JP2015101503A - Manufacturing method of silicon carbide epitaxial substrate, substrate bearing member, and silicon carbide semiconductor manufacturing device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a manufacturing method of a silicon carbide epitaxial substrate having reduced crystal defect, a substrate bearing member used for the manufacturing method of the silicon carbide epitaxial substrate, and a silicon carbide semiconductor manufacturing device.SOLUTION: The manufacturing method of the silicon carbide epitaxial substrate includes a step (S10) for preparing a base substrate, a step (S20) for discharging the base substrate in the insulated state, and a step (S30) for epitaxially growing silicon carbide on the discharged base substrate after the discharging step (S20).

Description

  The present invention relates to a method for manufacturing a silicon carbide epitaxial substrate, a substrate support member, and a silicon carbide semiconductor manufacturing apparatus, and in particular, a method for manufacturing a silicon carbide epitaxial substrate in which occurrence of crystal defects and the like due to particles is reduced, and the silicon carbide The present invention relates to a substrate support member and a silicon carbide semiconductor manufacturing apparatus used in an epitaxial substrate manufacturing method.

  In recent years, semiconductor devices using silicon carbide (SiC) have been studied. A silicon carbide semiconductor device is manufactured using a silicon carbide epitaxial substrate. Generally, a silicon carbide epitaxial substrate is manufactured by epitaxially growing silicon carbide on a base substrate made of silicon carbide.

  The quality of the silicon carbide epitaxial substrate is directly related to the quality and yield of the silicon carbide semiconductor device. One of the important indices for the quality of the silicon carbide epitaxial substrate is crystal defects.

  JP-A-2008-159740 discloses that cleaning of SiC crystal particles by hydrogen gas etching before the SiC single crystal film forming step from the viewpoint of suppressing adhesion of particles from the reaction chamber member of the CVD apparatus to the substrate. A method for producing a SiC single crystal comprising a processing step is described.

JP 2008-159740 A

  However, since it is considered that further miniaturization will progress in the silicon carbide semiconductor device in the future, further reduction of crystal defects is required.

  The present invention has been made to solve the above-described problems. A main object of the present invention is to provide a method for manufacturing a silicon carbide epitaxial substrate with reduced crystal defects, and a substrate support member and a silicon carbide semiconductor manufacturing apparatus used in the method for manufacturing a silicon carbide epitaxial substrate.

  A method of manufacturing a silicon carbide epitaxial substrate according to the present invention includes a step of preparing a base substrate, a step of removing static electricity in the insulated state of the base substrate, and an epitaxial growth of silicon carbide on the removed base substrate after the step of removing electricity And a step of performing.

  A substrate support member according to the present invention has a first surface on which a base substrate can be placed and a second surface located on the opposite side of the first surface, and is made of a conductor. And a connection terminal portion provided on the second surface for electrically connecting the main body portion and the outside.

  A silicon carbide semiconductor manufacturing apparatus according to the present invention includes an insulating member for mounting a base substrate, and a static elimination member attached to the insulating member and provided so that the base substrate can be neutralized.

  ADVANTAGE OF THE INVENTION According to this invention, the manufacturing method of the silicon carbide epitaxial substrate with which the crystal defect was reduced, the board | substrate support member used for the manufacturing method of this silicon carbide epitaxial substrate, and a silicon carbide semiconductor manufacturing apparatus can be provided.

It is a figure for demonstrating the silicon carbide semiconductor manufacturing apparatus which concerns on Embodiment 1. FIG. It is a figure for demonstrating the silicon carbide semiconductor manufacturing apparatus which concerns on Embodiment 1. FIG. It is a figure for demonstrating the silicon carbide semiconductor manufacturing apparatus which concerns on Embodiment 1. FIG. 4 is a diagram for explaining a substrate support member according to Embodiment 1. FIG. 3 is a flowchart of a method for manufacturing a silicon carbide epitaxial substrate according to the first embodiment. It is a figure for demonstrating the silicon carbide semiconductor manufacturing apparatus which concerns on Embodiment 2. FIG. FIG. 11 is a diagram for illustrating the method for manufacturing the silicon carbide epitaxial substrate according to the third embodiment.

  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.

[Description of Embodiment of Present Invention]
First, the outline of the embodiment of the present invention will be enumerated.

  As a result of intensive studies by the inventors of the present application, it has been confirmed that in a conventional method for manufacturing a silicon carbide epitaxial growth substrate, a base substrate prepared before epitaxial growth may be charged to about several keV. In this case, for example, even if the above manufacturing method is performed in a clean environment in order to reduce particles in the work environment, the particles are likely to adhere to the base substrate, and the particles are a cause of crystal defects in the silicon carbide epitaxial substrate. It is thought that it becomes. The inventors of the present application considered that the crystal defects of the silicon carbide epitaxial substrate can be further suppressed by preventing the base substrate from being charged, and completed the method for manufacturing the silicon carbide epitaxial substrate according to the present embodiment. .

