形成されたＳｉＣ膜には、不純物濃度のウェハの面内におけるバラツキについて、更に改善されることが好ましい。例えば、本発明者らが後述のように鋭意調査したところによれば、サイドフロー方式を採用した従来の成膜装置により形成されたＳｉＣ膜では、上流側であり回転ステージの外周部に近い領域に位置する部分において、不純物濃度が高くなる。
　さらに、ハロゲン元素含有ガスを用いた成膜においても、上記外周部における不純物濃度の立ち上がりが顕著である。また、ハロゲン元素含有ガスを用いた成膜では、欠陥が生じやすくなっている。なお、ハロゲン元素含有ガスを用いた成膜とは、原料ガスとしてＳｉ含有ガス（シランガス等）と共にハロゲン元素含有ガス（塩化水素ガス等）を供給する成膜である。原料ガスとしてケイ素（Ｓｉ）とハロゲン元素の両方を含有するガス（ジクロロシランやトリクロロシラン等）を供給する成膜も、ハロゲン元素含有ガスを用いた成膜に含まれる。 However, in the SiC film formed by the film forming apparatus adopting the side flow method, it is preferable that the variation in the impurity concentration within the surface of the wafer is further improved. For example, according to the inventors of the present invention, as a result of diligent investigations, the SiC film formed by the conventional film forming apparatus adopting the side flow method is located on the upstream side and near the outer peripheral portion of the rotary stage. The impurity concentration becomes high in the portion located at.
Further, even in the film formation using the halogen element-containing gas, the rising of the impurity concentration in the outer peripheral portion is remarkable. Further, defects are likely to occur in film formation using a gas containing a halogen element. Note that the film formation using the halogen element-containing gas is film formation in which the halogen element-containing gas (hydrogen chloride gas or the like) is supplied together with the Si-containing gas (silane gas or the like) as a source gas. Film formation in which a gas containing both silicon (Si) and a halogen element (dichlorosilane, trichlorosilane, etc.) is supplied as a source gas is also included in the film formation using the halogen element-containing gas.
　そこで、本開示にかかる技術は、サイドフロー方式で原料ガスが供給される成膜装置及び成膜方法によって形成されるＳｉＣ膜の品質を向上させる。 Therefore, the technology according to the present disclosure improves the quality of the SiC film formed by the film forming apparatus and the film forming method in which the source gas is supplied by the side flow method.
　以下、本実施形態にかかる成膜装置及び成膜方法を、図面を参照して説明する。なお、本明細書及び図面において、実質的に同一の機能構成を有する要素については、同一の符号を付することにより重複説明を省略する。 The film forming apparatus and the film forming method according to this embodiment will be described below with reference to the drawings. In the present specification and the drawings, elements having substantially the same functional configuration are designated by the same reference numerals, and duplicate description will be omitted.
（第１実施形態）
　図１は、第１実施形態に係る成膜装置の構成の概略を模式的に示した図である。
　図１の成膜装置１は、処理ガスの供給方式としてサイドフロー方式を採用するものであり、略直方体状の処理容器１１を備える。
　処理容器１１には、排気ライン１２が接続されており、処理容器１１は、排気ライン１２により所望の減圧状態（圧力）に調整することが可能となっている。排気ライン１２は、処理容器１１に一端が接続される排気管１２ａを有する。排気管１２ａは、排気マニホールド等から成り、処理容器１１側とは反対側にメカニカルブースターポンプ等からなる真空ポンプ１２ｂが接続されている。排気管１２ａにおける処理容器１１と真空ポンプ１２ｂとの間には、ＡＰＣ（自動圧力制御）バルブや比例制御弁等からなる、処理容器１１内の圧力を調整する圧力調整部１２ｃが設けられている。また、処理容器１１には、圧力計１３が設けられており、圧力調整部１２ｃによる処理容器１１内の圧力の調整は、圧力計１３での計測結果に基づいて行われる。 (First embodiment)
FIG. 1 is a diagram schematically showing an outline of the configuration of the film forming apparatus according to the first embodiment.
The film forming apparatus 1 of FIG. 1 adopts a side flow method as a processing gas supply method and includes a substantially rectangular parallelepiped processing container 11.
An exhaust line 12 is connected to the processing container 11, and the processing container 11 can be adjusted to a desired reduced pressure state (pressure) by the exhaust line 12. The exhaust line 12 has an exhaust pipe 12 a whose one end is connected to the processing container 11. The exhaust pipe 12a is composed of an exhaust manifold or the like, and a vacuum pump 12b such as a mechanical booster pump is connected to the side opposite to the processing container 11 side. Between the processing container 11 and the vacuum pump 12b in the exhaust pipe 12a, a pressure adjusting unit 12c including an APC (automatic pressure control) valve, a proportional control valve or the like for adjusting the pressure inside the processing container 11 is provided. .. Further, the processing container 11 is provided with a pressure gauge 13, and the pressure inside the processing container 11 is adjusted by the pressure adjusting unit 12 c based on the measurement result of the pressure gauge 13.
　処理容器１１は、両端に開口部を有する中空の四角柱状の処理容器本体１１ａと、上記開口部を塞ぐように処理容器本体１１ａの両端それぞれに接続されるフランジ１１ｂとを有する。処理容器本体１１ａは、石英等により形成されている。 The processing container 11 has a hollow rectangular columnar processing container body 11a having openings at both ends, and flanges 11b connected to both ends of the processing container body 11a so as to close the opening. The processing container body 11a is made of quartz or the like.
　処理容器本体１１ａの外側には、高周波電源１４ａに接続された誘導コイル１４が設けられている。誘導コイル１４は、処理対象基板を加熱するものであり、例えば、後述のサセプタ３０等を誘導加熱し、誘導加熱されたサセプタ３０からの輻射熱や熱伝導により処理対象基板等を加熱する。
　なお、本実施形態では、誘導コイル１４による誘導加熱は、処理ガスの流れ方向において、単位長さ当たりの加熱量が一定であるものとする。 An induction coil 14 connected to a high frequency power source 14a is provided outside the processing container body 11a. The induction coil 14 heats the processing target substrate. For example, the induction coil 14 induction-heats the susceptor 30 and the like described below, and heats the processing target substrate and the like by radiant heat and heat conduction from the induction-heated susceptor 30.
In the present embodiment, it is assumed that the induction heating by the induction coil 14 has a constant heating amount per unit length in the flow direction of the processing gas.
　処理容器１１内には、ガス供給機構１５により成膜の原料となる原料ガス等が供給されるよう構成されている。ガス供給機構１５は、処理容器１１に接続されるガス供給管１５ａと、該ガス供給管１５ａに接続されるガス供給管１５ｂ１～１５ｂ６とを有する。 A gas supply mechanism 15 is configured to supply a raw material gas, which is a raw material for film formation, into the processing container 11. The gas supply mechanism 15 has a gas supply pipe 15a connected to the processing container 11 and gas supply pipes 15b 1 to 15b 6 connected to the gas supply pipe 15a.
　ガス供給管１５ｂ１～１５ｂ６にはそれぞれ、質量流量コントローラ（ＭＦＣ）１５ｃ１～１５ｃ６とバルブ１５ｄ１～１５ｄ６とが設けられている。
　ガス供給管１５ｂ１には、ガス供給源１５ｅ１が接続され、該供給源１５ｅ１からシラン（ＳｉＨ４）ガスが供給される。同様に、ガスライン１５ｂ２～１５ｂ６にはそれぞれガス供給源１５ｅ２～１５ｅ６が接続され、各ガス供給源１５ｅ２～１５ｅ６からプロパン（Ｃ３Ｈ８）ガス、水素（Ｈ２）ガス、窒素ガス（Ｎ２ガス）、塩化水素（ＨＣｌ）ガス、アルゴン（Ａｒ）ガスが供給される。 The gas supply pipes 15b 1 to 15b 6 are provided with mass flow controllers (MFC) 15c 1 to 15c 6 and valves 15d 1 to 15d 6 , respectively.
A gas supply source 15e 1 is connected to the gas supply pipe 15b 1 , and a silane (SiH 4 ) gas is supplied from the supply source 15e 1 . Similarly, gas supply sources 15e 2 to 15e 6 are connected to the gas lines 15b 2 to 15b 6 , respectively, and propane (C 3 H 8 ) gas and hydrogen (H 2 ) gas are supplied from the gas supply sources 15e 2 to 15e 6. , Nitrogen gas (N 2 gas), hydrogen chloride (HCl) gas, and argon (Ar) gas are supplied.
　処理対象基板としてのＳｉＣ基板上に、エピタキシャル成長によりｎ型のＳｉＣ膜の成膜を行う場合には、成膜のための原料ガスとして、ガス供給管１５ｂ１～１５ｂ５からＳｉＨ４ガス、Ｃ３Ｈ８ガス、Ｈ２ガス、Ｎ２ガス、ＨＣｌガスが処理容器１１に供給される。なお、ｐ型のＳｉＣ膜の成膜のために、ＴＭＡ（トリメチルアルミニウム）ガス用のガス供給源とガス供給管等を設けておいてもよい。
　また、処理容器１１内の構造物に付着した異物を除去する際には、例えば、ガス供給管１５ｂ３、１５ｂ６からＨ２ガス、Ａｒガスのうちの１種が、または、これらのガスが混合されて、処理容器１１に供給される。 When a n-type SiC film is formed by epitaxial growth on a SiC substrate as a processing target substrate, SiH 4 gas, C 3 gas from the gas supply pipes 15b 1 to 15b 5 are used as a source gas for the film formation. The H 8 gas, the H 2 gas, the N 2 gas, and the HCl gas are supplied to the processing container 11. A gas supply source for TMA (trimethylaluminum) gas, a gas supply pipe, and the like may be provided for forming the p-type SiC film.
Further, when removing the foreign matter attached to the structure in the processing container 11, for example, one of the H 2 gas and the Ar gas from the gas supply pipes 15b 3 and 15b 6 or these gases are It is mixed and supplied to the processing container 11.
　また、成膜装置１は制御部５０を備えている。制御部５０は、例えばコンピュータであり、プログラム格納部（図示せず）を有している。プログラム格納部には、ＭＦＣ１５ｃ１～１５ｃ６やバルブ１５ｄ１～１５ｄ６、高周波電源１４ａ、圧力調整部１２ｃ等を制御して成膜処理を行うためのプログラムが格納されている。なお、上記プログラムは、コンピュータに読み取り可能な記憶媒体に記録されていたものであって、当該記憶媒体から制御部５０にインストールされたものであってもよい。 The film forming apparatus 1 also includes a control unit 50. The control unit 50 is, for example, a computer and has a program storage unit (not shown). The program storage unit stores a program for controlling the MFCs 15c 1 to 15c 6 , the valves 15d 1 to 15d 6 , the high frequency power supply 14a, the pressure adjusting unit 12c, and the like to perform the film forming process. The program may be recorded in a computer-readable storage medium, and may be installed in the control unit 50 from the storage medium.
　続いて、処理容器１１内の構成について説明する。図２は、図１の成膜装置１における処理容器１１内の構成の概略を模式的に示した断面図である。
　処理容器１１の内部には、図２に示すように、処理対象基板としてのＳｉＣ基板Ｗ（以下、「基板Ｗ」と省略することがある。）が載置される載置台２０と、載置台２０を回転させると共に該載置台２０を支持する回転軸２１と、が設けられている。また、処理容器１１の内部には、誘導コイル１４による誘導加熱により加熱されるサセプタ３０が設けられている。 Next, the internal structure of the processing container 11 will be described. FIG. 2 is a cross-sectional view schematically showing an outline of the configuration inside the processing container 11 in the film forming apparatus 1 of FIG.
Inside the processing container 11, as shown in FIG. 2, a mounting table 20 on which a SiC substrate W (hereinafter, may be abbreviated as “substrate W”) as a processing target substrate is mounted, and a mounting table. A rotation shaft 21 that rotates the 20 and supports the mounting table 20 is provided. A susceptor 30 heated by induction heating by the induction coil 14 is provided inside the processing container 11.
　載置台２０は、サセプタ３０内において、その載置面（図の上面）が水平になるように配置されている。この載置台２０が、回転軸２１を中心に（具体的には、回転軸の中心軸線Ｐ１を中心に）回転することにより、載置台２０に載置された基板Ｗが回転軸２１を中心に回転する。
　載置台２０は、耐熱性が高くかつ誘導加熱による加熱が容易な導電性材料で形成されており、例えば、上面がＳｉＣによりコーティングされたグラファイト製の部材から構成される。 The mounting table 20 is arranged in the susceptor 30 such that the mounting surface (the upper surface in the drawing) is horizontal. By rotating the mounting table 20 about the rotary shaft 21 (specifically, centering on the central axis P1 of the rotary shaft), the substrate W mounted on the mounting table 20 rotates about the rotary shaft 21. Rotate.
The mounting table 20 is formed of a conductive material having high heat resistance and easy to be heated by induction heating, and is composed of, for example, a graphite member whose upper surface is coated with SiC.
　回転軸２１は、その一端が載置台２０の下部中央に接続され、他端が処理容器１１の底部を突き抜けてその下方に至り、回転駆動機構（図示せず）に接続されている。上記回転駆動機構により回転軸２１が回転されることにより、載置台２０が回転する。 The rotary shaft 21 has one end connected to the center of the lower part of the mounting table 20, and the other end penetrating the bottom of the processing container 11 to reach the lower part thereof and connected to a rotary drive mechanism (not shown). When the rotation shaft 21 is rotated by the rotation drive mechanism, the mounting table 20 is rotated.
