JP6172669B2 - Susceptor and susceptor cleaning method - Google Patents

Description

  The present invention relates to a susceptor used in a film forming chamber of a silicon carbide film forming apparatus, and a susceptor cleaning method.

A film forming apparatus such as a CVD apparatus or an epitaxial apparatus is an apparatus for growing a thin film on the surface of a predetermined substrate. In such a film forming apparatus, when a thin film is formed, a solid material containing a thin film precursor as a component is deposited on a susceptor on which the substrate is placed. Hereinafter, this solid substance is referred to as a deposit.
As described above, when a deposit is formed on the susceptor, the deposit is peeled off to cause particles, thereby deteriorating the quality of the thin film formed on the surface of the substrate.

  Patent Document 1 discloses an ex-situ dry cleaning in which a member constituting a film forming apparatus to which deposits are attached is taken out and the deposits attached to the members are removed by a dry cleaning apparatus. Has been.

  Specifically, in Patent Document 1, silicon contained in silicon carbide is supplied by supplying a plasma-containing fluorine-containing gas into a processing chamber that houses a member of a silicon carbide film forming apparatus to which silicon carbide is adhered. A first step of removing a component, and a second step of removing a carbon component contained in silicon carbide by supplying a plasma-ized oxygen-containing gas into the processing chamber, A method for removing silicon carbide in which the step and the second step are performed alternately or simultaneously is disclosed.

  By using the method for removing silicon carbide disclosed in Patent Document 1, it is possible to accurately remove the carbon component and silicon component contained in silicon carbide that is the main component of the deposit. In other words, it is possible to accurately remove deposits attached to the members of the silicon carbide film forming apparatus.

JP 2012-182373 A

As described above, by using the method for removing silicon carbide disclosed in Patent Document 1, deposits deposited on the members of the silicon carbide film forming apparatus can be accurately removed.
However, in Patent Document 1, the problem described later occurs.

  FIG. 19 shows a part of a conventional susceptor. FIG. 19A is a perspective view of a conventional susceptor (a cross-sectional view of only the outer peripheral portion of the susceptor), and FIG. 19B is a cross-sectional view of the susceptor in the XX direction shown in FIG. is there.

FIG. 20 is a diagram for explaining a problem of the conventional deposit removal method. FIG. 20A is a cross-sectional view of a susceptor housed in a film forming chamber of a silicon carbide film forming apparatus and on which a silicon carbide substrate is placed. FIG. 20B is a cross-sectional view of a susceptor on which a silicon carbide substrate that is housed in a film forming chamber of a silicon carbide film forming apparatus and on which a silicon carbide film is formed is placed and a deposit is deposited. It is.
FIG. 20C is a cross-sectional view of the susceptor taken out of the film formation chamber of the silicon carbide film formation apparatus and deposits deposited after removing the silicon carbide substrate on which the silicon carbide film is formed. FIG. 20D is a cross-sectional view of the susceptor that is housed in the chamber of the silicon carbide removing device and on which the susceptor protection substrate is placed. FIG. 20E is a cross-sectional view of the susceptor from which deposits have been removed by the silicon carbide removing device.

Next, with reference to FIG. 19 and FIGS. 20A to 20E, a conventional method for removing silicon carbide (deposits) will be described while the conventional method for removing deposits is described. The problem of will be described.
First, a susceptor 300 shown in FIG. 19 is prepared. Here, the configuration of the susceptor 300 will be described.
The susceptor 300 includes a susceptor main body 301 and a substrate housing portion 302 disposed on the surface of the susceptor main body 301. The susceptor body 301 has a disk shape, and a member made of carbon is coated with a film made of a silicon carbide film.
The thickness of the silicon carbide film serving as the coating can be set to 200 μm, for example.

The substrate housing portion 302 has a first recess 302A and a second recess 302B disposed on the surface side of the susceptor body 301.
302 A of 1st recessed parts is the space made into disk shape, and supports a silicon carbide substrate by contacting the surface located in an outer peripheral part among the back surfaces of a silicon carbide substrate.

The inner diameter of first recess 302A is larger than the outer diameter of silicon carbide substrate 305 shown in FIG. 20A and the outer diameter of susceptor protection substrate 311 shown in FIG.
Thereby, gap Y is formed between the outer peripheral edge of the silicon carbide substrate and the side wall of first portion 303A.
As shown in FIG. 20D, when the cleaning process of the susceptor 300 is performed, the susceptor protection substrate 311 is placed in the first recess 302A.

  The second recess 302B is disposed immediately below the first recess 302A, and is integrated with the first recess 302A. The second recess 302B has a disk shape. The inner diameter of second recess 302B is configured to be smaller than the outer diameter of silicon carbide substrate 305 and the outer diameter of susceptor protection substrate 311 shown in FIG.

  The susceptor 300 is composed of one member, not a member composed of a plurality of members that can be disassembled.

  Next, in the process shown in FIG. 20A, the silicon carbide substrate 305 is placed in the first recess 302A of the susceptor 300 housed in a film forming chamber (not shown) of a silicon carbide film forming apparatus (not shown). Is placed. At this stage, a gap Y (for example, 1 to 2 mm) is formed between the outer peripheral edge of silicon carbide substrate 305 and the side wall of first recess 302A.

Next, in the step shown in FIG. 20B, a silicon carbide film 307 is formed on the surface 305a of the silicon carbide substrate 305 by a known method. At this time, a deposit 308 containing silicon carbide as a main component is deposited on the upper surface of the susceptor 300 in which the substrate housing portion 302 is not formed and the bottom surface of the first recess 302A located in the gap Y.
Here, the deposit 308 is a deposit (a deposit made of silicon carbide) that is deposited by repeatedly performing the film forming process of the silicon carbide film, and is not thin, for example, about 20 to 50 μm. Having a thickness of
At this stage, since the deposit 308 is not deposited on the side surface of the first recess 302A, the side surface of the first recess 302A is exposed from the deposit 308.