  (1) The method for manufacturing a silicon carbide epitaxial substrate according to the present embodiment includes a step of preparing base substrate 1 (S10), a step of removing static electricity from base substrate 1 in an insulated state (S20), and a step of removing static electricity (S20). ), And a step (S30) of epitaxially growing silicon carbide on the base substrate 1 that has been neutralized.

  In this specification, “static elimination” refers to lowering the potential generated by electrostatic charge.

  Further, in this specification, the substrate support member 11 refers to a wafer carrier that is put in a state where the base substrate 1 is placed in the transfer chamber of the silicon carbide semiconductor manufacturing apparatus 100, or the growth chamber R5 of the silicon carbide semiconductor manufacturing apparatus 100. It includes a wafer tray or the like that is loaded with the base substrate 1 placed thereon.

  In this way, before the silicon carbide is epitaxially grown on the base substrate 1 (step (S30)), the base substrate 1 is discharged in an insulated state (step (S20)), thereby reliably removing the charge from the base substrate 1. be able to. The base substrate 1 is charged by disposing the base substrate 1 in the growth chamber R <b> 5 of the silicon carbide semiconductor manufacturing apparatus 100 while maintaining the state where the base substrate 1 is neutralized even after the static elimination of the base substrate 1. Can be suppressed. As a result, according to the method for manufacturing a silicon carbide epitaxial substrate according to the present embodiment, particles can be prevented from adhering to base substrate 1, and therefore, a silicon carbide epitaxial layer epitaxially grown on base substrate 1. It is possible to suppress the occurrence of crystal defects due to particles. In other words, the silicon carbide epitaxial substrate obtained by the method for manufacturing the silicon carbide epitaxial substrate according to the present embodiment has reduced crystal defects.

  (2) In the method for manufacturing a silicon carbide epitaxial substrate according to the present embodiment, the step (S20) of neutralizing the base substrate 1 and the substrate support member with the base substrate 1 mounted on the substrate support member 11 11 may be neutralized in an insulated state.

  In this way, even when epitaxial growth is performed on the base substrate 1 in a state where the base substrate 1 is mounted on the substrate support member 11 in the silicon carbide semiconductor manufacturing apparatus 100, before the growth step (S30). In addition, the base substrate 1 and the substrate support member 11 on which the base substrate 1 is mounted can be discharged simultaneously. Therefore, generation of crystal defects in the silicon carbide epitaxial layer due to particles adhering to base substrate 1 can be suppressed, and a silicon carbide epitaxial substrate with reduced crystal defects can be obtained.

  (3) In the method for manufacturing a silicon carbide epitaxial substrate according to the present embodiment, the step (S20) of neutralizing includes the step (S22) of mounting base substrate 1 on substrate support member 11 and the step of mounting (S22). A step (S21) of discharging the base substrate 1 in an insulated state before the step (S23) and a step (S23) of discharging the base substrate 1 and the substrate support member 11 in an insulated state after the mounting step (S22) may be included.

  In this case, for example, when base substrate 1 is housed in a wafer cassette or the like and is put into silicon carbide semiconductor manufacturing apparatus 100, substrate support member 11 such as a wafer tray in silicon carbide semiconductor manufacturing apparatus 100. Even when the base substrate 1 is mounted on the base substrate 1, the base substrate 1 can be reliably discharged before the step (S30). Specifically, for example, when the base substrate 1 that has been neutralized in the step (S21) is mounted on the substrate support member 11, the base substrate 1 and the substrate support member are caused by friction between the base substrate 1 and the substrate support member 11. Even when 11 is charged, the base substrate 1 and the substrate support member 11 can be reliably discharged in the step (S22). As a result, in step (S30), epitaxial growth can be performed on base substrate 1 in which particle adhesion is suppressed, and a silicon carbide epitaxial substrate with reduced crystal defects can be manufactured.

  (4) The substrate support member 11 according to the present embodiment has a first surface on which the base substrate 1 can be placed and a second surface located on the opposite side of the first surface. And a main body portion 11A made of a conductor and a connection terminal portion 11B provided on the second surface for electrically connecting the main body portion and the outside.

  In this manner, in the method for manufacturing the silicon carbide epitaxial substrate according to the present embodiment, for example, even when the substrate support member 11 is charged after the step (S20) and before the step (S30). In the silicon carbide semiconductor manufacturing apparatus, when the substrate support member 11 is placed, the substrate support member 11 can be easily neutralized by using a ground line provided so as to be able to contact the connection terminal portion 11B.

  (5) In the board | substrate support member 11 which concerns on this Embodiment, the connection terminal part 11B may be provided in the center part of the 2nd surface.

