JP2014159347A - Manufacturing apparatus and method of silicon carbide single crystal substrate - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a manufacturing apparatus and method of a silicon carbide single crystal substrate that can reduce a variation of crystal quality in the surface of a silicon carbide single crystal substrate and reduce a stress generated in a silicon carbide single crystal during growth of the silicon carbide single crystal.SOLUTION: A manufacturing apparatus 11 of a silicon carbide single crystal substrate 100a includes a raw material housing part 8 and a seed substrate holding part 1. The seed substrate holding part 1 is disposed at a position opposed to the raw material housing part 8. The seed substrate holding part 1 comprises a plate part 2 having a first principal surface 2a and a second principal surface 2b which are opposed to each other, a body part 4 in contact with the first principal surface 2a of the plate part 2, and a connection part 3 for fixing the plate part 2 to the body part 4. The thickness T1 of the plate part 2 is less than the thickness T2 of the body part 4.

Description

  The present invention relates to an apparatus and a method for manufacturing a silicon carbide single crystal substrate.

  In recent years, silicon carbide single crystal substrates have begun to be used for manufacturing semiconductor devices. Silicon carbide has a larger band gap than silicon. Therefore, a semiconductor device using a silicon carbide single crystal substrate has advantages such as high breakdown voltage, low on-resistance, and small deterioration in characteristics under a high temperature environment.

  For example, in Japanese Patent Application Laid-Open No. 2002-201097 (Patent Document 1), a silicon carbide single crystal is grown on a seed substrate by sublimating a silicon carbide raw material in a crucible, and then the silicon carbide single crystal is sliced. A method of manufacturing a silicon carbide single crystal substrate is described. Japanese Patent Application Laid-Open No. 2011-251884 (Patent Document 2) describes that the seed substrate mounting portion for holding the seed substrate (seed crystal) is formed of a thin plate separate from the crucible lid. . It is described that since the seed substrate mounting portion is formed of a thin plate, the amount of thermal deformation is reduced when heated, so that the thermal stress transmitted from the seed substrate mounting portion to the seed substrate is also reduced.

JP 2002-201097 A JP 2011-251884 A

  However, according to the silicon carbide single crystal manufacturing apparatus described in Japanese Patent Application Laid-Open No. 2011-251884 (Patent Document 2), the mounting plate for holding the seed substrate is crucible by a leg portion provided near the center of the mounting plate. The surface of the mounting plate is spaced apart from the surface of the lid portion of the crucible. Therefore, since the seed substrate arranged near the center of the mounting plate is in contact with the lid portion via the leg portion, heat conduction is efficiently performed, but the outer portion of the mounting plate is connected to the surface of the lid portion. They are spaced apart and do not conduct heat efficiently. As a result, the temperature distribution on the surface of the seed substrate is increased, and the in-plane distribution of the crystal quality of the silicon carbide single crystal grown on the surface of the seed substrate is increased.

  The present invention has been made to solve the above-described problems. The object of the present invention is to reduce the in-plane distribution of the crystal quality of the silicon carbide single crystal substrate and to perform carbonization during the growth of the silicon carbide single crystal. An object of the present invention is to provide a silicon carbide single crystal substrate manufacturing apparatus and manufacturing method capable of reducing stress generated in a silicon single crystal.

  An apparatus for manufacturing a silicon carbide single crystal substrate according to the present invention includes a raw material container and a seed substrate holder. The seed substrate holding part is arranged at a position facing the raw material container. The seed substrate holding portion includes a plate portion having a first main surface and a second main surface facing each other, a main body portion in contact with the first main surface of the plate portion, and a connection portion for fixing the plate portion to the main body portion. Including. The thickness of the plate portion is smaller than the thickness of the main body portion.