　サセプタ３０は、載置台２０を収容する内部空間Ｓを有する。また、サセプタ３０は、互いに対向する二つの側面に開口が設けられた直方体状に形成され、一方の側面の開口から処理ガスが供給され、他方の側面の開口から処理ガスが排出される構造となっている。この構造では、サセプタ３０内において、処理ガスが、回転軸２１の中心軸線Ｐ１に対して直交する方向であり載置台２０上の基板Ｗの処理対象面（図の上面）に平行な方向に沿って供給され、排出される。
　なお、サセプタ３０の内部空間Ｓの詳細については後述する。
　サセプタ３０は、耐熱性が高くかつ誘導加熱による加熱が容易な導電性材料で形成されており、例えば、ＳｉＣによりコーティングされたグラファイト製の部材から構成される。 The susceptor 30 has an internal space S that accommodates the mounting table 20. The susceptor 30 is formed in a rectangular parallelepiped shape having openings on two side surfaces facing each other, and the processing gas is supplied from the opening on one side surface and the processing gas is discharged from the opening on the other side surface. Has become. In this structure, in the susceptor 30, the processing gas is in a direction orthogonal to the central axis P1 of the rotating shaft 21 and in a direction parallel to the processing target surface (the upper surface in the drawing) of the substrate W on the mounting table 20. Supplied and discharged.
The details of the internal space S of the susceptor 30 will be described later.
The susceptor 30 is formed of a conductive material having high heat resistance and easy to be heated by induction heating, and is composed of, for example, a graphite member coated with SiC.
　また、サセプタ３０の外周を覆うように断熱材３１が設けられている。断熱材３１は、サセプタ３０と処理容器１１とを断熱するものであり、サセプタ３０と同様な直方体状に形成されている。また、断熱材３１の側面には、サセプタ３０の側面の上述の開口と連通する開口が設けられている。この断熱材３１は、例えば、空隙率が大きい繊維状のカーボン材料を用いて形成される。 Also, a heat insulating material 31 is provided so as to cover the outer periphery of the susceptor 30. The heat insulating material 31 insulates the susceptor 30 and the processing container 11 from each other, and is formed in a rectangular parallelepiped shape similar to the susceptor 30. Further, on the side surface of the heat insulating material 31, an opening communicating with the above-described opening on the side surface of the susceptor 30 is provided. The heat insulating material 31 is formed using, for example, a fibrous carbon material having a large porosity.
　さらに、断熱材３１を覆うように保持部材３２が設けられている。
　保持部材３２は、断熱材３１に覆われたサセプタ３０を収容する空間をその内部に有する本体部３２ａと、サセプタ３０及び断熱材３１の側面の上述の開口を介してサセプタ３０内の内部空間Ｓに通ずる一対の管路３２ｂ１、３２ｂ２とを有する。処理ガスの流れ方向における上流側（以下、「給気側」ということがある。）の管路３２ｂ１は、サセプタ３０と反対側の端部が、ガス供給機構１５側のフランジ１１ｂに接続されている。これにより、ガス供給機構１５からの処理ガスをサセプタ３０内の内部空間Ｓに供給可能となっている。また、処理ガスの流れ方向における下流側（以下、「排気側」ということがある。）の管路３２ｂ２は、サセプタ３０と反対側の端部が、排気ライン１２側のフランジ１１ｂに接続されている。これにより、サセプタ３０内の内部空間Ｓから排気可能となっている。
　この保持部材３２は、例えば石英で形成される。なお、保持部材３２は、柱状の支持部３３を介して処理容器１１の内面に支持されている。 Further, a holding member 32 is provided so as to cover the heat insulating material 31.
The holding member 32 has a main body portion 32a having a space for accommodating the susceptor 30 covered with the heat insulating material 31 therein, and the internal space S in the susceptor 30 through the above-described openings on the side surfaces of the susceptor 30 and the heat insulating material 31. And a pair of conduits 32b 1 and 32b 2 communicating with each other. An upstream end (hereinafter, also referred to as “air supply side”) of the processing gas in the flow direction 32b 1 is connected to the flange 11b on the gas supply mechanism 15 side at the end opposite to the susceptor 30. ing. As a result, the processing gas from the gas supply mechanism 15 can be supplied to the internal space S in the susceptor 30. In addition, the downstream side (hereinafter, also referred to as “exhaust side” in some cases) 32b 2 in the flow direction of the processing gas, the end opposite to the susceptor 30 is connected to the flange 11b on the exhaust line 12 side. ing. As a result, the internal space S inside the susceptor 30 can be exhausted.
The holding member 32 is made of, for example, quartz. The holding member 32 is supported on the inner surface of the processing container 11 via a columnar support portion 33.
　本実施形態では、以上のように構成される処理容器１１内において、さらにサセプタ３０の内部空間Ｓが、載置台空間Ｓ１と予熱空間Ｓ２とを有するように構成されている。 In the present embodiment, the internal space S of the susceptor 30 is further configured to have a mounting table space S1 and a preheating space S2 in the processing container 11 configured as described above.
　載置台空間Ｓ１は、載置台２０が位置する空間である。
　予熱空間Ｓ２は、処理ガスの流れ方向（以下、「ガス流方向」ということがある。）における載置台空間Ｓ１すなわち載置台２０より上流側に位置し、成膜時に載置台空間Ｓ１に供給される処理ガスをサセプタ３０により予熱する空間である。 The mounting table space S1 is a space in which the mounting table 20 is located.
The preheating space S2 is located upstream of the mounting table space S1, that is, the mounting table 20 in the flow direction of the processing gas (hereinafter, also referred to as “gas flow direction”), and is supplied to the mounting table space S1 during film formation. This is a space where the processing gas is preheated by the susceptor 30.
　本実施形態では、サセプタ３０に対して載置台２０の回転軸２１を排気側にオフセットさせることにより、予熱空間Ｓ２が形成されている。より具体的には、載置台２０の回転軸２１の中心軸線Ｐ１が、ガス流方向における、サセプタ３０の中心軸線Ｐ２より下流側に位置することにより、予熱空間Ｓ２が形成されている。 In the present embodiment, the preheating space S2 is formed by offsetting the rotary shaft 21 of the mounting table 20 to the exhaust side with respect to the susceptor 30. More specifically, the preheating space S2 is formed by locating the central axis P1 of the rotating shaft 21 of the mounting table 20 on the downstream side of the central axis P2 of the susceptor 30 in the gas flow direction.
　ところで、サイドフロー方式を採用した従来の成膜装置では、図３に示すように、処理容器１００、載置台１０１、サセプタ１０２それぞれの中心軸線Ｐ１～Ｐ３が一致するのが一般的な構造である。図２の本実施形態の構造は、上記一般的な構造に対し、処理容器１１の中心軸線Ｐ３に対して、載置台２０の中心軸線Ｐ１の位置を、排気側にオフセットさせ、そのオフセットさせた分だけサセプタ３０を排気側に伸ばした構造と言うことができる。したがって、本実施形態の構造は、ガス供給機構１５側のフランジ１１ｂからサセプタ３０までの距離より、排気ライン１２側のフランジ１１ｂからサセプタ３０までの距離の方が短い構造である。 By the way, in a conventional film forming apparatus adopting the side-flow method, as shown in FIG. 3, the central axes P1 to P3 of the processing container 100, the mounting table 101, and the susceptor 102 are generally aligned with each other. .. In the structure of the present embodiment of FIG. 2, the position of the central axis P1 of the mounting table 20 is offset to the exhaust side with respect to the central axis P3 of the processing container 11 with respect to the general structure described above, and the position is offset. It can be said that the structure is such that the susceptor 30 is extended to the exhaust side by an amount. Therefore, in the structure of the present embodiment, the distance from the flange 11b on the exhaust line 12 side to the susceptor 30 is shorter than the distance from the flange 11b on the gas supply mechanism 15 side to the susceptor 30.
　なお、予熱空間Ｓ２には、載置台２０の給気側端と、サセプタ３０の給気側内周端との間を塞ぐように、回り込み防止部材３４が設けられている。回り込み防止部材３４は、処理ガスが載置台２０の裏側等に回り込むのを防止するためのものである。この回り込み防止部材３４は、耐熱性が高い材料で形成されており、例えば、上面がＳｉＣによりコーティングされたグラファイト製の部材から構成される。 A wraparound prevention member 34 is provided in the preheating space S2 so as to close the space between the air supply side end of the mounting table 20 and the air supply side inner peripheral end of the susceptor 30. The wraparound prevention member 34 is for preventing the processing gas from wrapping around to the back side of the mounting table 20 or the like. The wraparound prevention member 34 is formed of a material having high heat resistance, and is formed of, for example, a graphite member whose upper surface is coated with SiC.
　次に、成膜装置１を用いた、成膜処理を含む基板処理を説明する。
　まず、基板Ｗが、処理容器１１内に搬入される（ステップ１）。具体的には、基板Ｗを、成膜装置１の外部の搬送手段（図示せず）によって、成膜装置１の外部からゲートバルブ（図示せず）及び給気側の管路３２ｂ１を介して処理容器１１のサセプタ３０の内部空間Ｓに搬入させ、載置台２０の上方に位置させる。次に、昇降部（図示せず）を上昇させ、当該昇降部により基板Ｗを支持させる。次いで、上記搬送手段を処理容器１１内から退避させると共に、昇降部を下降させ、これにより、基板Ｗが載置台２０上に載置される。なお、基板Ｗは、載置台２０上に直接ではなく、円板状部材であるホルダ（図示せず）を介して載置されてもよい。 Next, substrate processing including film forming processing using the film forming apparatus 1 will be described.
First, the substrate W is loaded into the processing container 11 (step 1). Specifically, the substrate W is transferred from the outside of the film forming apparatus 1 via a gate valve (not shown) and the gas supply side conduit 32b 1 by a transfer means (not shown) outside the film forming apparatus 1. The processing container 11 is loaded into the internal space S of the susceptor 30 and is positioned above the mounting table 20. Next, the elevating part (not shown) is raised, and the substrate W is supported by the elevating part. Next, the transport means is retracted from the processing container 11, and the elevating unit is lowered, so that the substrate W is placed on the mounting table 20. The substrate W may be placed not directly on the mounting table 20 but via a holder (not shown) that is a disk-shaped member.
　基板Ｗの搬入後、ガス供給機構１５からの処理ガスとしての原料ガスとキャリアガスを、内部空間Ｓ内において基板Ｗの処理対象面に沿って流れるように供給させる。それと共に、高周波電源１４ａからの高周波電力を、誘導コイル１４に印加させる。これにより、基板Ｗが加熱され、エピタキシャル成長により基板Ｗ上にｎ型のＳｉＣ膜が形成される（ステップ２）。具体的には、バルブ１５ｄ１～１５ｄ５を開状態にさせ、ＭＦＣ１５ｃ１～１５ｃ５で流量を調整させ、処理容器１１内の内部空間ＳにＳｉＨ４ガス、Ｃ３Ｈ８ガス、Ｈ２ガス、Ｎ２ガス、ＨＣｌガスを供給させる。また、高周波電源１４ａから誘導コイル１４に高周波電力を印加させ、ホルダ、載置台２０、サセプタ３０を誘導加熱させ、これらからの輻射や熱伝導により基板Ｗを加熱させる。この成膜の過程において、載置台空間Ｓ１へ供給される処理ガスは、予熱空間Ｓ２で加熱されたものである。 After the substrate W is loaded, the source gas and the carrier gas as the processing gas from the gas supply mechanism 15 are supplied so as to flow along the surface to be processed of the substrate W in the internal space S. At the same time, the high frequency power from the high frequency power supply 14 a is applied to the induction coil 14. As a result, the substrate W is heated, and an n-type SiC film is formed on the substrate W by epitaxial growth (step 2). Specifically, the valves 15d 1 to 15d 5 are opened, the flow rate is adjusted by the MFCs 15c 1 to 15c 5 , and SiH 4 gas, C 3 H 8 gas, and H 2 gas are introduced into the internal space S in the processing container 11. , N 2 gas, and HCl gas are supplied. Further, high frequency power is applied to the induction coil 14 from the high frequency power source 14a to inductively heat the holder, the mounting table 20, and the susceptor 30, and the substrate W is heated by radiation and heat conduction from these. In the film forming process, the processing gas supplied to the mounting table space S1 is heated in the preheating space S2.
　なお、成膜中において、処理容器１１内の圧力は例えば１０Ｔｏｒｒ～６００Ｔｏｒｒであり、基板Ｗの温度は例えば１５００℃～１７００℃である。また、本例では、ＳｉＨ４ガスと共にＨＣｌガスを供給しているが、ＨＣｌガスの供給は省略してもよい。ただし、ＨＣｌガスを供給することで、塩素（Ｃｌ）によるＳｉＣｌ２の形成により気層でのＳｉ－Ｓｉ結合の形成が抑制されるため、高速成長が可能である。また、ＨＣｌガスを供給することで、ＨＣｌによるエッチング効果により処理容器１１内等の副生成物生成の抑制ができるため、副生成物除去処理に要する時間を短縮できるので、生産性を向上させることができる。なお、ＨＣｌガスに代えて、フッ化水素ガスやジクロロシラン（ＳｉＨ２Ｃｌ２）ガス等の他のハロゲン含有ガスを供給するようにしてもよい。 During the film formation, the pressure inside the processing container 11 is, for example, 10 Torr to 600 Torr, and the temperature of the substrate W is, for example, 1500° C. to 1700° C. Further, in this example, the HCl gas is supplied together with the SiH 4 gas, but the supply of the HCl gas may be omitted. However, the supply of HCl gas suppresses the formation of Si—Si bonds in the vapor layer due to the formation of SiCl 2 by chlorine (Cl), so that high-speed growth is possible. Further, by supplying the HCl gas, it is possible to suppress the generation of by-products in the processing container 11 or the like due to the etching effect of HCl, so that the time required for the by-product removal processing can be shortened, so that the productivity is improved. You can Instead of HCl gas, other halogen-containing gas such as hydrogen fluoride gas or dichlorosilane (SiH 2 Cl 2 ) gas may be supplied.