  Next, in the step shown in FIG. 20C, after the silicon carbide substrate 305 on which the silicon carbide film 307 shown in FIG. 20B is formed is recovered, the film formation chamber (not shown) of the silicon carbide film formation apparatus (not shown). The susceptor 300 on which the deposit 308 is deposited is taken out outside (not shown).

Next, in the step shown in FIG. 20D, the susceptor 300 to which the deposit 308 is attached is housed in a chamber (not shown) of a silicon carbide removing device (not shown). Next, the susceptor protection substrate 311 is placed in the first recess 302 </ b> A of the substrate housing portion 302 of the susceptor 300.
As susceptor protection substrate 311, a substrate having the same shape as silicon carbide substrate 305 (in other words, the same thickness and the same outer diameter) is used.

Next, in a step shown in FIG. 20E, the deposit 308 deposited on the susceptor 300 shown in FIG. 20D is removed by the method disclosed in Patent Document 1.
At this time, the plasma-containing fluorine-containing gas (gas for removing the silicon component contained in the deposit 308) and the plasma-ized oxygen-containing gas (gas for removing the carbon component contained in the deposit 308) ) The directionality is not controlled.
Therefore, the plasma travels not only in the vertical direction from the upper side of the film forming chamber toward the upper surface of the susceptor 300 but also in various directions such as an oblique direction and a lateral direction.

For this reason, the coating 302 located on the side wall of the first recess 302A where the deposit 308 is not deposited is etched by the plasma entering the gap Y and progressing in various directions (the region shown in FIG. 20E). Z), the susceptor 300 is damaged.
For this reason, susceptor 300 after removing deposit 308 cannot be used again in the silicon carbide film forming apparatus.

As described above, the susceptor 300 is not composed of a plurality of detachable (or separable) members, but is composed of one member.
For this reason, the deposit 308 has been removed, and a new susceptor 300 has to be prepared in place of the damaged susceptor 300.
That is, since it is necessary to replace the entire susceptor 300, there is a problem that the manufacturing cost of the silicon carbide film formed on the silicon carbide substrate increases.

  Accordingly, the present invention provides a susceptor capable of reducing the manufacturing cost of a silicon carbide film formed on a silicon carbide substrate by reducing the frequency of replacement of parts of the silicon carbide film forming apparatus, and cleaning the susceptor. It aims to provide a method.

In order to solve the above-mentioned problem, according to the invention according to claim 1, a susceptor used in a film forming chamber of a silicon carbide film forming apparatus, the susceptor main body having a recess on the upper surface side, and the recess A substrate housing member including a housing portion for housing the silicon carbide substrate with a gap interposed between the silicon carbide substrate and the outer peripheral edge of the silicon carbide substrate on which the silicon carbide film is formed. And the substrate housing member is in contact with the back surface of the silicon carbide substrate, so that a support member that supports the silicon carbide substrate and a portion disposed above the support member define the housing portion. with, viewed including the position regulating member, the for regulating the position of the silicon carbide substrate in the plane direction of the silicon carbide substrate, wherein the support member and the position restricting member is a separate body that is separable Provided by featured susceptor It is.

  Moreover, according to the invention which concerns on Claim 2, the said support member has a penetration part which penetrates the center part of this support member, and the said support member is the said penetration part among the back surfaces of the said silicon carbide substrate. The susceptor according to claim 1, wherein the susceptor is in contact with an outer surface.

According to a third aspect of the present invention, the substrate housing member and the susceptor body are each formed by coating a member made of carbon with a film made of silicon carbide. The described susceptor is provided.

According to the invention of claim 4 , the support member, the position regulating member, and the susceptor body are each configured by coating a member made of carbon with a film made of silicon carbide. A susceptor according to claim 1 or 2 is provided.

According to the fifth aspect of the present invention, there is provided a susceptor used in a film forming chamber of a silicon carbide film forming apparatus, wherein the susceptor body having a penetrating portion is detachably disposed on the penetrating portion. And a substrate housing member including a housing portion for housing the silicon carbide substrate with a gap interposed between the silicon carbide substrate and the outer peripheral edge of the silicon carbide substrate, the substrate housing member comprising: The silicon carbide substrate is in contact with the back surface of the silicon carbide substrate, the support member is disposed on the support member, and a gap is interposed between the silicon carbide substrate and the outer periphery of the silicon carbide substrate. A position regulating member that regulates the position of the silicon carbide substrate in the surface direction of the silicon substrate, a plate-like member that is disposed below the support member, supports the support member, and closes one end of the penetrating portion; , only including, the support member, the position Regulating member, and the plate-like member is a separate susceptor, which is a separable is provided.

According to the invention of claim 6 , the substrate housing member is partitioned by the inner wall of the support member and the upper surface of the plate-like member, and the back surface of the silicon carbide substrate housed in the substrate housing member is exposed. A susceptor according to claim 5 is provided.

Further, the invention according to claim 7, wherein the board housing member and the susceptor body, claim, characterized by being composed by coating with a film of composed of carbon each member made of silicon carbide 5 The described susceptor is provided.

According to an eighth aspect of the present invention, there is provided a susceptor cleaning method for removing a deposit made of silicon carbide deposited on a susceptor according to any one of the first to seventh aspects, the method comprising: A step of taking out the susceptor to which the deposit has adhered from a film forming chamber of the film apparatus; and accommodating the susceptor to which the deposit has adhered in the chamber of the silicon carbide removing apparatus, and the accommodating portion of the substrate accommodating member. A susceptor protection substrate that protects the susceptor, an etching step that removes the deposit deposited on the susceptor by dry etching, and the substrate receiving member is damaged after the etching step. Replacing the substrate housing member with another substrate housing member that is not damaged. Training method is provided.