  In this way, silicon carbide semiconductor manufacturing apparatus 100 used in the method for manufacturing the silicon carbide epitaxial substrate according to the present embodiment grows base substrate 1 and substrate support member 11 on which base substrate 1 is mounted. Even when the substrate support member 11 is provided so as to be put into the chamber R5 (that is, when the substrate support member 11 is configured as a wafer tray), the central portion of the second surface of the substrate support member 11 is grown during the epitaxial growth. It is not expressed in the room R5. As a result, even if the substrate support member 11 is placed under epitaxial growth conditions together with the base substrate 1, the material constituting the connection terminal portion is mixed into the silicon carbide epitaxial substrate by volatilizing, precipitating, etc. in the growth chamber R5. Can be prevented.

  (6) Silicon carbide semiconductor manufacturing apparatus 100 according to the present embodiment is provided with insulating member 21 for mounting base substrate 1 and insulating member 21, and is provided so that the base substrate 1 can be neutralized. The static elimination member 31 is provided.

  If it does in this way, this base substrate 1 can be neutralized by the static elimination member 31 with respect to the base substrate 1 which is arrange | positioned on the insulating member 21 and is in the insulated state. Thereby, step (S20) and step (S30) in the method for manufacturing a silicon carbide epitaxial substrate according to the present embodiment can be performed in silicon carbide semiconductor manufacturing apparatus 100. As a result, for example, the process (S20) and the process (S30) can be performed with higher efficiency than in the case where the process is performed manually by an operator, and the charge can be reliably removed before epitaxial growth. Moreover, silicon carbide semiconductor manufacturing apparatus 100 according to the present embodiment can be easily prepared by providing insulating member 21 and static elimination member 31 in conventional silicon carbide semiconductor manufacturing apparatus 100.

  (7) Silicon carbide semiconductor manufacturing apparatus 100 according to the present embodiment further includes a first processing chamber (R7) for processing base substrate 1, and the first processing chamber is for mounting base substrate 1. The first insulating member (27) and the first charge eliminating member (37) attached to the first insulating member (27) may be included.

  In this way, before the base substrate 1 is placed in the growth chamber R5 of the silicon carbide semiconductor manufacturing apparatus 100, the base substrate 1 is processed in the first processing chamber (R7), so that the base substrate 1 is insulated. The static electricity can be removed. For example, the first processing chamber (R7) is a transfer chamber for transferring the base substrate 1 to the second processing chamber (R1), and the first insulating member (27) is provided as a transfer arm. May be. The first static elimination member (37) is provided so as to be able to eliminate static electricity by supplying positive and negative ions to the base substrate 1 mounted on the first insulating member (27) as a transfer arm, for example. It has been. In this case, the base substrate 1 can be discharged at the same time as the base substrate 1 is transported. As a result, the base substrate 1 after neutralization is transferred from the load lock chamber R6 to the growth chamber R5 while maintaining the neutralized state, thereby epitaxially growing the base substrate 1 in which particle adhesion is suppressed. And a silicon carbide epitaxial substrate with reduced crystal defects can be manufactured.

  (8) The silicon carbide semiconductor manufacturing apparatus 100 according to the present embodiment further includes a second processing chamber (static elimination chamber R1) for processing in a state where the base substrate 1 is mounted on the substrate support member 11, and the second processing chamber The chamber (R1) has a second insulating member (21) for placing the substrate supporting member 11 on which the base substrate 1 is mounted, and a second charge eliminating member attached to the second insulating member (21). And a member (31).

  In this way, for example, in silicon carbide semiconductor manufacturing apparatus 100 provided so that base substrate 1 and substrate supporting member 11 on which base substrate 1 is placed are put together in growth chamber R5, base substrate 1 and The substrate support member 11 on which it is mounted can be discharged at the same time. As a result, the base substrate 1 and the substrate support member 11 after neutralization are transported from the second processing chamber (R1) to the growth chamber R5 while maintaining the neutralized state, whereby the adhesion of particles is suppressed. Epitaxial growth can be performed on substrate 1, and a silicon carbide epitaxial substrate with reduced crystal defects can be manufactured. The transport mechanism for transporting from the second processing chamber (R1) to the growth chamber R5 only needs to have an arbitrary configuration, but is preferably composed of a conductive member and grounded.

[Description of Embodiment of Present Invention]
Next, details of the embodiment of the present invention will be described.

  First, referring to FIGS. 1 to 3, a silicon carbide semiconductor manufacturing apparatus according to the present embodiment will be described. Silicon carbide semiconductor manufacturing apparatus 100 according to the present embodiment is an apparatus that enables epitaxial growth of silicon carbide on base substrate 1, and is, for example, a CVD (Chemical Vapor Deposition) apparatus. The CVD apparatus 100 mainly includes a static elimination chamber R1 as a second static elimination chamber, an elevating greenhouse R3, and a growth chamber R5. Further, the CVD apparatus 100 includes a transfer chamber R2 provided with a transfer arm 42 for transferring the substrate support member 11 between the static elimination chamber R1 and the lift greenhouse R3, a lift greenhouse R3, and a growth chamber R5. A transfer chamber R4 in which a transfer arm 44 for transferring the substrate support member 11 is provided. One transfer arm and transfer chamber may be provided between the static elimination chamber R1, the elevating greenhouse R3, and the growth chamber R5. In this case, it is possible to directly transfer between the static elimination chamber R1 and the growth chamber R5.