　成膜完了後、基板Ｗが処理容器１１から搬出される（ステップ３）。具体的には、バルブ１５ｄ１～１５ｄ５を閉状態にさせ、原料ガスとキャリアガスの供給を停止させた後、昇降部を上昇させ、基板Ｗを上昇させる。そして、成膜装置１の外部の搬送手段を、ゲートバルブ及び管路３２ｂ１を介して処理容器１１内に挿入させ、基板Ｗの下方に位置させる。その後、昇降部を下降させることで、基板Ｗが昇降部から上記搬送手段に受け渡され、該搬送手段を処理容器１１から退避させることにより、基板Ｗが処理容器１１から搬出される。なお、基板Ｗの搬出中、誘導コイル１４への高周波電力の供給を遮断してもよいが、次工程において最適な載置台２０及びサセプタ３０の温度になるよう制御しながら誘導コイル１４へ高周波電力を供給することが好ましい。 After the film formation is completed, the substrate W is unloaded from the processing container 11 (step 3). Specifically, the valves 15d 1 to 15d 5 are closed, the supply of the source gas and the carrier gas is stopped, and then the elevating part is raised to raise the substrate W. Then, the transfer means outside the film forming apparatus 1 is inserted into the processing container 11 via the gate valve and the conduit 32b 1 and positioned below the substrate W. After that, the substrate W is transferred from the elevating unit to the transfer means by lowering the elevating unit, and the substrate W is unloaded from the processing container 11 by retracting the transfer unit from the processing container 11. Although the supply of the high frequency power to the induction coil 14 may be interrupted while the substrate W is being carried out, the high frequency power is supplied to the induction coil 14 while controlling the temperature of the mounting table 20 and the susceptor 30 to be optimum in the next process. Is preferably supplied.
　基板Ｗの搬出後、ステップ１に処理が戻され、別の基板Ｗが処理容器１１内に搬入され、ステップ１～ステップ３の処理が繰り返される。 After the substrate W is unloaded, the process is returned to step 1, another substrate W is loaded into the processing container 11, and the processes of steps 1 to 3 are repeated.
　続いて、本実施形態の作用及び効果を説明する。
　サイドフロー方式を採用した成膜装置として、図３に示した従来の一般的な構造を有するものを用いて形成されたｎ型ＳｉＣ膜では、載置台１０１の外周部に近い領域に位置する部分において、不純物濃度が高くなっていた。特に、ハロゲン元素含有ガスを用いた成膜では、その傾向が顕著であった。なお、以下では、「従来の成膜装置」とは、図３の構造を有する成膜装置であるものとする。また、ＳｉＣ膜とは、別途記載がなければ「ｎ型ＳｉＣ膜」であるものとする。 Next, the operation and effect of this embodiment will be described.
In the n-type SiC film formed by using the film forming apparatus adopting the side flow method and having the conventional general structure shown in FIG. 3, a portion located in a region close to the outer peripheral portion of the mounting table 101. In, the impurity concentration was high. In particular, this tendency was remarkable in film formation using a gas containing a halogen element. In the following, the “conventional film forming apparatus” is a film forming apparatus having the structure of FIG. In addition, the SiC film is an “n-type SiC film” unless otherwise specified.
　上述の不純物濃度の不均一性を解消するべく本発明者らが行った評価試験のうちの１つの結果が図４に示されている。図４には、従来の成膜装置を用いて成膜されたＳｉＣ膜の不純物濃度分布が示されている。この評価試験では、処理ガスとしてＳｉＨ４ガス、Ｃ３Ｈ８ガス、Ｈ２ガス、Ｎ２ガスを供給した成膜（以下、「通常エピ」という。）と、処理ガスとしてさらにＳｉＨ２Ｃｌ２ガスを追加供給した成膜（「ハロゲンエピ」という。）とを行った。なお、通常エピとハロゲンエピにおいて、処理ガス中のＳｉ濃度が同じになるように、ガス流量を調整した。また、この評価試験に係る成膜では、３枚の直径約７５ｍｍの基板Ｗが、直径約３００ｍｍのホルダを介して、直径約３４５ｍｍの載置台１０１に載置され、載置台１０１の回転は行われなかった。なお、図４の横軸は、ホルダの給気側端部からの距離、縦軸は不純物濃度としての窒素（Ｎ）濃度を示している。 FIG. 4 shows the result of one of the evaluation tests conducted by the present inventors in order to eliminate the above-mentioned non-uniformity of impurity concentration. FIG. 4 shows the impurity concentration distribution of the SiC film formed by using the conventional film forming apparatus. In this evaluation test, a film was formed by supplying SiH 4 gas, C 3 H 8 gas, H 2 gas, and N 2 gas as processing gas (hereinafter referred to as “normal epi”), and SiH 2 Cl 2 as processing gas. The film formation with additional supply of gas (referred to as "halogen epi") was performed. The gas flow rate was adjusted so that the Si concentration in the processing gas was the same between the normal epi and the halogen epi. Further, in the film formation according to this evaluation test, three substrates W having a diameter of about 75 mm are mounted on the mounting table 101 having a diameter of about 345 mm via a holder having a diameter of about 300 mm, and the mounting table 101 is rotated. I didn't understand. The horizontal axis in FIG. 4 represents the distance from the air supply side end of the holder, and the vertical axis represents the nitrogen (N) concentration as the impurity concentration.
　図４に示すように、通常エピの場合もハロゲンエピの場合も、ＳｉＣ膜の不純物濃度は、給気側端部で最も高く、ガス流れ方向に沿って低下し、ホルダの直径の１／３の部分を過ぎたあたりから、ガス流れ方向に沿って再び増加している。
　載置台１０１を回転させないときの成膜でこのような不純物濃度の分布が生ずため、載置台１０１を回転させて形成されたＳｉＣ膜では、載置台１０１の外周部に近い領域に位置する部分において、不純物濃度が高くなるものと考えられる。 As shown in FIG. 4, in both the normal epi and the halogen epi, the impurity concentration of the SiC film is highest at the end on the air supply side, decreases along the gas flow direction, and is 1/3 of the diameter of the holder. After passing the part of, it increases again along the gas flow direction.
Since such an impurity concentration distribution does not occur in film formation when the mounting table 101 is not rotated, in the SiC film formed by rotating the mounting table 101, a portion located in a region near the outer periphery of the mounting table 101 is formed. It is considered that the impurity concentration becomes high.
　図４に示すような不純物濃度分布の不均一性は、以下の理由から生じるものと推察される。すなわち、従来の成膜装置では、供給された原料ガスはサセプタ１０２内を通過する際に急激に加熱される。したがって、原料ガスのガス温度は、給気側が低温であり排気側に向かって温度が上昇する。したがって、８００℃付近から前駆体に分解するとされるＣ３Ｈ８の分解量は給気側で少なく、排気側に向かって増加していく。一方で、ＳｉＨ４は４００℃程度の低温から前駆体に分解される。そのため、給気側では、雰囲気中の前駆体におけるＳｉ原子の数に対する同前駆体における炭素（Ｃ）原子の数の比（Ｃ／Ｓｉ比）が非常に低いため、後述のサイトコンペティション効果により、Ｎの膜内への取り込み量が多くなる。また、排気側に向かうと、サセプタ１０２の内壁との反応等によりＳｉが消費されることによりＳｉ濃度は減少するのに対し、Ｃ３Ｈ８の分解量は前述のように増加するため、Ｃ／Ｓｉ比は高くなる。その結果、Ｎの取り込みは減少してくる。そして、排気側に向かうにつれ、雰囲気中のＣにかかる前駆体であるＣ２Ｈ２の濃度は飽和する一方で、温度上昇に伴いＮ２分解量は増加するため、Ｎの取り込み量は再び増加する。その結果、上述のような不純物濃度分布の不均一性が生じていると推察される。 It is assumed that the non-uniformity of the impurity concentration distribution as shown in FIG. 4 occurs due to the following reasons. That is, in the conventional film forming apparatus, the supplied source gas is rapidly heated when passing through the susceptor 102. Therefore, the gas temperature of the raw material gas is low on the supply side and increases toward the exhaust side. Therefore, the amount of C 3 H 8 decomposed into a precursor from around 800° C. is small on the air supply side and increases toward the exhaust side. On the other hand, SiH 4 is decomposed into a precursor from a low temperature of about 400°C. Therefore, on the air supply side, the ratio of the number of carbon (C) atoms in the precursor to the number of Si atoms in the precursor in the atmosphere (C/Si ratio) is very low. The amount of N incorporated into the film increases. On the exhaust side, the Si concentration decreases due to the consumption of Si due to the reaction with the inner wall of the susceptor 102 and the like, whereas the decomposition amount of C 3 H 8 increases as described above. The /Si ratio becomes higher. As a result, N uptake is reduced. Then, as it goes toward the exhaust side, the concentration of C 2 H 2 which is a precursor of C in the atmosphere is saturated, while the amount of N 2 decomposed increases as the temperature rises, so the amount of N taken up again increases. To do. As a result, it is presumed that the non-uniformity of the impurity concentration distribution as described above occurs.
　この推察結果によれば、給気側において処理ガスの温度を高くしＣ３Ｈ８の分解量を多くして給気側の不純物濃度を下げるために、サセプタ１０２による加熱量を大きくすると、排気側の処理ガスの温度も高くなり、排気側においてＮ２の分解量が多くなり不純物濃度が高くなってしまう。また、排気側の処理ガスの温度を低くしＮ２の分解量を少なくし排気側の不純物濃度を下げるために、サセプタ１０２による加熱量を小さくすると、給気側の処理ガスの温度も低くなる。その結果、給気側において、Ｃ３Ｈ８の分解量が少なくなり、Ｎの膜内への取り込み量が多くなるため、不純物濃度が高くなってしまう。
　このように、従来の成膜装置では、不純物濃度の最適化のための条件出しが難しい。 According to this estimation result, when the temperature of the processing gas is increased on the air supply side to increase the decomposition amount of C 3 H 8 to lower the impurity concentration on the air supply side, the heating amount by the susceptor 102 is increased, the exhaust gas is increased. The temperature of the processing gas on the side is also increased, the amount of N 2 decomposed on the exhaust side is increased, and the impurity concentration is increased. Further, if the heating amount by the susceptor 102 is reduced in order to lower the temperature of the processing gas on the exhaust side to reduce the decomposition amount of N 2 and lower the impurity concentration on the exhaust side, the temperature of the processing gas on the air supply side also decreases. .. As a result, on the air supply side, the amount of decomposition of C 3 H 8 decreases, and the amount of N incorporated into the film increases, so that the impurity concentration increases.
As described above, in the conventional film forming apparatus, it is difficult to set the conditions for optimizing the impurity concentration.
　さらに、従来の成膜装置において、サセプタ１０２による加熱量を大きくすると、以下に説明するように欠陥の問題がある。 Further, in the conventional film forming apparatus, when the heating amount by the susceptor 102 is increased, there is a problem of defects as described below.
　図５及び図６は、図４の結果が得られた評価試験で成膜したＳｉＣ膜の表面の欠陥マップを示す図であり、図５は通常エピで得られた膜表面について示し、図６はハロゲンエピで得られた膜表面について示している。また、図５及び図６では、ガス流れ方向に沿って欠陥マップを示している。例えば、図の上側に位置する欠陥マップの上部は、給気側に載置された基板の給気側端部に相当し、図の下側に位置する欠陥マップの下部は、排気側に載置された基板の排気側端部に相当する。 5 and 6 are diagrams showing a defect map of the surface of the SiC film formed in the evaluation test in which the results of FIG. 4 are obtained, and FIG. 5 shows the film surface obtained by the normal epitaxy, and FIG. Indicates the film surface obtained by halogen epitaxy. 5 and 6, defect maps are shown along the gas flow direction. For example, the upper part of the defect map located on the upper side of the figure corresponds to the air supply side end of the substrate placed on the air supply side, and the lower part of the defect map located on the lower side of the figure is mounted on the exhaust side. It corresponds to the exhaust side end of the placed substrate.
　図５に示すように、通常エピの表面では、給気側の一部でのみ、欠陥が多い領域Ｒ１が存在するが、大部分は欠陥の少ない領域である。
　それに対し、ハロゲンエピの表面では、図６に示すように、欠陥が多い領域Ｒ２が、給気側の一部分だけでなく、ホルダすなわち載置台１０１の中心付近に相当する部分から排気側端部にかけて存在し、広範囲を占めている。なお、給気側の欠陥は、Ｓｉが凝集したＳｉドロップレットに起因するものが主であり、排気側は三角欠陥等の結晶欠陥が主である。 As shown in FIG. 5, on the surface of the normal epi, the region R1 with many defects exists only in a part on the air supply side, but most of the region R1 has few defects.