  According to the silicon carbide single crystal substrate manufacturing apparatus of the present invention, the thickness of the plate portion on which the seed substrate is held is smaller than the thickness of the main body portion. Stress generated in the seed substrate and the silicon carbide single crystal grown on the seed substrate due to the difference in thermal expansion between the material constituting the seed substrate and the material constituting the plate part during the growth of the silicon carbide single crystal Since the plate portion is deformed according to the deformation of the seed substrate, it can be efficiently reduced. Further, since the main body is in contact with the first main surface of the plate portion, the in-plane temperature distribution of the seed substrate fixed on the second main surface of the plate portion is reduced. As a result, it is possible to reduce the in-plane distribution of the crystal quality of the silicon carbide single crystal substrate which is obtained by slicing a silicon carbide single crystal grown on the seed substrate along a plane perpendicular to the growth direction of the silicon carbide single crystal. .

  Preferably, in the silicon carbide single crystal substrate manufacturing apparatus according to the above, the main body includes a buffer material that is in contact with the first main surface of the plate and includes carbon. Thereby, when a board part deform | transforms, a buffer material can deform | transform according to a deformation | transformation of a board part. As a result, the stress generated in the seed substrate and silicon carbide single crystal fixed to the plate portion can be efficiently reduced.

  Preferably, in the silicon carbide single crystal substrate manufacturing apparatus according to the above, the connection portion includes an adhesive. Thereby, a board part can be efficiently fixed to a main-body part.

  Preferably, in the silicon carbide single crystal substrate manufacturing apparatus according to the above, the connection portion includes a screw. Thereby, a board part can be efficiently fixed to a main-body part.

  Preferably, in the silicon carbide single crystal substrate manufacturing apparatus according to the above, the thermal expansion coefficient at 1000 ° C. of the material constituting the plate portion is 0.8 to 1.2 times the thermal expansion coefficient of silicon carbide at 1000 ° C. It is. Thereby, the stress which generate | occur | produces in a seed substrate and a silicon carbide single crystal can be reduced efficiently.

  The method for manufacturing a silicon carbide single crystal substrate according to the present invention includes the following steps. Seed substrate holding comprising a plate portion having a first main surface and a second main surface facing each other, a main body portion in contact with the first main surface of the plate portion, and a connection portion for fixing the plate portion to the main body portion Department is prepared. The seed substrate is fixed to the second main surface of the plate portion. A silicon carbide single crystal is grown on the surface of the seed substrate. The thickness of the plate portion is smaller than the thickness of the main body portion.

  According to the method for manufacturing a silicon carbide single crystal substrate according to the present invention, the thickness of the plate portion on which the seed substrate is held is smaller than the thickness of the main body portion. Stress generated in the seed substrate and the silicon carbide single crystal grown on the seed substrate due to the difference in thermal expansion between the material constituting the seed substrate and the material constituting the plate part during the growth of the silicon carbide single crystal Since the plate portion is deformed according to the deformation of the seed substrate, it can be efficiently reduced. Further, since the main body is in contact with the first main surface of the plate portion, the in-plane temperature distribution of the seed substrate fixed on the second main surface of the plate portion is reduced. As a result, it is possible to reduce the in-plane distribution of the crystal quality of the silicon carbide single crystal substrate which is obtained by slicing a silicon carbide single crystal grown on the seed substrate along a plane perpendicular to the growth direction of the silicon carbide single crystal. .

  In the method for manufacturing a silicon carbide single crystal substrate according to the above, preferably, the thickness t (mm) of the plate portion is 0 when the thickness of the plate portion is t (mm) and the diameter of the seed substrate is d (mm). 0059 × d (mm) or more and 0.059 × d (mm) or less. If the thickness t (mm) of the plate portion is 0.0059 × d (mm) or more, the rigidity of the plate portion for holding the seed substrate can be sufficiently increased. If the thickness t (mm) of the plate portion is 0.059 × d (mm) or less, the plate portion can be easily deformed according to the deformation of the seed substrate, and the stress of the seed substrate and the silicon carbide single crystal can be reduced. It can be sufficiently reduced.

  Preferably, in the method for manufacturing a silicon carbide single crystal substrate according to the above, the main body portion includes a buffer material in contact with the first main surface of the plate portion and containing carbon. Thereby, when a board part deform | transforms, a buffer material can deform | transform according to a deformation | transformation of a board part. As a result, the stress generated in the seed substrate fixed to the plate part can be efficiently reduced.