According to the ninth aspect of the invention, the etching step selectively removes the silicon component contained in the deposit by supplying a fluorine-containing gas that has been made plasma into the chamber. And a second step of selectively removing carbon components contained in the deposit by supplying an oxygen-containing gas that has been made plasma into the chamber, and the first step, The susceptor cleaning method according to claim 8, wherein the second step is performed alternately or simultaneously.

According to a tenth aspect of the present invention, there is provided the susceptor cleaning method according to the eighth or ninth aspect, wherein a dummy silicon carbide substrate or a quartz substrate is used as the susceptor protection substrate.

According to the susceptor of the present invention, a gap is interposed between the outer peripheral edge of the silicon carbide substrate on which the silicon carbide film is formed and is detachably arranged with respect to the recess provided in the susceptor body, and the carbonization is performed. By having a substrate accommodating member including an accommodating portion for accommodating a silicon substrate, for example, when the substrate accommodating member is damaged by dry etching when removing deposits made of silicon carbide deposited on the susceptor, the damaged substrate is accommodated. Since only the members need to be replaced (since the susceptor body that occupies most of the susceptor does not have to be replaced), the carbonization formed on the surface of the silicon carbide substrate is compared with the case where the entire susceptor is replaced with a new susceptor. The manufacturing cost of the silicon film can be reduced.
In particular, it is effective in removing a thick deposit deposited on the susceptor by an ex-situ dry cleaning (Ex-Situ).

1 is a plan view of a susceptor according to a first embodiment of the present invention. It is the figure which expanded the part enclosed by the area | region A among the susceptors shown in FIG. 1, (a) is the perspective view (only outer peripheral part of a susceptor is sectional drawing) of the part enclosed by the area | region A, (b ) Is a cross-sectional view of the susceptor shown in FIG. It is sectional drawing to which the susceptor in which the silicon carbide substrate was mounted was expanded. It is the figure which expanded a part of susceptor which concerns on the 1st modification of 1st Embodiment, (a) is a perspective view of a susceptor (only outer peripheral part of a susceptor is sectional drawing), (b) is ( It is sectional drawing of the FF line direction of the susceptor shown to a). It is the figure which expanded a part of susceptor which concerns on the 2nd modification of 1st Embodiment, (a) is a perspective view of a susceptor (only an outer peripheral part of a susceptor is sectional drawing), (b) is ( It is sectional drawing of the GG line direction of the susceptor shown to a). It is the figure which expanded a part of susceptor which concerns on the 3rd modification of 1st Embodiment, (a) is a perspective view of a susceptor, (b) is HH of the susceptor shown to (a). It is sectional drawing of a line direction. It is sectional drawing which shows typically schematic structure of the batch type silicon carbide film-forming apparatus which can use the susceptor of 1st Embodiment. It is sectional drawing which shows typically schematic structure of the single wafer type silicon carbide film-forming apparatus which can use the susceptor which concerns on the 3rd modification of 1st Embodiment. It is a figure which shows schematic structure of the silicon carbide removal apparatus used when performing the cleaning method of the susceptor which concerns on 1st Embodiment. It is sectional drawing of the chamber for demonstrating the structure in the chamber shown in FIG. It is a figure which shows the flowchart for demonstrating the cleaning method of the susceptor which concerns on the 1st Embodiment of this invention. It is a figure for demonstrating each process which comprises the cleaning method of a susceptor. (A) is sectional drawing of the susceptor which the silicon carbide substrate in which the silicon carbide film was formed was collect | recovered, taken out from the film-forming chamber of the silicon carbide film-forming apparatus, and the deposit which consists of silicon carbide deposited. (B) is sectional drawing of the susceptor and the susceptor protection board which were accommodated in the chamber of the silicon carbide removal apparatus, the susceptor protection board was arrange | positioned at the board | substrate accommodation member, and the deposit accumulated. (C) is sectional drawing of a susceptor after a deposit is removed. (D) is a cross-sectional view of a susceptor in which a damaged substrate accommodation member is replaced with a new substrate accommodation member that is not damaged, and then accommodated in a deposition chamber of a silicon carbide deposition apparatus. It is the figure which expanded a part of susceptor which concerns on the 2nd Embodiment of this invention, (a) is a perspective view of a susceptor (only outer peripheral part of a susceptor is sectional drawing), (b) is (a) It is sectional drawing of the II line direction of the susceptor shown in FIG. It is the figure which expanded a part of susceptor which concerns on the 1st modification of the 2nd Embodiment of this invention, (a) is a perspective view of a susceptor (only the outer peripheral part of a susceptor is sectional drawing), (b) FIG. 3 is a cross-sectional view of the susceptor shown in FIG. It is the figure which expanded a part of susceptor which concerns on the 2nd modification of the 2nd Embodiment of this invention, (a) is a perspective view of a susceptor (only the outer peripheral part of a susceptor is sectional drawing), (b) FIG. 3 is a cross-sectional view of the susceptor shown in FIG. It is the figure which expanded a part of susceptor which concerns on the 3rd modification of the 2nd Embodiment of this invention, (a) is a perspective view (only outer peripheral part of a susceptor is sectional drawing) of a susceptor, (b) These are sectional drawings of the LL line direction of the susceptor shown to (a). It is a top view which shows schematic structure of the susceptor used by the comparative example. It is sectional drawing of the MM line direction of the susceptor shown in FIG. It is a figure which shows a part of conventional susceptor. (A) is a perspective view of a conventional susceptor (a sectional view of only the outer peripheral portion of the susceptor), and (b) is a sectional view of the susceptor shown in (a) in the XX line direction. It is a figure for demonstrating the problem of the removal method of the conventional deposit. (A) is sectional drawing of the susceptor in which it accommodated in the film-forming chamber of the silicon carbide film-forming apparatus, and the silicon carbide substrate was mounted. (B) is sectional drawing of the susceptor which the silicon carbide board | substrate with which the silicon carbide film | membrane in which the silicon carbide film | membrane was formed in the film-forming chamber of a silicon carbide film-forming apparatus was mounted is mounted, and the deposit deposited. . (C) is a cross-sectional view of the susceptor taken out of the film forming chamber of the silicon carbide film forming apparatus and deposits deposited after removing the silicon carbide substrate on which the silicon carbide film is formed. (D) is sectional drawing of the susceptor accommodated in the chamber of the silicon carbide removal apparatus, and the susceptor protection board | substrate was mounted. (E) is sectional drawing of the susceptor from which the deposit was removed by the silicon carbide removal apparatus.