On the other hand, on the surface of the halogen epi, as shown in FIG. 6, the region R2 having many defects is not limited to a part on the air supply side, but extends from the part corresponding to the center of the holder or the mounting table 101 to the end on the exhaust side. Exists and occupies a wide area. The defects on the air supply side are mainly caused by Si droplets in which Si is aggregated, and the defects on the exhaust side are mainly crystal defects such as triangular defects.
　また、本発明者らが光学顕微鏡を用いて確認したところによれば、ハロゲンエピの表面は、排気側に向かうにつれて粗さが大きくなっていた。 According to the present inventors' confirmation using an optical microscope, the surface of the halogen epi was roughened toward the exhaust side.
　ハロゲンエピの表面に多くの欠陥が生じる理由としては、上述の光学顕微鏡での観察結果も踏まえれば、以下の理由が推察される。すなわち、上記欠陥は、排気側の高温領域におけるＳｉＨ２Ｃｌ２ガスによるエッチングで生じるエッチピットに由来すると推察される。具体的には、処理ガスが高温となる排気側で過剰に活性化したＳｉＨ２Ｃｌ２ガスが基板Ｗの表面にダメージを与え、そのダメージが与えられた部分に成長した結晶に欠陥が導入されたものと推察される。
　この推察結果によれば、従来の成膜装置において、不純物濃度分布の均一性の改善のためにサセプタ１０２による加熱量を大きくし処理ガスの温度を上げると、ハロゲンエピではエッチピット由来の欠陥が多く生じてしまう。 The reason why many defects are generated on the surface of the halogen epi is supposed to be as follows, in consideration of the observation result with the above-mentioned optical microscope. That is, it is presumed that the above-mentioned defects are derived from the etch pits generated by the etching with the SiH 2 Cl 2 gas in the high temperature region on the exhaust side. Specifically, the SiH 2 Cl 2 gas excessively activated on the exhaust side where the processing gas has a high temperature damages the surface of the substrate W, and defects are introduced into the grown crystal in the damaged part. It is speculated that
According to this estimation result, in the conventional film forming apparatus, when the heating amount by the susceptor 102 is increased and the temperature of the processing gas is increased in order to improve the uniformity of the impurity concentration distribution, the defects caused by the etch pits are generated in the halogen epi. Many occur.
　そこで、本実施形態では、サセプタ３０の内部空間における、基板Ｗの載置台空間Ｓ１の給気側に予熱空間Ｓ２を設け、載置台空間Ｓ１に供給する処理ガスをこの予熱空間Ｓ２で予熱している。本実施形態と同様にサイドフロー方式を採用するが本実施形態とは異なり予熱空間Ｓ２を有していない従来の成膜装置では、ガス流れ方向に沿って処理ガスの温度が上昇してしまう。それに対し、本実施形態では、予熱空間Ｓ２を設けているため、載置台空間Ｓ１における排気側の処理ガスの温度上昇を抑えながら、給気側の処理ガスの温度を従来の成膜装置より上げることができる。例えば、ガス流方向にかかる単位長さ当たりの誘導加熱量を下げ、且つ、予熱空間Ｓ２で予熱を行うことにより、載置台空間Ｓ１における排気側の処理ガスの温度上昇を抑えながら、給気側の処理ガスの温度を従来の成膜装置より上げることができる。また、この際、予熱空間Ｓ２のガス流方向にかかる長さを大きくすれば、載置台空間Ｓ１における排気側の処理ガスの温度を下げながら、給気側の処理ガスの温度を上げることができる。 Therefore, in the present embodiment, a preheating space S2 is provided on the supply side of the mounting table space S1 of the substrate W in the internal space of the susceptor 30, and the processing gas supplied to the mounting table space S1 is preheated in the preheating space S2. There is. In the conventional film forming apparatus that employs the side-flow method as in the present embodiment but does not have the preheating space S2 unlike the present embodiment, the temperature of the processing gas rises along the gas flow direction. On the other hand, in the present embodiment, since the preheating space S2 is provided, the temperature of the process gas on the air supply side is raised as compared with the conventional film forming apparatus while suppressing the temperature rise of the process gas on the exhaust side in the mounting table space S1. be able to. For example, by reducing the amount of induction heating per unit length applied in the gas flow direction and preheating in the preheating space S2, the temperature rise of the processing gas on the exhaust side in the mounting table space S1 can be suppressed and the supply side can be reduced. The temperature of the processing gas can be raised more than that of the conventional film forming apparatus. Further, at this time, if the length of the preheating space S2 in the gas flow direction is increased, the temperature of the processing gas on the exhaust side in the mounting table space S1 can be lowered while the temperature of the processing gas on the supply side can be increased. ..
　図７は、サセプタ３０を基準とした、模式的な温度分布と模式的な不純物濃度分布とを重ね合わせて示す図である。
　図７において、実線は載置台２０を回転させない場合の処理ガスの温度分布、点線は、載置台２０を回転させた場合の処理ガスの温度分布の温度分布を示す。また、仮想線は、不純物濃度分布を示し、具体的には、ガス流方向にかかる位置毎に、成膜の際に当該位置で取り込まれ得る不純物としてのＮの量を示している。図中、Ａ１は、サセプタ３０の給気側端を示し、Ａ２は、従来の成膜装置における載置台空間の給気側端に相当する位置を示し、Ａ３は、本実施形態における載置台空間Ｓ１の給気側端を示す。また、Ａ４は、従来の成膜装置における載置台空間の排気側端に相当する位置を示し、Ａ５は、本実施形態における載置台空間Ｓ１の排気側端を示す。 FIG. 7 is a diagram showing a schematic temperature distribution and a schematic impurity concentration distribution with the susceptor 30 as a reference in an overlapping manner.
In FIG. 7, the solid line shows the temperature distribution of the processing gas when the mounting table 20 is not rotated, and the dotted line shows the temperature distribution of the processing gas temperature distribution when the mounting table 20 is rotated. Further, the imaginary line shows the impurity concentration distribution, and specifically shows the amount of N as an impurity that can be taken in at the position during film formation for each position in the gas flow direction. In the figure, A1 indicates the air supply side end of the susceptor 30, A2 indicates the position corresponding to the air supply side end of the mounting table space in the conventional film forming apparatus, and A3 indicates the mounting table space in the present embodiment. The air supply side end of S1 is shown. A4 indicates a position corresponding to the exhaust side end of the mounting table space in the conventional film forming apparatus, and A5 indicates the exhaust side end of the mounting table space S1 in the present embodiment.
　本実施形態では、上述のように予熱空間Ｓ２を設けている。言い換えれば、従来の成膜装置における載置台空間の給気側端に相当する位置Ａ２より、本実施形態における載置台空間Ｓ１の給気側端Ａ３の方が、サセプタ３０の給気側端Ａ１から遠い位置にある。そのため、本実施形態では、載置台空間Ｓ１の給気側端Ａ３においても、処理ガスの温度が高いため、サイトコンペティション効果により取り込まれるＮの量を減らすことができる。したがって、載置台空間Ｓ１の給気側端で成膜されるＳｉＣ膜の不純物濃度を下げることができる。これにより、載置台空間Ｓ１内においては、給気側で窒素取り込み量が少なく、排気側に向けて徐々に窒素取り込み量が増えていくことになる。そのため、成膜の際に載置台２０を回転させることにより、不純物濃度が面内で均一なＳｉＣ膜を得ることができる。つまり、ＳｉＣ膜の品質を向上させることができる。
　なお、サイトコンペティションとは、ＳｉＣ膜へのドーパントの取り込みにおいてＮはＣサイトを置換し、アルミニウム（Ａｌ）はＳｉサイトを置換することから、表面上でＣもしくはＳｉとドーパントの競合が生じ、ドーパントの取り込みに影響が出ることをいう。例えば、低Ｃ／Ｓｉ比の場合、Ｎと競合するＣが少ないことから高Ｎ濃度となる。 In this embodiment, the preheating space S2 is provided as described above. In other words, the air supply side end A1 of the susceptor 30 is closer to the air supply side end A3 of the mounting table space S1 in this embodiment than to the position A2 corresponding to the air supply side end of the mounting table space in the conventional film forming apparatus. It is located far from. Therefore, in this embodiment, since the temperature of the processing gas is high even at the air supply side end A3 of the mounting table space S1, it is possible to reduce the amount of N taken in by the site competition effect. Therefore, it is possible to reduce the impurity concentration of the SiC film formed at the air supply side end of the mounting table space S1. As a result, in the mounting table space S1, the nitrogen intake amount is small on the air supply side and gradually increases toward the exhaust side. Therefore, by rotating the mounting table 20 during film formation, it is possible to obtain a SiC film having an in-plane uniform impurity concentration. That is, the quality of the SiC film can be improved.
Note that the site competition means that, in the incorporation of the dopant into the SiC film, N replaces the C site and aluminum (Al) replaces the Si site. Therefore, competition between C or Si and the dopant occurs on the surface, and the dopant It will affect the uptake of. For example, in the case of a low C/Si ratio, there is a small amount of C that competes with N, resulting in a high N concentration.
　また、前述のように、成膜した際にＮの取り込み量が大きい領域は、サイトコンペティション効果によりＮの取り込み量が大きい給気側の領域と、高温下でのＮ２ガスの熱分解によりＮの取り込み量が大きい排気側の領域と、がある。成膜した際にＮの取り込み量が大きい領域のうち、本実施形態では、上記給気側の領域での成膜を行わずに、上記排気側の領域でのみ成膜を行う。したがって、Ｎの取り込みのモードが絞られるため、不純物濃度を最適化するための条件を容易に得ることができる。 Further, as described above, the region where the amount of N taken up is large when the film is formed, the region on the air supply side where the amount of N taken up is large due to the site competition effect, and the region where N is taken up by the thermal decomposition of N 2 gas at high temperature. There is a region on the exhaust side where a large amount of is taken in. In the present embodiment, of the regions where the amount of N taken in is large at the time of film formation, film formation is not performed in the region on the air supply side, but film formation is performed only in the region on the exhaust side. Therefore, since the mode of capturing N is narrowed down, the condition for optimizing the impurity concentration can be easily obtained.
　さらに、予熱空間Ｓ２を有する構造では、前述のように、載置台空間Ｓ１における排気側の処理ガスの温度を下げながら、給気側の処理ガスの温度を上げることが可能である。したがって、処理ガスの温度の上昇に伴い欠陥が増加するハロゲンエピについて、本実施形態の成膜装置を用いることにより、不純物濃度が面内で均一で、欠陥の少ない高品質なＳｉＣ膜を成膜することができる。 Further, in the structure having the preheating space S2, as described above, it is possible to raise the temperature of the air supply side process gas while lowering the temperature of the exhaust side process gas in the mounting table space S1. Therefore, with respect to the halogen epi where the number of defects increases as the temperature of the processing gas increases, by using the film forming apparatus of this embodiment, a high-quality SiC film having a uniform impurity concentration in the surface and few defects is formed. can do.
　本実施形態は、言い換えると、載置台２０を排気側にオフセットさせて予熱空間Ｓ２を設けることで、以下の点（Ａ）～（Ｃ）を達成している。
（Ａ）高不純物濃度の膜が形成されＳｉドロップレットが生じる給気側の領域での成膜の回避
（Ｂ）載置台空間Ｓ１における給気側での温度上昇による不純物濃度分布及び欠陥の改善
（Ｃ）載置台空間Ｓ１における排気側での温度低下によるハロゲンエピでの欠陥導入防止
　したがって、反応領域が広いサイドフロー方式でも、高速成長化や高スループット化が可能なハロゲンエピによって、高品質のＳｉＣ膜を得ることができる。
　なお、図４では示されていないが、従来の成膜装置を用いたハロゲンエピでは、給気側端の不純物濃度が１０１７ｃｍ－３レベルとなっており、給気端部において不純物濃度の立下りが非常に大きい。本実施形態では、このような領域での成膜を回避している。 In other words, the present embodiment achieves the following points (A) to (C) by offsetting the mounting table 20 to the exhaust side and providing the preheating space S2.
(A) Avoiding film formation in a region on the air supply side where a film with a high impurity concentration is formed and Si droplets are generated (B) Improvement of impurity concentration distribution and defects due to temperature rise on the air supply side in the mounting table space S1 (C) Prevention of introduction of defects in halogen epi due to temperature drop on the exhaust side in the mounting table space S1 Therefore, even in the side-flow method with a wide reaction region, high-quality halogen epi can be achieved by high-speed growth and high throughput. A SiC film can be obtained.