  Preferably, in the method for manufacturing a silicon carbide single crystal substrate according to the above, the connection portion includes an adhesive. Thereby, a board part can be efficiently fixed to a main-body part.

  Preferably, in the method for manufacturing a silicon carbide single crystal substrate according to the above, the connection portion includes a screw. Thereby, a board part can be efficiently fixed to a main-body part.

  Preferably, in the method for manufacturing a silicon carbide single crystal substrate according to the above, the thermal expansion coefficient at 1000 ° C. of the material constituting the plate portion is 0.8 to 1.2 times the thermal expansion coefficient of silicon carbide at 1000 ° C. It is. Thereby, the stress which generate | occur | produces in a seed substrate and a silicon carbide single crystal can be reduced efficiently.

  In the method for manufacturing a silicon carbide single crystal substrate according to the above, preferably, the diameter of the silicon carbide single crystal substrate is 100 mm or more. Thereby, a silicon carbide single crystal substrate having a diameter of 100 mm or more can be manufactured.

  According to the present invention, a silicon carbide single crystal substrate manufacturing apparatus capable of reducing the in-plane distribution of crystal quality of a silicon carbide single crystal substrate and reducing the stress generated in the silicon carbide single crystal during the growth of the silicon carbide single crystal. And a manufacturing method can be provided.

It is a cross-sectional schematic diagram for demonstrating schematically the structure of the manufacturing apparatus of the silicon carbide single crystal substrate which concerns on one embodiment of this invention. It is a decomposition section schematic diagram for explaining roughly composition of a seed substrate holding part of a manufacturing device of a silicon carbide single crystal substrate concerning one embodiment of the present invention. It is a cross-sectional schematic diagram for demonstrating schematically the structure of the seed substrate holding | maintenance part of the manufacturing apparatus of the silicon carbide single crystal substrate which concerns on one embodiment of this invention. It is a cross-sectional schematic diagram for demonstrating schematically the structure of the 1st modification of the seed substrate holding | maintenance part of the manufacturing apparatus of the silicon carbide single crystal substrate which concerns on one embodiment of this invention. It is a cross-sectional schematic diagram for demonstrating schematically the structure of the 2nd modification of the seed substrate holding | maintenance part of the manufacturing apparatus of the silicon carbide single crystal substrate which concerns on one embodiment of this invention. It is a cross-sectional schematic diagram for demonstrating schematically the structure of the 3rd modification of the seed substrate holding | maintenance part of the manufacturing apparatus of the silicon carbide single crystal substrate which concerns on one embodiment of this invention. It is a cross-sectional schematic diagram for demonstrating schematically the structure of the 4th modification of the seed substrate holding | maintenance part of the manufacturing apparatus of the silicon carbide single crystal substrate which concerns on one embodiment of this invention. It is a flowchart for demonstrating schematically the manufacturing method of the silicon carbide single crystal substrate which concerns on one embodiment of this invention. 1 is a schematic cross-sectional view for schematically illustrating a first step in a method for manufacturing a silicon carbide single crystal substrate according to one embodiment of the present invention. 1 is a schematic perspective view for schematically illustrating a silicon carbide single crystal substrate manufactured by a method for manufacturing a silicon carbide single crystal substrate according to an embodiment of the present invention.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the following drawings, the same or corresponding parts are denoted by the same reference numerals, and description thereof will not be repeated. In the crystallographic description in this specification, the individual orientation is indicated by [], the collective orientation is indicated by <>, the individual plane is indicated by (), and the collective plane is indicated by {}. As for the negative index, “−” (bar) is attached on the number in crystallography, but in this specification, a negative sign is attached before the number. The angle is described using a system in which the omnidirectional angle is 360 degrees.

  With reference to FIG. 1, the structure of the manufacturing apparatus of the silicon carbide single crystal substrate which concerns on one embodiment of this invention is demonstrated.