  Embodiments to which the present invention is applied will be described below in detail with reference to the drawings. The drawings used in the following description are for explaining the configuration of the embodiment of the present invention. The size, thickness, dimensions, and the like of each part shown in the drawings are the actual susceptor, silicon carbide film forming device, and The dimensional relationship of the silicon carbide removing device may be different.

(First embodiment)
FIG. 1 is a plan view of a susceptor according to a first embodiment of the present invention. C shown in FIG. 1 indicates the center of the susceptor body 11 (hereinafter referred to as “center C”).
2 is an enlarged view of the portion surrounded by the region A in the susceptor shown in FIG. 1, and FIG. 2A is a perspective view of the portion surrounded by the region A (a cross-sectional view of only the outer peripheral portion of the susceptor). 2 (b) is a cross-sectional view of the susceptor shown in FIG. 2 (a) in the DD line direction.
FIG. 3 is an enlarged cross-sectional view of a susceptor on which a silicon carbide substrate is placed. 3 indicates the surface direction of the silicon carbide substrate 30 (in other words, the surface direction of the silicon carbide substrate 30) (hereinafter referred to as “surface direction S”).
In FIG. 1, FIG. 2 (a), (b), and FIG. 3, the same code | symbol is attached | subjected to the same component.

  Referring to FIG. 1, FIG. 2 (a), (b), and FIG. 3, susceptor 10 is a batch type silicon carbide film forming apparatus that forms a silicon carbide film on a plurality of silicon carbide substrates simultaneously. It is a susceptor used in the film forming chamber, and has a susceptor body 11 and a plurality of substrate housing members 12 (eight in the case of FIG. 1).

  The susceptor body 11 is a disk-shaped member, and its outer shape is circular. The susceptor body 11 has a plurality of recesses 14 (eight in the case of FIG. 1) on the upper surface 11a side. The shape of the plurality of recesses 14 is a disk shape that can accommodate the substrate housing member 12. The plurality of recesses 14 are arranged at equal intervals on a circumference B centered on the center C of the susceptor body 11 so that the centers of the plurality of recesses 14 are located.

The susceptor body 11 is configured by coating a member 16 made of carbon with a film 17 (for example, 3C-SiC film) made of silicon carbide. When the outer diameter of the silicon carbide substrate 30 (the substrate on which the silicon carbide film is formed on the surface 30a) placed on the susceptor 10 is 4 inches (102 mm), the portion of the susceptor body 11 where the recess 14 is not formed. The thickness can be 4 mm, for example.
In this case, the thickness of the film 17 can be set to 100 to 200 μm, for example.

The substrate housing member 12 is disposed in each recess 14. The substrate housing member 12 includes a support member 21, a position regulating member 22, and a housing portion 24.
The support member 21 is a ring-shaped member, and has a through portion 21 </ b> A that penetrates the central portion of the support member 21.
The support member 21 is disposed in the recess 14 so as to come into contact with a surface of the bottom surface 14 a of the recess 14 that is located on the outer periphery of the recess 14. The support member 21 protrudes in a direction toward the center of the recess 14 from the position regulating member 22.

  The upper surface of support member 21 protruding in the direction toward center of recess 14 from position regulating member 22 is a surface (in other words, silicon carbide) located on the outer peripheral portion of silicon carbide substrate 30 among rear surface 30b of silicon carbide substrate 30. Of the back surface 30b of the substrate 30, the surface is in contact with the outer surface of the penetrating portion 21A. Thereby, silicon carbide substrate 30 is supported by support member 21.

  As described above, by providing the through portion 21A in the central portion of the support member 21 that supports the silicon carbide substrate 30, even when the silicon carbide substrate 30 is warped by heating, the susceptor body 11 and the substrate housing member 12 The entire silicon carbide substrate 30 can be uniformly heated by radiant heat.

Further, by providing the through portion 21A in the central portion of the support member 21, the back surface 30b of the silicon carbide substrate 30 and the support member 21 (specifically, the first member 21A) are compared with the case where the through portion 21A is not formed. In the case of this embodiment, since the contact area with the coating 32) made of silicon carbide becomes considerably small, transfer of the coating 32 to the back surface 30 b of the silicon carbide substrate 30 can be suppressed.
Further, the contact area between the back surface 30b of the silicon carbide substrate 30 and the coating 32 constituting the support member 21 is considerably reduced, so that the back surface 30b of the silicon carbide substrate 30 is contaminated by impurities (for example, heavy metal) contained in the coating 32. Can be suppressed.

  Support member 21 supports silicon carbide substrate 30 such that surface 30 a of silicon carbide substrate 30 is flush with upper surface 11 a of susceptor body 11.

The position regulating member 22 is a ring-shaped member and is disposed on the support member 21. The position regulating member 22 is accommodated in the recess 14 so as to be close to the inner wall of the recess 14. The position regulating member 22 is configured integrally with the support member 21.
The upper surface 22 a of the position regulating member 22 (in other words, the upper surface 12 a of the substrate housing member 12) is configured to be flush with the upper surface 11 a of the susceptor body 11.