Although not shown in FIG. 4, in the halogen epitaxy using the conventional film forming apparatus, the impurity concentration at the air supply side end is 10 17 cm −3 level, and the impurity concentration at the air supply end is The fall is very large. In this embodiment, film formation in such a region is avoided.
　また、本実施形態の構造は、前述のように、ガス供給機構１５側のフランジ１１ｂからサセプタ３０までの距離より、排気ライン１２側のフランジ１１ｂからサセプタ３０までの距離の方が短い構造である。このように排気ライン１２側のフランジ１１ｂが近いことで、サセプタ３０の加熱に使われるべき誘導磁場がフランジ１１ｂの加熱に使われて、サセプタ３０の排気側の温度が従来よりも低下する。つまり、サイドフロー方式では温度が高くなる傾向にある、載置台空間Ｓ１内の排気側の処理ガスの温度を低下させることができる。そのため、ハロゲンエピの際に、より欠陥の少ない高品質なＳｉＣ膜を成膜することができる。 In addition, as described above, the structure of the present embodiment is a structure in which the distance from the flange 11b on the exhaust line 12 side to the susceptor 30 is shorter than the distance from the flange 11b on the gas supply mechanism 15 side to the susceptor 30. .. Since the flange 11b on the exhaust line 12 side is close in this way, the induction magnetic field that should be used for heating the susceptor 30 is used for heating the flange 11b, and the temperature on the exhaust side of the susceptor 30 becomes lower than in the conventional case. That is, the temperature of the processing gas on the exhaust side in the mounting table space S1, which tends to increase in the side-flow method, can be lowered. Therefore, a high-quality SiC film with fewer defects can be formed during the halogen epitaxy.
（確認試験）
　従来の成膜装置と本実施形態の成膜装置において、ＨＣｌガスによるエッチングを行い、載置台空間における処理ガスの温度を確認する試験を行った。その結果を図８に示す。なお、この試験で用いた成膜装置の載置台２０、１０１は直径３４５ｍｍであり、本実施形態の成膜装置の載置台２０はサセプタ３０の中心から排気側に７０ｍｍオフセットされ、サセプタ３０はそのオフセットの分、従来の成膜装置より長く形成した。また、この試験に係る成膜では、３枚の直径約７５ｍｍの基板Ｗが、直径約３００ｍｍのホルダを介して、載置台２０、１０１に載置され、載置台２０、１０１の回転は行われなかった。 (Confirmation test)
In the conventional film forming apparatus and the film forming apparatus of the present embodiment, a test was carried out to perform etching with HCl gas and confirm the temperature of the processing gas in the mounting table space. The result is shown in FIG. The mounting tables 20 and 101 of the film forming apparatus used in this test have a diameter of 345 mm, and the mounting table 20 of the film forming apparatus of the present embodiment is offset by 70 mm from the center of the susceptor 30 toward the exhaust side. The offset film was formed longer than the conventional film forming apparatus. Further, in the film formation according to this test, three substrates W having a diameter of about 75 mm are mounted on the mounting tables 20 and 101 via the holder having a diameter of about 300 mm, and the mounting tables 20 and 101 are rotated. There wasn't.
　図示するように、従来の成膜装置では、載置台空間における給気側のエッチング量が少なく、排気側のエッチング量が多かった。エッチング量は処理ガスの温度に対応するので、上述の結果を言い換えると、従来の成膜装置では、載置台空間における給気側で処理ガスの温度が低く、排気側で処理ガスの温度が高かった。
　それに対し、本実施形態の装置では、載置台空間Ｓ１における給気側のエッチング量が従来の成膜装置より上がっており、また、載置台空間Ｓ１において、排気側にかけてのエッチング量の上昇率は小さかった。つまり、本実施形態の成膜装置では、給気側の処理ガスの温度が高く、その温度上昇率も抑えることができる。 As shown in the figure, in the conventional film forming apparatus, the etching amount on the air supply side in the mounting table space was small and the etching amount on the exhaust side was large. Since the etching amount corresponds to the temperature of the processing gas, in other words, in the conventional film forming apparatus, the temperature of the processing gas is low on the air supply side and high on the exhaust side in the mounting table space. It was
On the other hand, in the apparatus of this embodiment, the amount of etching on the air supply side in the mounting table space S1 is higher than that in the conventional film forming apparatus, and the rate of increase in the amount of etching toward the exhaust side in the mounting table space S1 is It was small. That is, in the film forming apparatus of the present embodiment, the temperature of the process gas on the air supply side is high and the rate of temperature rise can be suppressed.
　この確認試験の結果からも、本実施形態の成膜装置によれば、載置台空間Ｓ１における排気側の処理ガスの温度を下げながら、給気側の処理ガスの温度を上げることが可能であることが分かる。つまり、本実施形態の成膜装置によれば、不純物濃度が面内で均一なＳｉＣ膜等、高品質なＳｉＣ膜を得ることが可能であることが分かる。 Also from the result of this confirmation test, according to the film forming apparatus of the present embodiment, it is possible to raise the temperature of the supply gas side process gas while lowering the temperature of the exhaust side process gas in the mounting table space S1. I understand. That is, according to the film forming apparatus of the present embodiment, it is possible to obtain a high-quality SiC film such as a SiC film having an in-plane uniform impurity concentration.
　なお、図示するように、本実施形態の成膜装置では、従来の成膜装置より、排気側において、エッチング量が少なく、つまり、処理ガスの温度が低かった。これは、前述のように、排気ライン１２側のフランジ１１ｂが近いことでサセプタ３０の加熱に使われるべき誘導磁場がフランジ１１ｂの加熱に使われてサセプタ３０の排気側の温度が従来よりも低下していること等が影響しているものと考えられる。 As shown in the figure, in the film forming apparatus of the present embodiment, the etching amount was smaller on the exhaust side, that is, the processing gas temperature was lower than that of the conventional film forming apparatus. This is because, as described above, since the flange 11b on the exhaust line 12 side is close, the induction magnetic field that should be used to heat the susceptor 30 is used to heat the flange 11b, and the temperature on the exhaust side of the susceptor 30 becomes lower than in the conventional case. It is considered that what is being done is affecting.
　なお、確認試験の例では、載置台２０のオフセット量は７０ｍｍであるとしたが、図４からも明らかな通り、上記オフセット量が６０～１２０ｍｍの範囲であれば、同様の結果を得ることができる。 In addition, in the example of the confirmation test, the offset amount of the mounting table 20 is 70 mm, but as is clear from FIG. 4, similar results can be obtained if the offset amount is in the range of 60 to 120 mm. it can.
（第２実施形態）
　図９は、第２実施形態に係る成膜装置の構成の概略を説明するための図であり、当該成膜装置が有する処理容器１１の周囲の状態を示した模式断面図である。
　第１の実施形態では、誘導コイル１４の密度がガス流方向に関して均一であった。そのため、誘導コイル１４を用いた誘導加熱による、ガス流方向における単位長さ当たりの加熱量が一定であった。それに対し、本実施形態では、図９に示すように、誘導コイル１４の密度が、回転軸２１に対して排気側より給気側の方が大きい。したがって、誘導コイル１４を用いた誘導加熱による、ガス流方向における単位長さ当たりの加熱量が、回転軸２１に対して排気側より給気側の方が大きくなっている。これにより、載置台空間Ｓ１における給気側の処理ガスの温度を上げながら排気側の処理ガスの温度を従来の成膜装置より下げることが容易となる。つまり、ＳｉＣ膜の品質を容易に向上させることができる。 (Second embodiment)
FIG. 9 is a diagram for explaining the outline of the configuration of the film forming apparatus according to the second embodiment, and is a schematic cross-sectional view showing a state around the processing container 11 included in the film forming apparatus.
In the first embodiment, the density of the induction coil 14 is uniform in the gas flow direction. Therefore, the amount of heating per unit length in the gas flow direction by the induction heating using the induction coil 14 was constant. On the other hand, in the present embodiment, as shown in FIG. 9, the density of the induction coil 14 is larger on the air supply side than on the exhaust side with respect to the rotating shaft 21. Therefore, the heating amount per unit length in the gas flow direction by the induction heating using the induction coil 14 is larger on the air supply side than on the exhaust side with respect to the rotating shaft 21. As a result, it becomes easier to lower the temperature of the process gas on the exhaust side than the conventional film forming apparatus while increasing the temperature of the process gas on the supply side in the mounting table space S1. That is, the quality of the SiC film can be easily improved.
　誘導コイル１４を用いた誘導加熱による、ガス流方向における単位長さ当たりの加熱量を、回転軸２１に対して排気側より給気側で大きくさせる方法は、以下の方法であってもよい。すなわち、誘導コイル１４に印加する高周波電力を、回転軸２１に対して排気側より給気側の方で大きくする方法である。この方法を採用する場合、高周波電源１４ａは排気側と給気側とで別々に設けてもよい。 The method of increasing the heating amount per unit length in the gas flow direction by the induction heating using the induction coil 14 from the exhaust side to the supply side with respect to the rotating shaft 21 may be the following method. That is, this is a method in which the high-frequency power applied to the induction coil 14 is made larger on the air supply side than on the exhaust side with respect to the rotating shaft 21. When this method is adopted, the high frequency power supply 14a may be separately provided on the exhaust side and the air supply side.
（第３実施形態）
　図１０は、第３実施形態に係る成膜装置の構成の概略を説明するための図であり、当該成膜装置が有する処理容器１１の周囲の状態を示した模式断面図である。
　従来の成膜装置における給気側で不純物濃度が高い理由として、前述のようにＣ／Ｓｉ比が低いことがある。本実施形態では、図１０に示すように、ガス導入部としての給気側の管路３２ｂ１を多段に形成し、上段からＳｉＨ４ガスを供給し、下段から他の処理ガス（例えば、Ｈ２ガスとＣ３Ｈ８ガス）を供給する。これにより、Ｓｉの基板Ｗへの拡散を遅らせて、給気側の基板表面付近におけるＣ／Ｓｉ比を上げることができる。したがって、給気側の不純物濃度をさらに下げることができる。よって、不純物濃度の均一性をさらに向上させることができる。 (Third Embodiment)
FIG. 10 is a diagram for explaining the outline of the configuration of the film forming apparatus according to the third embodiment, and is a schematic cross-sectional view showing a state around the processing container 11 included in the film forming apparatus.
The reason why the impurity concentration is high on the air supply side in the conventional film forming apparatus is that the C/Si ratio is low as described above. In the present embodiment, as shown in FIG. 10, the air supply side conduit 32b 1 as a gas introduction portion is formed in multiple stages, SiH 4 gas is supplied from the upper stage, and another process gas (for example, H 2 2 gas and C 3 H 8 gas) are supplied. As a result, the diffusion of Si into the substrate W can be delayed, and the C/Si ratio in the vicinity of the substrate surface on the air supply side can be increased. Therefore, the impurity concentration on the air supply side can be further reduced. Therefore, the uniformity of the impurity concentration can be further improved.
　なお、本発明者らが調査したところによれば、成膜速度は、給気側で最も高く排気側にかけて減少していく。この現象は、給気側で成長を律速するＳｉの消費が多く、排気側に向けてＳｉ密度が減少していることに対応する。したがって、本実施形態のように、給気側の管路３２ｂ１を多段に形成し、上段からＳｉＨ４ガスを供給し、下段から他の処理ガスを供給することにより、給気側において、Ｓｉの基板Ｗへの拡散を遅らせ、成長を抑制することができる。 According to a study conducted by the present inventors, the film forming rate is highest on the air supply side and decreases on the air exhaust side. This phenomenon corresponds to a large consumption of Si that controls the growth on the air supply side and a decrease in the Si density toward the exhaust side. Therefore, as in the present embodiment, the gas supply side conduit 32b 1 is formed in multiple stages, the SiH 4 gas is supplied from the upper stage, and the other process gas is supplied from the lower stage, so that Si on the supply side is reduced. Diffusion to the substrate W can be delayed and growth can be suppressed.
　給気側で成長速度が速いことは、予熱空間Ｓ２での成長に多くのＳｉが消費されることを意味するところ、本実施形態によれば、給気側で成長速度を遅くすることができるため、予熱空間Ｓ２での成長に多くのＳｉが消費されるのを防ぐことができる。
　また、載置台２０のオフセットにより、給気側における不純物の高濃度部の発生は解消することができるものの、載置台２０のオフセットを行っても、給気側では不純物濃度の変動が大きく、排気側では不純物濃度の変動が緩やかである。