  Referring to FIG. 1, silicon carbide single crystal substrate manufacturing apparatus 11 according to the present embodiment mainly includes growth vessel 10 and a heating unit (not shown). The growth vessel 10 is a crucible made of, for example, purified graphite, and mainly includes a seed substrate holding unit 1 and a raw material storage unit 8. The seed substrate holding unit 1 is for holding a seed substrate 5 made of silicon carbide single crystal. Raw material accommodating portion 8 is for accommodating silicon carbide raw material 9 made of, for example, polycrystalline silicon carbide. The seed substrate 5 and the silicon carbide raw material 9 are arranged so as to face each other inside the growth vessel 10.

  In order to heat the growth vessel 10, the silicon carbide raw material 9, the seed substrate 5, and the like, a heating unit (not shown) is disposed outside the growth vessel 10. The heating unit may be, for example, a resistance heating method or an induction heating method. The heating unit may be disposed so as to surround the outer periphery of the raw material container 8 of the growth vessel 10 and may be provided to face the bottom of the raw material container 8 where the silicon carbide raw material 9 is disposed. The heating unit is configured to be able to raise the temperature of silicon carbide raw material 9 to the sublimation temperature of silicon carbide.

  With reference to FIGS. 2-7, the structure of the seed substrate holding | maintenance part of the manufacturing apparatus of the silicon carbide single crystal substrate which concerns on one embodiment of this invention is demonstrated.

  2 and 3, seed substrate holding unit 1 of the silicon carbide single crystal substrate manufacturing apparatus according to the present embodiment mainly includes plate portion 2, main body portion 4, and connecting portion 3. doing. The plate part 2 is a plate-like member having a first main surface 2a and a second main surface 2b facing each other. Second main surface 2b is a surface for holding seed substrate 5 made of silicon carbide single crystal. The thickness T1 of the plate part 2 is smaller than the thickness T2 of the main body part 4. The thickness T1 of the plate part 2 is about 1 mm, for example, and the thickness of the main body part 4 is about 16 mm, for example. Members forming the seed substrate holding portion 1 such as the plate portion 2, the main body portion 4 and the connection portion 3 are made of carbon such as graphite, for example.

  When the diameter of the seed substrate 5 is d1 (mm), the thickness T1 (mm) of the plate portion 2 is more preferably 0.0059 × d1 (mm) or more and 0.059 × d1 (mm) or less. . The seed substrate 5 has a first surface 5a and a second surface 5b facing each other. The first surface 5a of the seed substrate 5 is fixed to the plate portion 2, and the second surface 5b is This is the surface on which the silicon carbide single crystal grows.

  A protruding portion 6 is provided near the center of the first main surface 2 a of the plate portion 2, and the connecting portion 3 is provided via the protruding portion 6. The connection part 3 is a male screw part, for example. On the other hand, a wall surface 4d forming a hole and a female screw portion as a screw portion 4c are provided near the center of the main body portion 4. The connection part 3 is configured to be fixable to the female screw part. The protruding portion 6 of the plate portion 2 may be configured to be in contact with the wall surface 4 d that forms the hole portion of the main body portion 4.

  Referring to FIG. 4, connection portion 3 may be an adhesive, for example. As the adhesive, for example, a material in which carbon powder and a polymer material are mixed with an organic solvent is used. The polymer material is, for example, a phenol resin, and the organic solvent is, for example, a mixed solvent of phenol and ethyl alcohol. The adhesive can bond the plate portion 2 made of carbon and the main body portion 4 made of carbon even near the sublimation temperature of silicon carbide. Specifically, the main body portion 4 is provided with a wall surface 4e that forms a recess having an opening on the surface facing the plate portion 2, and an adhesive as the connecting portion 3 is disposed in contact with the wall surface 4e. Yes.

  The adhesive is in contact with the plate portion 2, and the plate portion 2 and the main body portion 4 are fixed by the adhesive. Of the first main surface 2 a of the plate portion 2, the portion not in contact with the adhesive is in contact with the main body portion 4. The first main surface 2 a of the plate part 2 is in contact with the main body part 4, but is not fixed to the main body part 4. Preferably, most of first main surface 2a of plate portion 2 is in contact with main body portion 4 at a temperature at which silicon carbide sublimes from room temperature. For example, it is preferable that a region of 50% or more of the area of the first main surface 2 a of the plate portion 2 is in contact with the main body portion 4, and a region of 90% or more of the area is in contact with the main body portion 4. Further preferred.