Thereby, the upper surface 12 a of the position regulating member 12 and the surface 30 a of the silicon carbide substrate 30 accommodated in the substrate accommodating member 12 are flush with the upper surface 11 a of the susceptor body 11.
As described above, the upper surface 22a of the position restricting member 22 and the surface 30a of the silicon carbide substrate 30 accommodated in the substrate accommodating member 12 are flush with the upper surface 11a of the susceptor body 11, so that the raw material can be seen from the lateral direction. When a vapor phase growth apparatus (silicon carbide film forming apparatus) for supplying a gas is used, it is possible to suppress the flow of the raw material gas from colliding with the convex portion, so that the plurality of silicon carbide substrates 30 A good silicon carbide film can be formed on surface 30a.

Position restricting member 22 defines accommodating portion 24 in surface direction S and restricts the position of silicon carbide substrate 30 in surface direction S.
The inner diameter of the position regulating member 22 is such that a ring-shaped gap E is formed between the inner wall of the position regulating member 22 and the outer peripheral edge 30 </ b> A of the silicon carbide substrate 30. The magnitude | size of the clearance gap E can be 1-2 mm, for example.

In the substrate housing member 12 having the above-described configuration, a member 31 (one member corresponding to the shape of the support member 21 and the position regulating member 22) made of carbon is coated with a coating 32 made of silicon carbide (for example, 3C-SiC film). It consists of coating.
Thus, the susceptor 10 is heated from below the susceptor 10 by forming the susceptor main body 11 and the substrate housing member 12 by coating the carbon members 16 and 31 with the silicon carbide coatings 17 and 32. Thus, when the silicon carbide substrate 30 is heated by radiant heat, it becomes possible to reduce the difference in heat conduction with respect to the susceptor body 11 and the substrate housing member 12, so that temperature variation in the surface of the silicon carbide substrate 30 is suppressed. Can do.

  The accommodating portion 24 is a disk-shaped space partitioned by the inner wall of the position regulating member 22. Accommodating portion 24 accommodates silicon carbide substrate 30 with gap E interposed between outer peripheral edges 30 </ b> A of silicon carbide substrate 30.

According to the susceptor of the first embodiment, it is detachably disposed with respect to the recess 14 provided in the susceptor body 11, and between the outer peripheral edge 30A of the silicon carbide substrate 30 on which the silicon carbide film is formed. The substrate accommodating member 12 including the accommodating portion 24 that accommodates the silicon carbide substrate 30 with the gap E interposed therebetween, so that the substrate accommodating member is formed by dry etching when removing the deposit made of silicon carbide deposited on the susceptor 10. Since the damaged substrate housing member 12 only needs to be replaced when the 12 is damaged (in other words, the susceptor body 11 occupying most of the susceptor 10 does not need to be replaced), the entire susceptor 10 is replaced with the new susceptor 10. Compared with the case where it is exchanged, the manufacturing cost of the silicon carbide film formed on surface 30a of silicon carbide substrate 30 can be reduced.
In particular, it is effective when removing deposits thickly deposited on the susceptor 10 by exci-site (Ex-Situ) dry cleaning.

FIG. 4 is an enlarged view of a part of the susceptor according to the first modification of the first embodiment, and FIG. 4A is a perspective view of the susceptor (a sectional view of only the outer peripheral portion of the susceptor). FIG. 4B is a cross-sectional view of the susceptor shown in FIG. 4 (a) and 4 (b), the same components as those of the susceptor 10 of the first embodiment shown in FIG.
In FIG. 4A, illustration of silicon carbide substrate 30 shown in FIG. 4B is omitted.

  4A and 4B, a susceptor 35 according to a first modification of the first embodiment is a batch type in which a silicon carbide film is simultaneously formed on a plurality of silicon carbide substrates 30. The susceptor 10 is a susceptor used in the film forming chamber of the silicon carbide film forming apparatus of the first embodiment, except that it has a substrate housing portion 36 instead of the substrate housing portion 12 constituting the susceptor 10 of the first embodiment. It is configured in the same way.

  The substrate housing portion 36 is a substrate except that the substrate housing portion 36 includes a support member 38 and a position restriction member 39 which are separated from each other, instead of the integrated support member 21 and the position restriction member 22 constituting the substrate housing portion 12. The configuration is the same as that of the accommodating portion 12.

The support member 38 is a member having the same shape as the support member 21 shown in FIG. The support member 38 is disposed in the recess 14 so as to come into contact with a surface of the bottom surface 14 a of the recess 14 that is located on the outer periphery of the recess 14.
Support member 38 supports silicon carbide substrate 30 such that surface 30 a of silicon carbide substrate 30 is flush with upper surface 11 a of susceptor body 11.
The support member 38 is configured by coating a member 41 made of carbon with a coating 42 made of silicon carbide (for example, 3C—SiC).

The position restricting portion 39 is a member having the same shape as the position restricting member 22 shown in FIG. The position restricting portion 39 is a member separated from the support member 38. The position restricting portion 39 is a member that can be separated from the support member 38.
The position restricting portion 39 is disposed on the support member 38. The position regulating member 39 is accommodated in the recess 14 so as to be close to the inner wall of the recess 14.

The upper surface 39 a of the position regulating member 39 (in other words, the upper surface 36 a of the substrate housing member 36) is configured to be flush with the upper surface 11 a of the susceptor body 11. The position regulating member 39 is configured by coating a member 44 made of carbon with a coating 45 made of silicon carbide (for example, 3C—SiC).
The upper surface 39 a of the position regulating member 39 and the surface 30 a of the silicon carbide substrate 30 accommodated in the substrate accommodating member 36 are flush with the upper surface 11 a of the susceptor body 11.

According to the susceptor according to the first modification of the first embodiment, the support member 38 that supports the silicon carbide substrate 30 by contacting the outer peripheral portion of the back surface 30b of the silicon carbide substrate 30, and the support member 38 For example, a deposit made of silicon carbide deposited on the susceptor 10 can be separated from the position regulating member 39 that divides the housing portion 24 in which the silicon carbide substrate 30 is housed. When only the position restricting member 39 is damaged when removing the substrate by dry etching, it is only necessary to replace the damaged position restricting member 39 (in other words, it is not necessary to replace the entire substrate housing portion 36). The manufacturing cost of the silicon carbide film formed on the surface 30a of the silicon carbide substrate 30 can be reduced as compared with the case where the entire substrate housing portion 36 is replaced with a new substrate housing portion 36. .
In particular, it is effective when removing deposits thickly deposited on the susceptor 35 by dry cleaning of an ex-situ method (Ex-Situ).