  The static elimination chamber R <b> 1 is a so-called load lock chamber for introducing, for example, the substrate support member 11 on which the base substrate 1 is mounted into the silicon carbide semiconductor manufacturing apparatus 100. In the static elimination chamber R1, an insulating member 21 having an insulating property is provided. The neutralization member 31 may be any member that can neutralize the base substrate 1 and the substrate support member 11 by an arbitrary method. For example, the neutralization member 31 is configured as an ionizer that generates positive and negative ions.

  In the static elimination chamber R1, the substrate support member 11 on which the base substrate 1 is mounted is placed on the insulating member 21. At this time, the insulating member 21 may be provided so that a single substrate support member 11 can be placed thereon, or may be provided so that a plurality of substrate support members 11 can be placed thereon. The insulating member 21 may be provided in a cassette shape, for example. In addition, the substrate support member 11 placed on the insulating member 21 may be mounted with one or more base substrates 1.

  The transfer chamber R2 is connected to the static elimination chamber R1 through a vacuum valve (gate valve) and is connected to the elevating greenhouse R3. The transfer chamber R2 is provided with a transfer arm 42. The transfer arm 42 is made of a conductive material at least in contact with the connection terminal portion 11B of the substrate support member 11, and this portion is grounded. Has been. When the static elimination chamber R1 reaches a predetermined degree of vacuum and the vacuum valve is opened, the static elimination chamber R1, the transfer chamber R2, and the elevating greenhouse R3 constitute a series of spaces. At this time, the substrate supporting member 11 on which the base substrate 1 is mounted can be transported from the static elimination chamber R1 to the elevating greenhouse R3 by the transport arm 42.

  The elevating greenhouse R3 is provided so that it can be heated to a predetermined temperature while the base substrate 1 is kept neutralized before epitaxial growth. Further, the base substrate 1 is provided so as to be cooled to a predetermined temperature after the epitaxial growth. Specifically, the base substrate 1 is temporarily heated on the conductive member 43 that is grounded in the elevating greenhouse R3. The elevating greenhouse R3 is kept at a predetermined degree of vacuum in a normal use state and is not opened to the atmosphere.

  The transfer chamber R4 is connected to the elevating greenhouse R3 and is connected to the growth chamber R5 via a vacuum valve (gate valve). The transfer chamber R4 is provided with a transfer arm 44. The transfer arm 44 is made of a conductive material at least in contact with the connection terminal portion 11B of the substrate support member 11, and this portion is grounded. Has been.

  The growth chamber R5 is provided so that silicon carbide can be epitaxially grown on the base substrate 1. Specifically, referring to FIGS. 2 and 3, base substrate 1 is mounted on heating element 12 in a state where it is mounted on substrate support member 11 in growth chamber R <b> 5. The board | substrate support member 11 is arrange | positioned in the recessed part formed in the heat generating body 12, for example. The substrate support member 11 is provided so as to be capable of rotating in a state of being disposed on the heating element 12. The heating element 12 has a semi-cylindrical hollow structure, and has a curved surface and a flat surface along an arc. In the CVD apparatus 100, the two heating elements 12 are arranged so that the flat surfaces are opposed to each other, thereby forming a growth chamber R5 surrounded by the flat surfaces of the heating elements 12. The recess is provided on one flat surface of the heating element 12 forming the growth chamber R5.

  The heat insulating material 13 is disposed so as to surround the outer periphery of the heating element 12. The quartz tube 14 is disposed so as to surround the outer peripheral side of the heat insulating material 13. The induction heating coil 15 includes a plurality of coil members, and is provided so as to wind, for example, the outer peripheral side of the quartz tube 14. When the induction heating coil 15 is used as a high frequency coil and a high frequency current is passed through it, the heating element 12 is induction heated by electromagnetic induction. As a result, the base substrate 1 and the source gas supplied to the base substrate 1 can be heated to a predetermined temperature. The substrate support member 11 and the heating element 12 are preferably conductive members having high heat resistance, and are composed of members having a very low nitrogen concentration.

  Next, the substrate support member 11 according to the present embodiment will be described with reference to FIG. The substrate support member 11 according to the present embodiment is provided so that the base substrate 1 can be mounted on the heating element 12 when silicon carbide is epitaxially grown on the base substrate 1. That is, the substrate support member 11 is configured to withstand the epitaxial growth conditions of silicon carbide.