　本実施形態では、給気側で成長速度を遅くすることで、上述の不純物濃度の変動が緩やかな領域で成長する部分の割合が増えるため、膜形成時に載置台２０を回転させた際の不純物濃度の均一性をさらに改善することができる。 The fact that the growth rate is fast on the air supply side means that a large amount of Si is consumed for the growth in the preheating space S2. However, according to the present embodiment, the growth rate can be slowed on the air supply side. Therefore, it is possible to prevent a large amount of Si from being consumed for growth in the preheating space S2.
Although the placement table 20 is offset, it is possible to eliminate the occurrence of a high-concentration portion of impurities on the air supply side. However, even if the placement table 20 is offset, the fluctuation of the impurity concentration on the air supply side is large, and the exhaust gas is exhausted. On the side, the fluctuation of the impurity concentration is gentle.
In the present embodiment, by slowing the growth rate on the air supply side, the proportion of the portion that grows in the region where the above-mentioned fluctuation of the impurity concentration is gentle increases. Therefore, impurities when the mounting table 20 is rotated during film formation are increased. The uniformity of concentration can be further improved.
　本実施形態では、図示するように、管路３２ｂ１は、上段の方が下段より太くなっている。これは、管路３２ｂ１の上段を介して基板Ｗが搬出入されるからである。このように、上段と下段で太さが異なる場合、上段からの処理ガスの流速と下段からの処理ガスの流速が等しくなるように、細い下段からの処理ガスの流量を少なくしてもよい。
　なお、図の例では、管路３２ｂ１の上段と下段を隔てる仕切り４０が設けられている。しかし、当該管路３２ｂ１への処理ガスの射出速度が高い場合、処理ガスの直進性が良いため、当該管路３２ｂ１へのガス供給が上段と下段で分かれていれば、仕切り４０を設けなくてもよい。 In the present embodiment, as shown in the figure, the upper portion of the conduit 32b 1 is thicker than the lower portion. This is because the substrate W is loaded and unloaded through the upper stage of the conduit 32b 1 . As described above, when the upper and lower stages have different thicknesses, the flow rate of the process gas from the thin lower stage may be reduced so that the flow rate of the process gas from the upper stage becomes equal to the flow rate of the process gas from the lower stage.
In the example shown, the partition 40 is provided which separates the upper and lower conduits 32 b 1. However, when the injection speed of the processing gas into the pipeline 32b 1 is high, the straightness of the processing gas is good. Therefore, if the gas supply to the pipeline 32b 1 is divided into the upper stage and the lower stage, the partition 40 is provided. You don't have to.
　以上の例では、Ｓｉ含有ガスとハロゲン含有ガスとの両方を供給していたが、シリコン及びハロゲン元素の両方を含むガス、例えば、ＳｉＣｌ４ガス、トリクロロシラン（ＳｉＨＣｌ３）ガスや、ＳｉＨ２Ｃｌ２ガス、モノクロロシラン（ＳｉＨ３Ｃｌ）ガス、テトラフルオロシラン（ＳｉＦ４）ガス、トリフルオロシラン（ＳｉＨＦ３）ガス、ジフルオロシランガス（ＳｉＨ２Ｆ２）ガス、モノフルオロシラン（ＳｉＨ３Ｆ）ガスを供給するようにしてもよい。
　なお、シリコン及びハロゲン元素の両方を含むガスと共に、ハロゲン含有ガスを供給してもよい。 In the above example, both the Si-containing gas and the halogen-containing gas were supplied, but a gas containing both silicon and a halogen element, for example, SiCl 4 gas, trichlorosilane (SiHCl 3 ) gas, or SiH 2 Cl. 2 gas, monochlorosilane (SiH 3 Cl) gas, tetrafluorosilane (SiF 4 ) gas, trifluorosilane (SiHF 3 ) gas, difluorosilane gas (SiH 2 F 2 ) gas, monofluorosilane (SiH 3 F) gas It may be supplied.
Note that the halogen-containing gas may be supplied together with the gas containing both silicon and the halogen element.
　以上の説明は、ｎ型ＳｉＣ膜の成膜に関するものであるが、ｐ型のＳｉＣ膜の成長にも各実施形態は適用することができる。ただし、不純物濃度の分布の傾向等は、ｎ型ＳｉＣ膜と、ｐ型ＳｉＣ膜とでは反対になる。
　また、ｐ型ＳｉＣ膜の場合は、ｎ型ＳｉＣ膜に比べて、不純物濃度が基板温度に依存する。それに対し、各実施形態では、載置台空間Ｓ１の給気側の処理ガスの温度を予熱することで、基板Ｗが処理ガスにより冷えにくくなるため、基板温度の均一性が向上する。 Although the above description relates to the formation of the n-type SiC film, each embodiment can be applied to the growth of the p-type SiC film. However, the tendency of the distribution of the impurity concentration is opposite between the n-type SiC film and the p-type SiC film.
Further, in the case of the p-type SiC film, the impurity concentration depends on the substrate temperature as compared with the n-type SiC film. On the other hand, in each of the embodiments, by preheating the temperature of the processing gas on the air supply side of the mounting table space S1, it becomes difficult for the substrate W to be cooled by the processing gas, and thus the uniformity of the substrate temperature is improved.
　今回開示された実施形態はすべての点で例示であって制限的なものではないと考えられるべきである。上記の実施形態は、添付の請求の範囲及びその主旨を逸脱することなく、様々な形態で省略、置換、変更されてもよい。 The embodiments disclosed this time are to be considered as illustrative in all points and not restrictive. The above-described embodiments may be omitted, replaced, or modified in various forms without departing from the scope and spirit of the appended claims.
　なお、以下のような構成も本開示の技術的範囲に属する。
（１）処理対象基板にＳｉＣ膜を形成する成膜装置であって、
誘導加熱により加熱されるサセプタと、
前記サセプタ内に配置され、処理対象基板が載置された状態で回転軸を中心に回転する載置台と、
前記載置台に載置された処理対象基板の表面に沿って処理ガスが流れるように、前記サセプタの内部空間に対し側方から前記処理ガスを供給するガス供給機構と、を有し、
前記サセプタの内部空間は、前記処理ガスの流れ方向における前記載置台より上流側に、前記載置台に載置された処理対象基板に供給される前記処理ガスを予熱する予熱空間を有する、成膜装置。
　前記（１）によれば、載置台が位置する空間内の、処理ガスの流れ方向における下流側（排気側）の処理ガスの温度上昇を抑えながら、処理ガスの流れ方向における上流側（給気側）の処理ガスの温度を従来の成膜装置より上げることができる。また、載置台が位置する空間における排気側の処理ガスの温度を下げながら、給気側の処理ガスの温度を上げることができる。したがって、サイドフロー方式で原料ガスが供給されて形成されるＳｉＣ膜内の不純物濃度分布を均一にすることができる。また、処理ガスとしてハロゲン含有ガスも供給する場合において、上記ＳｉＣ膜内の欠陥を少なくすることができる。つまり、サイドフロー方式で原料ガスが供給される成膜装置によって形成されるＳｉＣ膜の品質を向上させることができる。 The following configurations also belong to the technical scope of the present disclosure.
(1) A film forming apparatus for forming a SiC film on a substrate to be processed,
A susceptor heated by induction heating,
A mounting table which is disposed in the susceptor and rotates about a rotation axis in a state where a substrate to be processed is mounted,
The processing gas flows along the surface of the processing target substrate placed on the mounting table, and has a gas supply mechanism that supplies the processing gas from the side to the internal space of the susceptor,
The internal space of the susceptor has a preheating space for preheating the processing gas supplied to the processing target substrate mounted on the mounting table, on the upstream side of the mounting table in the flow direction of the processing gas. apparatus.
According to the above (1), while suppressing a temperature rise of the processing gas on the downstream side (exhaust side) in the flow direction of the processing gas in the space where the mounting table is located, the upstream side (supply air) in the flow direction of the processing gas is controlled. The temperature of the processing gas (side) can be raised more than that of the conventional film forming apparatus. Further, it is possible to raise the temperature of the process gas on the air supply side while lowering the temperature of the process gas on the exhaust side in the space where the mounting table is located. Therefore, it is possible to make the impurity concentration distribution uniform in the SiC film formed by supplying the source gas by the side flow method. Further, when a halogen-containing gas is also supplied as the processing gas, it is possible to reduce defects in the SiC film. That is, it is possible to improve the quality of the SiC film formed by the film forming apparatus to which the source gas is supplied by the side flow method.
（２）前記載置台に対する回転軸が、前記処理ガスの流れ方向における、前記サセプタの中心軸より下流側に位置することにより、前記予熱空間が形成されている、前記（１）に記載の成膜装置。 (2) The preheating space is formed by the rotation axis with respect to the mounting table being located downstream of the central axis of the susceptor in the flow direction of the processing gas, so that the preheating space is formed. Membrane device.
（３）誘導加熱による、前記処理ガスの流れ方向における単位長さ当たりの加熱量は、前記処理ガスの流れ方向における前記回転軸より上流側の部分が、前記処理ガスの流れ方向における前記回転軸より下流側の部分に比べて大きい、前記（１）または（２）に記載の成膜装置。
　前記（３）によれば、ＳｉＣ膜の品質を容易に向上させることができる。 (3) The amount of heating per unit length in the flow direction of the processing gas by induction heating is such that the portion upstream of the rotation shaft in the flow direction of the processing gas is the rotation shaft in the flow direction of the processing gas. The film forming apparatus according to (1) or (2), which is larger than a portion on a more downstream side.
According to the above (3), the quality of the SiC film can be easily improved.
（４）前記ガス供給機構からの処理ガスを、前記サセプタの内部空間に導入するガス導入部を有し、
前記ガス導入部は、上下方向に多段に形成され、前記処理ガスとしてのシリコン含有ガスを上段から導入する、前記（１）～（３）のいずれか１に記載の成膜装置。
　前記（４）によれば、ＳｉＣ膜内の不純物濃度の均一性をさらに向上させることができる。 (4) It has a gas introduction part for introducing the processing gas from the gas supply mechanism into the internal space of the susceptor,
The film introduction apparatus according to any one of (1) to (3) above, wherein the gas introduction unit is formed in multiple stages in the vertical direction and introduces the silicon-containing gas as the processing gas from the upper stage.
According to the above (4), it is possible to further improve the uniformity of the impurity concentration in the SiC film.
（５）前記ガス導入部は、前記処理ガスとしての炭素含有ガスを下段から導入する、前記（４）に記載の成膜装置。 (5) The film forming apparatus according to (4), wherein the gas introduction unit introduces a carbon-containing gas as the processing gas from the lower stage.
（６）前記ガス供給機構は、前記処理ガスとして、シリコン含有ガス及びハロゲン元素含有ガスを供給する、前記（１）～（５）のいずれか１に記載の成膜装置。 (6) The film forming apparatus according to any one of (1) to (5), wherein the gas supply mechanism supplies a silicon-containing gas and a halogen-element-containing gas as the processing gas.
（７）前記ガス供給機構は、前記処理ガスとして、シリコン及びハロゲン元素を含有するガスを導入する、前記（１）～（５）のいずれか１に記載の成膜装置。 (7) The film forming apparatus according to any one of (1) to (5), wherein the gas supply mechanism introduces a gas containing silicon and a halogen element as the processing gas.
（８）成膜装置により処理対象基板にＳｉＣ膜を形成する成膜方法であって、
前記成膜装置は、
誘導加熱により加熱されるサセプタと、
前記サセプタ内に配置され、処理対象基板が載置された状態で回転軸を中心に回転する載置台と、を有し、
当該成膜方法は、
前記載置台に載置された処理対象基板の表面に沿って処理ガスが流れるように、前記サセプタの内部空間に対し側方から前記処理ガスを導入する工程と、
前記処理ガスの流れ方向における前記載置台より上流側に位置する予熱空間で、前記載置台に載置された処理対象基板に供給される前記処理ガスを予熱する工程と、を有する、成膜方法。 (8) A film forming method for forming a SiC film on a substrate to be processed by a film forming apparatus,
The film forming apparatus,
A susceptor heated by induction heating,
A mounting table that is disposed in the susceptor and that rotates about a rotation axis in a state in which a substrate to be processed is mounted,
The film forming method is
A step of introducing the processing gas from the side to the internal space of the susceptor so that the processing gas flows along the surface of the processing target substrate placed on the mounting table,
A preheating space located upstream of the mounting table in the flow direction of the processing gas, and preheating the processing gas supplied to the processing target substrate mounted on the mounting table. ..
１　　成膜装置
２０　載置台
２１　回転軸
３０　サセプタ
Ｓ　　内部空間
Ｓ１　載置台空間
Ｓ２　予熱空間
Ｗ　　基板 1 film forming apparatus 20 mounting table 21 rotating shaft 30 susceptor S internal space S1 mounting table space S2 preheating space W substrate