  Further, the support member 38 and the position restricting member 39 are separated from each other, and the support member 38 and the position restricting member 39 are easily formed by making the shapes of the support member 38 and the position restricting member 39 simple ring-shaped members. Can be molded.

FIG. 5 is an enlarged view of a part of a susceptor according to a second modification of the first embodiment, and FIG. 5A is a perspective view of the susceptor (a sectional view of only the outer peripheral portion of the susceptor). FIG.5 (b) is sectional drawing of the GG line direction of the susceptor shown to Fig.5 (a). 5A and 5B, the same components as those in the susceptor 10 according to the first embodiment shown in FIG.
In FIG. 5A, illustration of the silicon carbide substrate 30 shown in FIG. 5B is omitted.

  5A and 5B, a susceptor 50 according to a second modification of the first embodiment is a batch type in which a silicon carbide film is simultaneously formed on a plurality of silicon carbide substrates 30. The susceptor 10 is a susceptor used in the film forming chamber of the silicon carbide film forming apparatus of the first embodiment, except that it includes a substrate housing portion 51 instead of the substrate housing portion 12 constituting the susceptor 10 of the first embodiment. It is configured in the same way.

  The substrate accommodating part 51 is replaced with the integrated supporting member 21 and the position restricting member 22 constituting the substrate accommodating part 12, except that the substrate accommodating part 51 has a supporting member 53 and a position restricting member 54 which are separated from each other. The configuration is the same as that of the accommodating portion 12.

The support member 53 is a ring-shaped member arranged inside the ring-shaped position regulating member 54. The support member 53 is disposed in the recess 14 so as to contact the bottom surface 14 a of the recess 14.
Support member 53 supports silicon carbide substrate 30 such that surface 30 a of silicon carbide substrate 30 is flush with upper surface 11 a of susceptor body 11.
The support member 53 is configured by coating a member 56 made of carbon with a film 57 made of silicon carbide (for example, 3C—SiC).

The position restricting portion 54 is disposed in the concave portion 14 so as to come into contact with the bottom surface 14 a of the concave portion 14 located outside the support member 53. The position restricting portion 54 is a ring-shaped member configured so that its height is equal to the depth of the concave portion 14.
The upper surface 54 a of the position restricting portion 54 (the upper surface 51 a of the substrate housing portion 51) is flush with the upper surface 11 a of the susceptor body 11. The upper surface 54 a of the position restricting portion 54 is a member separated from the support member 53, and is configured to be separable from the support member 53.

  The susceptor 50 according to the second modification of the first embodiment having such a configuration obtains the same effect as the susceptor 35 according to the first modification of the first embodiment described above. Can do.

FIG. 6 is an enlarged view of a part of a susceptor according to a third modification of the first embodiment, FIG. 6A is a perspective view of the susceptor, and FIG. It is sectional drawing of the HH line direction of the susceptor shown to (a). 6 (a) and 6 (b), the same components as those of the susceptor 10 of the first embodiment shown in FIG.
In FIG. 6A, illustration of silicon carbide substrate 30 shown in FIG. 6B is omitted.

6 (a) and 6 (b), a susceptor 65 according to a third modification of the first embodiment is a susceptor used in a film forming chamber of a single wafer silicon carbide film forming apparatus. There is a configuration similar to that of the susceptor 10 except that there is only one substrate accommodating portion 12 and one recess 14 constituting the susceptor 10 of the first embodiment.
The susceptor 65 according to the third modification of the first embodiment having such a configuration can obtain the same effects as the susceptor 10 of the first embodiment.

  FIG. 7 is a cross-sectional view schematically showing a schematic configuration of a batch-type silicon carbide film forming apparatus that can use the susceptor of the first embodiment. In FIG. 7, the same components as those of the susceptor 10 shown in FIG.

  Referring to FIG. 7, a batch type silicon carbide film forming apparatus 70 includes a film forming chamber 71, a stage 73, a first heating unit 75, a first heat insulating member 77, an exhaust port 78, and a rotation. A shaft 79, a rotation drive unit 81, a susceptor receiving member 82, a ceiling plate member 83, a second heating unit 84, a second heat insulating member 85, a third heat insulating member 87, and a source gas outlet unit 89.

Film forming chamber 71 accommodates stage 73, susceptor 10 on which a plurality of silicon carbide substrates 30 are placed, and the end of source gas outlet 89. The film forming chamber 71 has a reaction space 71 </ b> A between the susceptor 10 and the ceiling plate member 83. The stage 73 is disposed at the bottom of the film forming chamber 71.
The first heating unit 75 is installed below the stage 73. First heating unit 75 heats a plurality of silicon carbide substrates 30 to a predetermined temperature by radiant heat and heat conduction of susceptor 10 through first heat insulating member 77, susceptor receiving member 82, and susceptor 10.

The first heat insulating member 77 is provided in the upper part of the stage 73. The 1st heat insulation member 77 is a member for suppressing that the temperature of the heated susceptor 10 falls. The upper surface of the first heat insulating member 77 is exposed from the upper surface of the stage 73.
The exhaust port 78 is provided between the outer peripheral side surface of the stage 73 and the inner wall of the film forming chamber 71. The exhaust port 78 exhausts unnecessary gas existing in the reaction space 71 </ b> A to the outside of the film forming chamber 71.