  Referring to FIG. 5, even if a projection 6 near the center of the plate portion 2 of the seed substrate holding portion 1 is provided and the projection 6 is fixed to the main body 4 via an adhesive as the connection portion 3. Good. As shown in FIG. 5, the protruding portion 6 is disposed in a recess formed in the main body portion 4, and the plate portion 2 is fixed to the main body portion 4 via an adhesive so as to cover the surface of the protruding portion 6. May be. A part of the adhesive may be in contact with a part of the first main surface 2 a of the plate part 2. Note that both an adhesive and a screw may be used as the connection portion 3.

  Referring to FIG. 6, main body portion 4 of seed substrate holding portion 1 has rigid body portion 4 a and buffer material 4 b, and buffer material 4 b may be in contact with first main surface 2 a of plate portion 2. The rigid body portion 4a is made of a carbon member such as graphite, and the buffer material 4b is made of a material having higher flexibility and stretchability than the rigid body portion 4a. The buffer material 4b is made of, for example, a graphite sheet. Moreover, it is preferable that the buffer material 4b has a softness | flexibility and a stretching property also in about 2200 degreeC or more and 2400 degrees C or less which are the temperature which can sublimate silicon carbide.

  As shown in FIG. 6, a protrusion 6 is provided near the center of the first main surface 2 a of the plate portion 2, and the plate portion 2 is attached to the rigid portion 4 a by an adhesive disposed on the surface of the protrusion 6. May be fixed. The protruding portion 6 and the plate portion 2 may be integral or separate. The buffer material 4 b is provided so as to be deformable in accordance with the deformation of the plate portion 2. The buffer material 4b is fixed in contact with the rigid body portion 4a. The first main surface 2a of the plate portion 2 is in contact with the buffer material 4b, but is not fixed to the buffer material 4b.

  Referring to FIG. 7, a female screw as connecting portion 3 may be provided on the outer edge side of first main surface 2 a of plate portion 2 of seed substrate holding portion 1. On the outer peripheral portion of the main body portion 4, a male screw portion is provided as a screw portion 4c that is coupled to the female screw. In other words, the female screw as the connection portion 3 is provided so as to surround the main body portion 4. The first main surface 2a of the plate part 2 is in contact with the main body part. The plate portion 2 is fixed to the main body portion 4 with a female screw as the connection portion 3. The first main surface 2 a of the plate portion 2 is in contact with the main body portion 4, but is not fixed to the main body portion 4.

The material which comprises the board part 2 consists of carbon, for example. Preferably, the thermal expansion coefficient at 1000 ° C. of the material constituting plate portion 2 is 0.8 to 1.2 times the thermal expansion coefficient of silicon carbide at 1000 ° C. The thermal expansion coefficient of silicon carbide at 1000 ° C. is about 4 × 10 ⁻⁶ / ° C. or more and 6 × 10 ⁻⁶ / ° C. or less, and the thermal expansion coefficient is considered to be the same as the thermal expansion coefficient of carbon at 1000 ° C.

Next, a method for manufacturing the silicon carbide single crystal substrate according to the present embodiment will be described.
First, referring to FIG. 2 and FIG. 3, a seed substrate holding part preparing step (FIG. 8: S10) is performed. Specifically, seed substrate holding unit 1 for holding seed substrate 5 made of silicon carbide single crystal is prepared. The seed substrate holding portion 1 includes a plate portion 2 having a first main surface 2a and a second main surface 2b facing each other, a main body portion 4 in contact with the first main surface 2a of the plate portion 2, and a plate portion 2 And a connection part 3 for fixing the main body part 4 to the main body part 4. The thickness T1 of the plate part 2 is smaller than the thickness T2 of the main body part 4.

  As shown in FIGS. 3 and 7, the connection portion 3 may be a screw, and as shown in FIGS. 4 to 6, the connection portion 3 may be an adhesive. Moreover, both a screw and an adhesive may be used as the connection part 3. Preferably, the thermal expansion coefficient at 1000 ° C. of the material constituting plate portion 2 is 0.8 to 1.2 times the thermal expansion coefficient of silicon carbide at 1000 ° C.