Claims (8)

  1. 処理対象基板にＳｉＣ膜を形成する成膜装置であって、
    誘導加熱により加熱されるサセプタと、
    前記サセプタ内に配置され、処理対象基板が載置された状態で回転軸を中心に回転する載置台と、
    前記載置台に載置された処理対象基板の表面に沿って処理ガスが流れるように、前記サセプタの内部空間に対し側方から前記処理ガスを供給するガス供給機構と、を有し、
    前記サセプタの内部空間は、前記処理ガスの流れ方向における前記載置台より上流側に、前記載置台に載置された処理対象基板に供給される前記処理ガスを予熱する予熱空間を有する、成膜装置。     A film forming apparatus for forming a SiC film on a substrate to be processed,
    A susceptor heated by induction heating,
    A mounting table which is disposed in the susceptor and rotates about a rotation axis in a state where a substrate to be processed is mounted,
    The processing gas flows along the surface of the processing target substrate placed on the mounting table, and has a gas supply mechanism that supplies the processing gas from the side to the internal space of the susceptor,
    The internal space of the susceptor has a preheating space for preheating the processing gas supplied to the processing target substrate mounted on the mounting table, on the upstream side of the mounting table in the flow direction of the processing gas. apparatus.
  2. 前記載置台に対する回転軸が、前記処理ガスの流れ方向における、前記サセプタの中心軸より下流側に位置することにより、前記予熱空間が形成されている、請求項１に記載の成膜装置。 The film forming apparatus according to claim 1, wherein the preheating space is formed by arranging a rotation axis with respect to the mounting table on a downstream side of a central axis of the susceptor in a flow direction of the processing gas.
  3. 誘導加熱による、前記処理ガスの流れ方向における単位長さ当たりの加熱量は、前記処理ガスの流れ方向における前記回転軸より上流側の部分が、前記処理ガスの流れ方向における前記回転軸より下流側の部分に比べて大きい、請求項１または２に記載の成膜装置。 The amount of heating per unit length in the flow direction of the processing gas by induction heating is such that the portion upstream of the rotation axis in the flow direction of the processing gas is downstream of the rotation axis in the flow direction of the processing gas. The film forming apparatus according to claim 1 or 2, which is larger than the portion.
  4. 前記ガス供給機構からの処理ガスを、前記サセプタの内部空間に導入するガス導入部を有し、
    前記ガス導入部は、上下方向に多段に形成され、前記処理ガスとしてのシリコン含有ガスを上段から導入する、請求項１～３のいずれか１項に記載の成膜装置。     The processing gas from the gas supply mechanism, having a gas introduction portion for introducing into the internal space of the susceptor,
    The film forming apparatus according to any one of claims 1 to 3, wherein the gas introduction unit is formed in multiple stages in the vertical direction and introduces the silicon-containing gas as the processing gas from the upper stage.
  5. 前記ガス導入部は、前記処理ガスとしての炭素含有ガスを下段から導入する、請求項４に記載の成膜装置。 The film forming apparatus according to claim 4, wherein the gas introducing unit introduces a carbon-containing gas as the processing gas from a lower stage.
  6. 前記ガス供給機構は、前記処理ガスとして、シリコン含有ガス及びハロゲン元素含有ガスを供給する、請求項１～５のいずれか１項に記載の成膜装置。 The film forming apparatus according to claim 1, wherein the gas supply mechanism supplies a silicon-containing gas and a halogen-element-containing gas as the processing gas.
  7. 前記ガス供給機構は、前記処理ガスとして、シリコン及びハロゲン元素を含有するガスを導入する、請求項１～５のいずれか項に記載の成膜装置。 The film forming apparatus according to claim 1, wherein the gas supply mechanism introduces a gas containing silicon and a halogen element as the processing gas.
  8. 成膜装置により処理対象基板にＳｉＣ膜を形成する成膜方法であって、
    前記成膜装置は、
    誘導加熱により加熱されるサセプタと、
    前記サセプタ内に配置され、処理対象基板が載置された状態で回転軸を中心に回転する載置台と、を有し、
    当該成膜方法は、
    前記載置台に載置された処理対象基板の表面に沿って処理ガスが流れるように、前記サセプタの内部空間に対し側方から前記処理ガスを導入する工程と、
    前記処理ガスの流れ方向における前記載置台より上流側に位置する予熱空間で、前記載置台に載置された処理対象基板に供給される前記処理ガスを予熱する工程と、を有する、成膜方法。
          A film forming method for forming a SiC film on a substrate to be processed by a film forming apparatus, comprising:
    The film forming apparatus,
    A susceptor heated by induction heating,
    A mounting table that is disposed in the susceptor and that rotates about a rotation axis in a state in which a substrate to be processed is mounted,
    The film forming method is
    A step of introducing the processing gas from the side to the internal space of the susceptor so that the processing gas flows along the surface of the processing target substrate placed on the mounting table,
    A preheating space located upstream of the mounting table in the flow direction of the processing gas, and preheating the processing gas supplied to the processing target substrate mounted on the mounting table. ..
PCT/JP2020/002738 2019-02-01 2020-01-27 Film forming apparatus and film forming method WO2020158657A1 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
JP2019017114A JP2020126885A (en) 2019-02-01 2019-02-01 Film forming apparatus and film forming method
JP2019-017114 2019-07-31