The rotation shaft 79 is disposed below the stage 73. The rotation shaft 79 has an upper end connected to the center of the stage 73 and a lower end connected to the rotation drive unit 81.
The rotation drive unit 81 rotates the rotation shaft 79 in a predetermined direction, thereby rotating the susceptor 10 fixed on the stage 73 together with the stage 73 via the susceptor receiving member 82.
The susceptor receiving member 82 is a member fixed on the stage 73. The susceptor receiving member 82 is a member for fixing the susceptor 10 in a detachable state.

The ceiling plate member 83 is disposed so as to close the upper end of the film forming chamber 71. The second heating unit 84 is provided in the upper part of the ceiling plate member 83. Second heating unit 84 heats reaction space 71 </ b> A and the plurality of silicon carbide substrates 30 via second and third heat insulating members 85 and 87.
The second heat insulating member 85 is provided in the lower part of the ceiling plate member 83, and the lower surface thereof is exposed from the ceiling plate member 83. The second heat insulating member 85 suppresses the temperature of the lower part of the ceiling plate member 83 heated by the second heating unit 84 from being lowered.

The third heat insulating member 87 is disposed so as to cover the lower surface of the ceiling plate member 83 and the lower surface of the second heating unit 84. The lower surface of the third heat insulating member 87 is exposed by the reaction space 71A. The third heat insulating member 87 suppresses the temperature of the reaction space 71A from decreasing from a predetermined temperature.
The source gas outlet 89 passes through the center of the ceiling plate member 83, and its end is disposed in the reaction space 71A. The source gas outlet 89 is connected to a source gas supply source (not shown). The source gas outlet 89 supplies the source gas supplied from the source gas supply source (not shown) to the reaction space 71A.

  Thereby, a silicon carbide film 90 (for example, a 4H—SiC film) is formed on the surfaces 30 a of the plurality of silicon carbide substrates 30. At this time, a deposit 91 made of silicon carbide (for example, 3C—SiC) is deposited on the upper surface 11a of the susceptor body 11 and the upper surface of the support member 21 exposed in the gap E. The thickness of the deposit 91 is increased by repeatedly performing the film forming process of the silicon carbide film 90 using the same susceptor 10.

  In the silicon carbide film forming apparatus 70 shown in FIG. 7, the susceptor 10 is illustrated as an example of the susceptor. However, instead of the susceptor 10, the second and second embodiments of the first embodiment described above are used. You may use the susceptors 35 and 50 of a 3rd modification.

  FIG. 8 is a cross-sectional view schematically showing a schematic configuration of a single wafer type silicon carbide film forming apparatus in which the susceptor according to the third modification of the first embodiment can be used. In FIG. 8, the same components as those of the susceptor 65 shown in FIG.

  Referring to FIG. 8, a single-wafer silicon carbide film forming apparatus 95 includes a film forming chamber 96, a first heat insulating member 98, a second heat insulating member 99, a susceptor receiving member 101, and a third The heat insulating member 104, the first heating unit 106, and the second heating unit 108 are included.

The film forming chamber 96 accommodates a first heat insulating member 98, a second heat insulating member 99, a susceptor receiving member 101, and a third heat insulating member 104. The film forming chamber 96 has a reaction space 97 between the susceptor 65 and the third heat insulating member 104.
Further, the film forming chamber 96 is disposed on one side wall, is disposed on the other side wall, and is disposed on the other side wall for exhausting unnecessary gas in the reaction space 97. And a gas exhaust port 112 to be used.

The first heat insulating member 98 is provided in the bottom of the film forming chamber 96. The 1st heat insulation member 98 is a member for suppressing that the temperature of the heated susceptor 65 falls.
The second heat insulating member 99 is provided on the ceiling of the film forming chamber 96. The second heat insulating member 99 suppresses the temperature of the heated third heat insulating member 104 from being lowered by the second heating unit 84.

The susceptor receiving member 101 is fixed on the first heat insulating member 98. On the upper surface of susceptor receiving member 101, susceptor 65 on which one silicon carbide substrate 30 is placed is placed. The susceptor 65 is fixed to the susceptor receiving member 101 in a detachable state.
The third heat insulating member 104 is provided on the lower surface of the second heat insulating member 99. The lower surface of the third heat insulating member 104 is exposed by the reaction space 97. The third heat insulating member 104 is a member for suppressing the temperature of the reaction space 97 from decreasing from a predetermined temperature.

The first heating unit 106 is disposed below the film formation chamber 96. First heating unit 106 heats silicon carbide substrate 30 to a predetermined temperature via first heat insulating member 98, susceptor receiving member 101, and susceptor 65.
The second heating unit 108 is disposed above the film formation chamber 96. Second heating unit 108 heats reaction space 97 and silicon carbide substrate 30 to have a predetermined temperature via second and third heat insulating members 99 and 104.

  FIG. 9 is a diagram showing a schematic configuration of a silicon carbide removing apparatus used when performing the susceptor cleaning method according to the first embodiment. FIG. 10 is a cross-sectional view of the chamber for explaining the configuration in the chamber shown in FIG.

Next, silicon carbide removing apparatus 120 will be described with reference to FIGS.
The silicon carbide removing device 120 includes a chamber 121, a stage 123, a heating unit 125, a susceptor receiving member 127, a fluorine-containing gas supply unit 131, an oxygen-containing gas supply unit 132, a plasma generation unit 134, and a vacuum pump. 136, a gas pipe 137, an exhaust gas analysis unit 139, and a control unit 141.
Silicon carbide removing apparatus 120 is a separate apparatus from silicon carbide film forming apparatuses 70 and 95 that form silicon carbide.

The chamber 121 accommodates a stage 123, a heating unit 125, and a susceptor receiving member 127 at the bottom thereof. The chamber 121 has a reaction space 121 </ b> A between the susceptor receiving member 127 and the ceiling of the chamber 121.
A structure (specifically, the susceptor 10 to which the deposit 91 is attached and the susceptor protection substrate 145 is placed) shown in FIG. By supplying the plasma-containing fluorine-containing gas and oxygen-containing gas so as to come into contact with each other, the deposit 91 deposited on the susceptor 10 is removed.
For this reason, the chamber 121 is preferably made of a material having sufficient resistance to the fluorine-containing gas.