  Next, a seed substrate holding step (FIG. 8: S20) is performed. Specifically, seed substrate 5 made of, for example, a polytype 4H hexagonal silicon carbide single crystal is prepared. The seed substrate 5 has a first surface 5a and a second surface 5b facing each other. The first surface 5 a of the seed substrate 5 is fixed to the second main surface 2 b of the plate part 2. Second surface 5b of seed substrate 5 is a surface on which a silicon carbide single crystal grows. Seed substrate 5 is fixed to second main surface 2b of plate portion 2 by, for example, a resin adhesive. The resin adhesive may be made of the same material as the adhesive for connecting the plate portion 2 and the main body portion 4. The second surface 5b of the seed substrate 5 may be, for example, a surface that is off by about 8 ° or less from the {0001} plane, or may be a {0-33-8} plane.

  When the diameter of the seed substrate 5 is d1 (mm), the thickness T1 (mm) of the plate portion 2 of the seed substrate holding unit 1 is 0.0059 × d1 (mm) or more and 0.059 × d1 (mm) or less. It is preferable that The diameter d1 of the seed substrate 5 is preferably 100 mm (about 4 inches) or more, more preferably 150 mm (about 6 inches) or more.

  Next, a crystal growth step (FIG. 8: S30) is performed. Specifically, referring to FIG. 9, growth vessel 10 is placed in an inert gas atmosphere such as argon, for example, the temperature of seed substrate 5 is about 2300 ° C., and the temperature of silicon carbide raw material 9 is 2400 ° C. The growth vessel 10 is heated to a degree. Thereafter, the pressure of the inert gas is reduced to, for example, about 0.1 kPa to 5 kPa, whereby silicon carbide raw material 9 starts sublimation, and silicon carbide single crystal 100 is formed on second main surface 2b of seed substrate 5. Growth begins.

  Next, the silicon carbide single crystal 100 grown on the second surface 5 b of the seed substrate 5 is taken out from the growth vessel 10. Thereafter, silicon carbide single crystal substrate 100a (see FIG. 10) is obtained by slicing silicon carbide single crystal 100 with, for example, a wire saw. Silicon carbide single crystal substrate 100a has a diameter d2 that is approximately equal to or slightly larger than seed substrate diameter d1. Silicon carbide single crystal substrate 100a has a diameter d1 of preferably 100 mm (about 4 inches) or more, more preferably 150 mm (about 6 inches) or more.

  Next, the function and effect of the silicon carbide single crystal substrate manufacturing apparatus and method according to the present embodiment will be described.

  According to silicon carbide single crystal substrate 100a manufacturing apparatus 11 according to the present embodiment, thickness T1 of plate portion 2 on which seed substrate 5 is held is smaller than thickness T2 of main body portion 4. Silicon carbide single crystal 100 grown on seed substrate 5 and seed substrate 5 due to the difference in thermal expansion between the material constituting seed substrate 5 and the material constituting plate portion 2 during the growth of silicon carbide single crystal The stress generated in the plate portion 2 is deformed according to the deformation of the seed substrate 5, whereby the stress can be efficiently reduced. Moreover, since the main-body part 4 touches the 1st main surface 2a of the board part 2, the in-plane temperature distribution of the seed substrate 5 fixed on the 2nd main surface 2b of the board part 2 is reduced. As a result, the in-plane distribution of the crystal quality of silicon carbide single crystal substrate 100a obtained by slicing and cutting silicon carbide single crystal 100 grown on seed substrate 5 along a plane perpendicular to the growth direction of silicon carbide single crystal 100 is reduced. can do. Further, cracks in silicon carbide single crystal substrate 100a can be suppressed.