Publications (1)

Publication Number Publication Date
WO2020158657A1 true WO2020158657A1 (en) 2020-08-06

Family

ID=71841060

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/JP2020/002738 WO2020158657A1 (en) 2019-02-01 2020-01-27 Film forming apparatus and film forming method

Country Status (2)

Country Link
JP (1) JP2020126885A (en)
WO (1) WO2020158657A1 (en)

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2010267702A (en) * 2009-05-13 2010-11-25 Sumitomo Electric Ind Ltd Device and method for forming chemical vapor deposition semiconductor film
JP2012069635A (en) * 2010-09-22 2012-04-05 Hitachi Kokusai Electric Inc Deposition device, wafer holder and deposition method
WO2017043165A1 (en) * 2015-09-11 2017-03-16 住友電気工業株式会社 Silicon carbide epitaxial substrate, and method for manufacturing silicon carbide semiconductor device
WO2017056691A1 (en) * 2015-09-29 2017-04-06 住友電気工業株式会社 Method of manufacturing silicon carbide epitaxial substrate, method of manufacturing silicon carbide semiconductor device, and silicon carbide epitaxial substrate manufacturing device

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2010267702A (en) * 2009-05-13 2010-11-25 Sumitomo Electric Ind Ltd Device and method for forming chemical vapor deposition semiconductor film
JP2012069635A (en) * 2010-09-22 2012-04-05 Hitachi Kokusai Electric Inc Deposition device, wafer holder and deposition method
WO2017043165A1 (en) * 2015-09-11 2017-03-16 住友電気工業株式会社 Silicon carbide epitaxial substrate, and method for manufacturing silicon carbide semiconductor device
WO2017056691A1 (en) * 2015-09-29 2017-04-06 住友電気工業株式会社 Method of manufacturing silicon carbide epitaxial substrate, method of manufacturing silicon carbide semiconductor device, and silicon carbide epitaxial substrate manufacturing device

Also Published As

Publication number Publication date
JP2020126885A (en) 2020-08-20

Similar Documents

Publication Publication Date Title
US9177799B2 (en) Semiconductor device manufacturing method and substrate manufacturing method of forming silicon carbide films on the substrate
US10494737B2 (en) Apparatus for producing SiC epitaxial wafer and method for producing SiC epitaxial wafer
JP5562409B2 (en) Semiconductor device manufacturing method, substrate manufacturing method, and substrate processing apparatus
JP5529634B2 (en) Substrate processing apparatus, semiconductor device manufacturing method, and substrate manufacturing method
JP5393895B2 (en) Semiconductor device manufacturing method and substrate processing apparatus
JP3725598B2 (en) Epitaxial wafer manufacturing method
WO2012115170A1 (en) Substrate processing device, method for producing substrate, and method for producing semiconductor device
US20100282166A1 (en) Heat treatment apparatus and method of heat treatment
JP2011205059A (en) Method of manufacturing semiconductor device, method of manufacturing substrate and substrate processing apparatus
JP5910430B2 (en) Method for manufacturing epitaxial silicon carbide wafer
WO2019044392A1 (en) Vapor-phase deposition method
US11692266B2 (en) SiC chemical vapor deposition apparatus
JP2015018869A (en) Substrate processing apparatus
WO2020158657A1 (en) Film forming apparatus and film forming method
JP2011077476A (en) Susceptor for epitaxial growth
JP2021031336A (en) SiC CHEMICAL VAPOR DEPOSITION APPARATUS
JP7448076B2 (en) SiC epitaxial wafer
US20210108331A1 (en) Film forming apparatus and film forming method
KR101238841B1 (en) Susceptor for chemical vapor deposition apparatus and chemical vapor deposition apparatus having the same
KR20120090676A (en) Susceptor for chemical vapor deposition apparatus and chemical vapor deposition apparatus having the same
JP7367497B2 (en) Method for forming a silicon carbide polycrystalline film and manufacturing method for a silicon carbide polycrystalline substrate
JP2022067843A (en) Silicon carbide single crystal substrate, and production method thereof
JP2014123616A (en) Substrate processing apparatus
KR20120036514A (en) Susceptor for chemical vapor deposition apparatus and chemical vapor deposition apparatus having the same
KR101224567B1 (en) Susceptor for chemical vapor deposition apparatus and method for manufacturing epitaxial wafer

Legal Events

Date Code Title Description
121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 20749651

Country of ref document: EP

Kind code of ref document: A1

NENP Non-entry into the national phase

Ref country code: DE

122 Ep: pct application non-entry in european phase

Ref document number: 20749651

Country of ref document: EP

Kind code of ref document: A1