  The substrate support member 11 has a first surface P3 on which the base substrate 1 can be placed and a second surface P4 located on the opposite side of the first surface P3, and is made of a conductor. 11 A of main body parts and the connection terminal part 11B provided in the 2nd surface P4 for electrically connecting the main body part 11A and the exterior are provided.

  The main body 11A of the substrate support member 11 is made of, for example, a carbon material, and preferably a portion made of the carbon material is coated with tantalum carbide (TaC), silicon carbide (SiC), or the like at least on the first surface P3 side. The structure is covered with a film. Connection terminal portion 11B is preferably made of a good conductor, for example, a carbon material is exposed. The main body 11A is exposed in the growth chamber R5 when the substrate support member 11 is disposed in the growth chamber R5. On the other hand, the connection terminal portion 11B does not appear in the growth chamber R5 because it is in contact with the heating element 12 when the substrate support member 11 is disposed in the growth chamber R5. Further, as described above, the connection terminal portion 11B is provided so as to be in contact with the conductive member that is grounded in the transfer arm 42 when the substrate support member 11 is mounted on the transfer arm 42.

  Next, with reference to FIG. 5, the manufacturing method of the silicon carbide epitaxial substrate which concerns on this Embodiment is demonstrated. The method for manufacturing the silicon carbide epitaxial substrate according to the present embodiment includes a step of preparing base substrate 1 (S10), a step of removing static electricity from base substrate 1 in an insulated state (S20), and a step of removing static electricity (S20). And a step (S30) of epitaxially growing silicon carbide on the base substrate 1 that has been neutralized.

  First, a base substrate 1 (see FIG. 5) having a lower surface P1 and an upper surface P2 and made of single crystal silicon carbide is prepared (step (S10)). The lower surface P1 is, for example, a Si surface, and the upper surface P2 is, for example, a C surface. The base substrate 1 may be accommodated in a wafer case made of any material, for example, and the wafer case may be housed in a packaging container made of any material. After the base substrate 1 is taken out from the wafer case, the base substrate 1 is prepared by cleaning with an organic solvent or an acidic solvent. A plurality of base substrates 1 may be prepared, or may be accommodated in a wafer carrier or the like (a member different from a substrate support member 11 described later) made of an arbitrary material.

  The prepared base substrate 1 is mounted on the substrate support member 11 so that the lower surface P1 and the first surface P3 of the substrate support member 11 face each other, and is charged into the static elimination chamber R1 of the silicon carbide semiconductor manufacturing apparatus 100. The

  Next, the base substrate 1 is neutralized in an insulated state (step (S20)). Specifically, the substrate support member 11 on which the base substrate 1 is mounted is placed on the insulating member 21 in the static elimination chamber R1 of the silicon carbide semiconductor manufacturing apparatus 100, and positive and negative ions are generated by the static elimination member 31. Thus, the base substrate 1 and the substrate support member 11 are neutralized.

Next, silicon carbide is epitaxially grown on the base substrate 1 that has been neutralized (step (S30)). Specifically, first, the base substrate 1 and the substrate support member 11 that have been neutralized in the previous step (S20) are transported from the static elimination chamber R1 to the elevating greenhouse R3 by the transport arm 42 made of a conductor and grounded. The base substrate 1 and the substrate support member 11 are heated to a predetermined temperature. At this time, the member in contact with the substrate support member 11 in the elevating greenhouse R3 is composed of a conductive member and is grounded. Next, the heated base substrate 1 and the substrate support member 11 are transferred from the ascending / descending greenhouse R3 to the growth chamber R5 by the transfer arm 44 which is provided in the transfer chamber R4 and is made of a conductor and is grounded. In the growth chamber R5, a source gas used for forming a silicon carbide epitaxial layer is supplied to the base substrate 1 and the base substrate 1 is heated to an epitaxial growth temperature, whereby the upper surface P2 of the base substrate 1 is obtained. A silicon carbide epitaxial layer is formed thereon. The source gas is introduced into the growth chamber R5 through the pipe 16. The source gas contains monosilane (SiH ₄ ), propane (C ₃ H ₈ ), ammonia (NH ₃ ), and the like. In addition to the source gas, a carrier gas containing hydrogen (H ₂ ) is introduced. At this time, any gas is introduced into the growth chamber R5 so as to be sufficiently thermally decomposed when supplied onto the upper surface P2 of the base substrate 1.

  Next, the effect of the silicon carbide epitaxial substrate manufacturing method, the substrate support member, and the silicon carbide semiconductor manufacturing apparatus according to the present embodiment will be described.

  In the method for manufacturing a silicon carbide epitaxial substrate according to the present embodiment, silicon carbide is epitaxially grown on base substrate 1 that is kept in a neutralized state after step (S20) of neutralizing base substrate 1 in an insulated state ( Step (S30)). Therefore, by removing the charge from the base substrate 1, it is possible to suppress the adhesion of particles to the base substrate 1. Since silicon carbide can be epitaxially grown on base substrate 1 in which the adhesion of particles is suppressed, a silicon carbide epitaxial substrate in which the occurrence of crystal defects and the like due to particles is suppressed can be obtained.