  In addition, according to silicon carbide single crystal substrate 100a manufacturing apparatus 11 according to the present embodiment, main body portion 4 includes a buffer material 4b in contact with first main surface 2a of plate portion 2 and containing carbon. Thereby, when the board part 2 deform | transforms, the buffer material 4b can deform | transform according to a deformation | transformation of the board part 2. FIG. As a result, the stress generated in seed substrate 5 and silicon carbide single crystal 100 fixed to plate portion 2 can be efficiently reduced.

  Furthermore, according to silicon carbide single crystal substrate 100a manufacturing apparatus 11 according to the present embodiment, connecting portion 3 includes an adhesive. Thereby, the board part 2 can be fixed to the main-body part 4 efficiently.

  Furthermore, according to apparatus 11 for manufacturing silicon carbide single crystal substrate 100a according to the present embodiment, connecting portion 3 includes a screw. Thereby, the board part 2 can be fixed to the main-body part 4 efficiently.

  Furthermore, according to silicon carbide single crystal substrate 100a manufacturing apparatus 11 according to the present embodiment, the thermal expansion coefficient at 1000 ° C. of the material constituting plate portion 2 is 0. 0 of the thermal expansion coefficient at 1000 ° C. of silicon carbide. It is 8 times or more and 1.2 times or less. Thereby, the stress which generate | occur | produces in the seed substrate 5 and the silicon carbide single crystal 100 can be reduced efficiently.

  According to the method for manufacturing silicon carbide single crystal substrate 100a according to the present embodiment, thickness T1 of plate portion 2 on which seed substrate 5 is held is smaller than thickness T2 of main body portion 4. Silicon carbide single crystal 100 grown on seed substrate 5 and seed substrate 5 due to the difference in thermal expansion between the material constituting seed substrate 5 and the material constituting plate portion 2 during the growth of silicon carbide single crystal The stress generated in the plate portion 2 is deformed according to the deformation of the seed substrate 5, whereby the stress can be efficiently reduced. Moreover, since the main-body part 4 touches the 1st main surface 2a of the board part 2, the in-plane temperature distribution of the seed substrate 5 fixed on the 2nd main surface 2b of the board part 2 is reduced. As a result, the in-plane distribution of the crystal quality of silicon carbide single crystal substrate 100a obtained by slicing and cutting silicon carbide single crystal 100 grown on seed substrate 5 along a plane perpendicular to the growth direction of silicon carbide single crystal 100 is reduced. can do. Further, cracks in silicon carbide single crystal substrate 100a can be suppressed.

  Further, according to the method for manufacturing silicon carbide single crystal substrate 100a according to the present embodiment, when thickness T2 of plate portion 2 is t (mm) and diameter d1 of seed substrate 5 is d (mm), t (Mm) is 0.0059 × d (mm) or more and 0.059 × d (mm) or less. If t (mm) is 0.0059 × d (mm) or more, the rigidity of the plate portion 2 for holding the seed substrate 5 can be sufficiently increased. If t (mm) is 0.059 × d (mm) or less, the plate portion 2 can be easily deformed in accordance with the deformation of the seed substrate 5 and the silicon carbide single crystal 100, and the stress of the seed substrate 5 is reduced. It can be sufficiently reduced.

  Furthermore, according to the method for manufacturing silicon carbide single crystal substrate 100a according to the present embodiment, main body portion 4 includes buffer material 4b in contact with first main surface 2a of plate portion 2 and containing carbon. Thereby, when the board part 2 deform | transforms, the buffer material 4b can deform | transform according to a deformation | transformation of the board part 2. FIG. As a result, the stress generated in seed substrate 5 and silicon carbide single crystal 100 fixed to plate portion 2 can be efficiently reduced.

  Furthermore, according to the method for manufacturing silicon carbide single crystal substrate 100a according to the present embodiment, connection portion 3 includes an adhesive. Thereby, the board part 2 can be fixed to the main-body part 4 efficiently.

  Furthermore, according to the method for manufacturing silicon carbide single crystal substrate 100a according to the present embodiment, connection portion 3 includes a screw. Thereby, the board part 2 can be fixed to the main-body part 4 efficiently.

  Furthermore, according to the method for manufacturing silicon carbide single crystal substrate 100a according to the present embodiment, the thermal expansion coefficient at 1000 ° C. of the material constituting plate portion 2 is 0.8 times the thermal expansion coefficient at 1000 ° C. of silicon carbide. It is 1.2 times or less. Thereby, the stress which generate | occur | produces in the seed substrate 5 and the silicon carbide single crystal 100 can be reduced efficiently.

  Furthermore, according to the method for manufacturing silicon carbide single crystal substrate 100a according to the present embodiment, silicon carbide single crystal substrate 100a has a diameter d2 of 100 mm or more. Thereby, silicon carbide single crystal substrate 100a having a diameter of 100 mm or more can be manufactured.

  The embodiment disclosed this time is to be considered as illustrative in all points and not restrictive. The scope of the present invention is defined by the terms of the claims, rather than the description above, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims.

  DESCRIPTION OF SYMBOLS 1 Holding part, 2 board part, 2a 1st main surface, 2b 2nd main surface, 3 connection part, 4 main-body part, 4a rigid body part, 4b shock absorbing material, 4c screw part, 4d wall surface, 4e recessed part, 5 types Substrate, 5a First surface, 5b Second surface, 6 Protrusion, 8 Raw material container, 9 Silicon carbide raw material, 10 Growth vessel, 11 Manufacturing device, 100 Single crystal, 100a Single crystal substrate, T1, T2 thickness, d1, d2 diameter.

Claims (12)

A raw material container;
A seed substrate holding part disposed at a position facing the raw material container,
The seed substrate holding portion includes a plate portion having a first main surface and a second main surface facing each other, a main body portion in contact with the first main surface of the plate portion, and the main body portion. Including a connecting portion to be fixed to
The apparatus for manufacturing a silicon carbide single crystal substrate, wherein the thickness of the plate portion is smaller than the thickness of the main body portion.   The said main-body part is a manufacturing apparatus of the silicon carbide single crystal substrate of Claim 1 containing the buffer material which contact | connects the said 1st main surface of the said board part, and contains carbon.   The said connection part is a manufacturing apparatus of the silicon carbide single crystal substrate of Claim 1 or 2 containing an adhesive agent.   The said connection part is a manufacturing apparatus of the silicon carbide single-crystal substrate of any one of Claims 1-3 containing a screw | thread.   5. The thermal expansion coefficient at 1000 ° C. of the material constituting the plate portion is 0.8 to 1.2 times the thermal expansion coefficient of silicon carbide at 1000 ° C. 5. The manufacturing apparatus of the silicon carbide single crystal substrate of description. A plate portion having a first main surface and a second main surface facing each other, a main body portion in contact with the first main surface of the plate portion, and a connection portion for fixing the plate portion to the main body portion. Preparing a seed substrate holding unit including:
Fixing a seed substrate to the second main surface of the plate portion;
And a step of growing a silicon carbide single crystal on the surface of the seed substrate,
The method for manufacturing a silicon carbide single crystal substrate, wherein the thickness of the plate portion is smaller than the thickness of the main body portion.   When the thickness of the plate portion is t (mm) and the diameter of the seed substrate is d (mm), the thickness t (mm) of the plate portion is 0.0059 × d (mm) or more and 0.059 ×. The manufacturing method of the silicon carbide single-crystal substrate of Claim 6 which is d (mm) or less.   The said main-body part is a manufacturing method of the silicon carbide single crystal substrate of Claim 6 or 7 containing the buffer material which touches the said 1st main surface of the said board part, and contains carbon.   The method for manufacturing a silicon carbide single crystal substrate according to claim 6, wherein the connection portion includes an adhesive.   The method for manufacturing a silicon carbide single crystal substrate according to claim 6, wherein the connection portion includes a screw.   The thermal expansion coefficient at 1000 ° C of the material constituting the plate portion is 0.8 to 1.2 times the thermal expansion coefficient of silicon carbide at 1000 ° C, according to any one of claims 6 to 10. The manufacturing method of the silicon carbide single crystal substrate of description.   The method for manufacturing a silicon carbide single crystal substrate according to any one of claims 6 to 11, wherein the diameter of the silicon carbide single crystal substrate is 100 mm or more.

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