  In addition, since the base substrate 1 can be discharged in an insulated state while the base substrate 1 is mounted on the substrate support member 11, the base substrate 1 is mounted on the substrate support member 11 in the silicon carbide semiconductor manufacturing apparatus 100. Even in the case where epitaxial growth is performed on the base substrate 1 in a state where the base substrate 1 is in the state, the base substrate 1 can be reliably discharged before the growing step (S30). Therefore, generation of crystal defects in the silicon carbide epitaxial layer due to particles adhering to base substrate 1 can be suppressed, and a silicon carbide epitaxial substrate with reduced crystal defects can be obtained.

  Silicon carbide semiconductor manufacturing apparatus 100 according to the present embodiment includes insulating member 21, substrate support member 11 placed on insulating member 21 and mounted thereon, in static elimination chamber R <b> 1 as a load lock chamber. The base substrate 1 is provided with a static elimination member 31 provided so that static elimination is possible. Therefore, the base substrate 1 and the substrate support member 11 that are disposed on the insulating member 21 and are in an insulated state can be neutralized by the neutralizing member 31. That is, if base substrate 1 mounted on substrate support member 11 is introduced into silicon carbide semiconductor manufacturing apparatus 100, step (S20) in the method for manufacturing a silicon carbide epitaxial substrate according to the present embodiment is performed in static elimination chamber R1. Can be implemented. Therefore, for example, even when charged base substrate 1 and substrate support member 11 are put into silicon carbide semiconductor manufacturing apparatus 100, particles generated in silicon carbide semiconductor manufacturing apparatus 100 adhere to base substrate 1 and the like. This can be suppressed.

  Furthermore, after silicon carbide semiconductor manufacturing apparatus 100 according to the present embodiment neutralizes base substrate 1 and substrate support member 11, these are transported to growth chamber R <b> 5 while maintaining the neutralization state, and the step (S <b> 30) is performed. be able to. As a result, for example, the base substrate 1 and the substrate support member 11 can be discharged with high efficiency compared to the case where the step (S20) and the step (S30) are performed manually by an operator, and after the charge removal Since the base substrate 1 and the like can be transported to the growth chamber R5 in a vacuum chamber maintained at a predetermined degree of vacuum, particle adhesion can be more effectively suppressed.

  Moreover, silicon carbide semiconductor manufacturing apparatus 100 according to the present embodiment can be easily prepared by providing insulating member 21 and static elimination member 31 in conventional silicon carbide semiconductor manufacturing apparatus 100.

  That is, by performing the method for manufacturing a silicon carbide epitaxial substrate according to the present embodiment using silicon carbide semiconductor manufacturing apparatus 100 according to the present embodiment, a silicon carbide epitaxial substrate with further reduced crystal defects and the like is obtained. be able to.

  The substrate support member 11 according to the present embodiment includes a main body portion 11A made of a conductor and a connection terminal portion 11B that is provided on the second surface P4 and electrically connects the main body portion 11A and the outside. Prepare. Substrate support member 11 can be grounded by connecting terminal portion 11B to a ground line provided in silicon carbide semiconductor manufacturing apparatus 100, for example. That is, since the substrate support member 11 on which the base substrate 1 is mounted is discharged in an insulated state and then transported to the growth chamber R5 by the grounded transfer arms 42 and 44, the base substrate 1 and the substrate support member 11 are The state of being neutralized can be maintained even when placed in the growth chamber R5. For this reason, the adhesion of particles to the base substrate 1 can be suppressed, and the occurrence of crystal defects and the like can be suppressed.

(Embodiment 2)
Next, with reference to FIG. 6, the manufacturing method of the silicon carbide epitaxial substrate which concerns on Embodiment 2, the silicon carbide semiconductor manufacturing apparatus 200, and the board | substrate support member 11 are demonstrated. Silicon carbide epitaxial substrate manufacturing method, silicon carbide semiconductor manufacturing apparatus 200 and substrate support member 11 according to the second embodiment are basically the same as those of silicon carbide epitaxial substrate manufacturing apparatus and silicon carbide semiconductor manufacturing apparatus according to the first embodiment. 200 and the substrate support member 11 are provided. However, in the method for manufacturing a silicon carbide epitaxial substrate, the step (S20) of removing the charge from the base substrate 1 is the step of removing the charge from the base substrate 1 in the insulated state (S21) and the step of removing the base substrate 1 and the substrate support member 11 from each other. The silicon carbide semiconductor manufacturing apparatus 200 includes a second static elimination chamber R7 in which the base substrate 1 itself can be neutralized.

  Specifically, silicon carbide semiconductor manufacturing apparatus 200 according to Embodiment 2 is in an insulated state between load lock chamber R6 in which base substrate 1 housed in a cassette or the like can be placed and base substrate 1 are in an insulated state. A second static elimination chamber R7 provided so as to be capable of static elimination and a mechanism for mounting the base substrate 1 on the substrate support member 11 are further provided. The mechanism to be mounted may be constituted by, for example, an insulating member 27 provided in the second static elimination chamber R7.

  The second static elimination chamber R7 is connected to the load lock chamber R6 and is connected to the static elimination chamber R1. The second charge removal chamber R7 may be provided as a transfer chamber for transferring the base substrate 1 between the load lock chamber R6 and the charge removal chamber R1. The second static elimination chamber R7 is provided with an insulating member 27 that allows the base substrate 1 to be placed in an insulated state. As described above, the insulating member 27 may be configured as a transfer arm that transfers the base substrate 1 put into the load lock chamber R6 to the static elimination chamber R1 and mounts it on the substrate support member 11. Further, the second static elimination chamber R7 is provided with a static elimination member 37 that can neutralize the base substrate 1 placed on the insulating member 27. The method for manufacturing the silicon carbide epitaxial substrate according to the second embodiment is performed using silicon carbide semiconductor manufacturing apparatus 200. The substrate support member 11 according to the second embodiment may have the same configuration as the substrate support member 11 according to the first embodiment.

  In the method for manufacturing a silicon carbide epitaxial substrate according to the second embodiment, first, base substrate 1 prepared in step (S10) is put into load lock chamber R6. Thereafter, the base substrate 1 is mounted on an insulating member 27 provided as a transfer arm, and is transferred to the static elimination chamber R1 through the second static elimination chamber R7. At this time, in the second static elimination chamber R7, The electricity is removed by the electricity removing member 37 while being kept in an insulated state (step (S21)).

  Next, the discharged base substrate 1 is transported to the static elimination chamber R1 by the insulating member 27 and mounted on the substrate supporting member 11 placed on the insulating member 21 (step (S22)). The insulating member 27 that has been transported is again accommodated in the second static elimination chamber R7.

  Next, the base substrate 1 mounted on the substrate support member 11 is neutralized by the neutralizing member 31 while being kept in the insulated state by the insulating member 21 in the neutralizing chamber R1 (step (S23)).

  Then, a silicon carbide epitaxial substrate can be obtained by passing through the process (S30) similar to the manufacturing method of the silicon carbide epitaxial substrate which concerns on Embodiment 1. FIG.

  The method for manufacturing the silicon carbide epitaxial substrate according to the second embodiment is a step of discharging the base substrate 1 and the substrate support member 11 simultaneously in an insulated state (similar to the method for manufacturing the silicon carbide epitaxial substrate according to the first embodiment) ( S23), it is possible to epitaxially grow silicon carbide on the base substrate 1 on which particle adhesion is suppressed in the step (S30), and carbonization in which generation of crystal defects and the like due to particles is suppressed. A silicon epitaxial substrate can be obtained.

  Furthermore, the method for manufacturing the silicon carbide epitaxial substrate according to the second embodiment includes a step (S21) of removing the base substrate 1 alone in an insulated state prior to the step (S22) of mounting the base substrate 1 on the substrate support member 11. Therefore, even when the base substrate 1 is introduced into the silicon carbide semiconductor manufacturing apparatus 200 alone, the base substrate 1 and the substrate support member 11 can be effectively neutralized.

  Thus, even if silicon carbide epitaxial substrate manufacturing method, silicon carbide semiconductor manufacturing apparatus 200, and substrate support member 11 according to the second embodiment are used, the method for manufacturing the silicon carbide epitaxial substrate according to the first embodiment, silicon carbide The same effects as those of the semiconductor manufacturing apparatus 100 and the substrate support member 11 can be obtained.

(Embodiment 3)
Next, a method for manufacturing a silicon carbide epitaxial substrate, a silicon carbide semiconductor manufacturing apparatus 100, and a substrate support member 11 according to Embodiment 3 will be described. Silicon carbide epitaxial substrate manufacturing method, silicon carbide semiconductor manufacturing apparatus 100, and substrate support member 11 according to the third embodiment are basically the same as those of the first embodiment. Although it has the same configuration as the apparatus 100 and the substrate support member 11, the step (S20) of eliminating the charge in the insulated state of the base substrate 1 is not performed in the silicon carbide semiconductor manufacturing apparatus 100, and is performed in a clean environment by an operator. It is different in point.

  Specifically, in the method for manufacturing a silicon carbide epitaxial substrate according to the third embodiment, base substrate 1 prepared in step (S10) is placed on, for example, insulating sheet 23 as shown in FIG. It is mounted on the substrate support member 11 by the operator. At this time, the worker wears an antistatic wristband or the like connected to the ground line 50, for example, and the insulating sheet 23 is placed on a work desk 51 made of a good conductor connected to the ground line 50, for example. Is provided.

  Next, the base substrate 1 and the substrate support member 11 placed on the insulating sheet are neutralized by the operator using the air gun 33 for static elimination / dust removal, and at the same time, the adhered particles and the like are blown away. (Step (S20)).

  After the step (S20), the base substrate 1 and the substrate support member 11 are arranged in the growth chamber R5 of the silicon carbide semiconductor manufacturing apparatus 100 while maintaining the neutralized state. In this case, for example, the base substrate 1 and the substrate support member 11 may be arranged in the growth chamber R5 using a substrate holder (not shown) connected to the ground line by an operator.

  Even if it does in this way, there can exist an effect similar to Embodiment 1. FIG. If it says from a different viewpoint, the manufacturing method of the silicon carbide epitaxial substrate which concerns on Embodiment 3 can utilize the silicon carbide semiconductor manufacturing apparatus 100 which is not provided with the insulating members 21 and 22 and the static elimination members 31 and 32. FIG.

  Similarly to the method for manufacturing the silicon carbide epitaxial substrate according to the second embodiment, the base substrate 1 alone is subjected to charge removal / dust removal in an insulated state, and then mounted on the substrate support member 11 placed on the insulating sheet 23. Then, the base substrate 1 and the substrate support member 11 may be subjected to charge removal / dust removal.

  In the first to third embodiments, the base substrate 1 is subjected to the step (S30) of epitaxially growing silicon carbide while being mounted on the substrate support member 11. However, the present invention is not limited to this. For example, the base substrate 1 may be directly placed on the heating element 12 in the growth chamber R5 and applied to the step (S30). In this case, the same effects as those of the first to third embodiments can be obtained by eliminating the charge of the base substrate 1 alone in an insulated state.

  In the first to third embodiments, the substrate support member 11 may be provided so that a plurality of base substrates 1 can be mounted. Further, the outer diameter of the base substrate 1 can be set to an arbitrary size, for example, 50 mm or more, 100 mm or more, or 150 mm or more. According to the method for manufacturing the silicon carbide epitaxial substrate according to the first to third embodiments, the method can be applied regardless of the outer diameter of base substrate 1 as long as base substrate 1 can be neutralized in an insulated state. .

  Although the embodiment of the present invention has been described as above, the embodiment disclosed this time should 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.

  The present invention is particularly advantageously applied to a method for manufacturing a silicon carbide epitaxial substrate with few crystal defects, a substrate support member used in the method for manufacturing a silicon carbide epitaxial substrate, and a silicon carbide semiconductor manufacturing apparatus.

DESCRIPTION OF SYMBOLS 1 Base substrate 11 Board | substrate support member 11A Main-body part 11B Connection terminal part 12 Heat generating body 13 Heat insulating material 14 Quartz tube 15 Induction heating coil 16 Pipe 21, 22, 27 Insulating member 31, 37 Static elimination member 42, 44 Transfer arm 100 Carbonization Silicon semiconductor manufacturing apparatus P1 Lower surface P2 Upper surface P3 First surface P4 Second surface R1, R7 Static elimination chamber R2, R4 Transfer chamber R3 Lifting greenhouse R5 Growth chamber R6 Load lock chamber

Claims (8)

Preparing a base substrate;
Removing the base substrate in an insulated state; and
And a step of epitaxially growing silicon carbide on the base substrate that has been neutralized after the step of neutralizing.   2. The method of manufacturing a silicon carbide epitaxial substrate according to claim 1, wherein in the step of removing electricity, the base substrate and the substrate support member are removed in an insulated state while the base substrate is mounted on a substrate support member. . The step of neutralizing includes a step of mounting the base substrate on a substrate support member;
Removing the base substrate in an insulated state before the mounting step;
The method for manufacturing a silicon carbide epitaxial substrate according to claim 1, further comprising a step of discharging the base substrate and the substrate support member in an insulated state after the mounting step. A main body having a first surface on which a base substrate can be placed and a second surface located on the opposite side of the first surface, and made of a conductor;
A substrate support member provided on the second surface and provided with a connection terminal portion for electrically connecting the main body portion and the outside.   The substrate support member according to claim 4, wherein the connection terminal portion is provided at a central portion of the second surface. An insulating member for mounting the base substrate;
An apparatus for manufacturing a silicon carbide semiconductor, comprising: a neutralizing member attached to the insulating member and capable of neutralizing the base substrate. A first processing chamber for processing the base substrate;
The first processing chamber includes a first insulating member for placing the base substrate, and a first charge removal member attached to the first insulating member. Silicon carbide semiconductor manufacturing equipment. A second processing chamber for processing the base substrate mounted on a substrate support member;
The second processing chamber includes a second insulating member for mounting the substrate supporting member on which the base substrate is mounted, and a second charge eliminating member attached to the second insulating member. The silicon carbide semiconductor manufacturing apparatus of Claim 6 or Claim 7 containing these.

Images