The stage 123 is disposed at the bottom of the chamber 121. The heating unit 125 is disposed on the upper side of the stage 123, and its upper surface is exposed from the upper surface of the stage 123.
Heating unit 125 heats the plurality of silicon carbide substrates 30 to a predetermined temperature via susceptor receiving member 127 and susceptor 10 fixed on susceptor receiving member 127. As the heating unit 125, for example, a heater can be used.
Further, the stage 125 may be configured to be rotatable. By rotating the stage 125, the deposit 91 can be removed more uniformly.

By the way, since silicon carbide is chemically very stable, there is no sufficient removal capability simply by contacting with plasma-containing fluorine-containing gas and oxygen-containing gas.
Therefore, by providing the heating unit 125 that heats the susceptor 10 to which the deposit 91 is attached, the reaction between the plasma-containing fluorine-containing gas and oxygen-containing gas and the deposit 91 made of silicon carbide can be promoted.

The heating temperature of the susceptor 10 is preferably 300 ° C. or higher, for example. Heating the susceptor 10 at a very high temperature (for example, a temperature higher than 400 ° C.) is not preferable because the reaction with the susceptor 10 becomes intense.
Further, heating the susceptor 10 at a very high temperature is not preferable because the chamber 121 reacts with the fluorine-containing gas and the oxygen-containing gas (cleaning gas).

  The susceptor receiving member 127 is fixed to the upper surface of the stage 123 and the upper surface of the heating unit 125. The susceptor receiving member 127 is a member that is fixed in a state where the susceptor 10 is detachable.

The fluorine-containing gas supply unit 131 is connected to the plasma generation unit 134. The fluorine-containing gas supply unit 131 supplies a fluorine-containing gas to the plasma generation unit 134. The fluorine-containing gas removes silicon (silicon component) contained in silicon carbide.
Examples of the fluorine-containing gas include fluorine (F ₂ -GWP: 0), hydrogen fluoride (HF-GWP: 0), hydrofluorocarbon (CxHyFz (x, y, z are integers of 1 or more), CH ₃ F- Among GWP-97), one containing at least one can be used.

Examples of the fluorine-containing gas include fluorocarbon (CF ₄ -GWP: 7,390, C ₂ F ₆ -GWP: 12,200), sulfur hexafluoride (SF ₆ -GWP: 22,800), and trifluoride. Nitrogen (NF ₃ -GWP: 17,200), chlorine trifluoride (ClF ₃ -GWP: 0), carbonyl difluoride (COF ₂ -GWP: 1) and the like can also be used.
However, since these gases have a large global warming potential (GWP), they are not so preferable from the viewpoint of global warming. A low environmental load gas such as F ₂ or HF having a small GWP value is preferred.

The oxygen-containing gas supply unit 132 is connected to the plasma generation unit 134. The oxygen-containing gas supply unit 132 supplies an oxygen-containing gas to the plasma generation unit 134.
The oxygen-containing gas supply unit 132 is connected to the plasma generation unit 134 in a state in which only an oxygen-containing gas or an oxygen-containing gas mixed with the fluorine-containing gas supplied from the fluorine-containing gas supply unit 131 can be supplied. Yes. The oxygen-containing gas is a gas that removes carbon (carbon component) contained in silicon carbide.

Examples of the oxygen-containing gas include oxygen (O ₂ ), ozone (O ₃ ), nitrogen oxide (NxOy (x and y are integers of 1 or more)), water vapor (H ₂ O), carbon dioxide (CO ₂ ). , And carbon monoxide (CO), a gas containing at least one gas can be used.

  The plasma generating unit 134 is connected to the fluorine-containing gas supply unit 131 and the oxygen-containing gas supply unit 132. The plasma generator 134 converts the fluorine-containing gas and oxygen-containing gas into plasma, and supplies the plasma-containing fluorine-containing gas and oxygen-containing gas into the chamber 121 (reaction space 121A).

  In order to efficiently convert the fluorine-containing gas and oxygen-containing gas, which are cleaning gases, into plasma, an inert gas such as Ar, He, Ne or the like may be added as a discharge gas to the fluorine-containing gas and the oxygen-containing gas. Good.

  The vacuum pump 136 is connected to the chamber 121 and the gas pipe 137. The vacuum pump 136 exhausts the gas in the chamber 121 and causes the gas pipe 137 to lead out the exhaust gas. The gas pipe 137 is connected to the vacuum pump 136 and the exhaust gas analyzer 139.

  The exhaust gas analyzer 139 is connected to the gas pipe 137. The exhaust gas analyzer 139 is a gas analyzer that measures the concentration of silicon tetrafluoride and / or the concentration of carbon dioxide contained in the exhaust gas. The exhaust gas analysis unit 139 is connected to the control unit 141 and transmits the measured concentration of silicon tetrafluoride or carbon dioxide to the control unit 141.

As the exhaust gas analyzer 139, for example, a non-dispersive infrared analyzer may be used. Thus, by using a non-dispersive infrared analyzer as the exhaust gas analyzer 139, the concentrations of silicon tetrafluoride and carbon dioxide can be measured easily and at low cost.
For example, an analyzer such as a Fourier transform infrared spectrometer, an ultraviolet absorber, a mass spectrometer, or a gas chromatograph may be used as the exhaust gas analyzer 139.

  The control unit 141 is electrically connected to the heating unit 125, the fluorine-containing gas supply unit 131, the oxygen-containing gas supply unit 132, the plasma generation unit 134, and the exhaust gas analysis unit 139.

Control unit 141 performs overall control of silicon carbide removing apparatus 120. For example, based on the concentration of silicon tetrafluoride or the concentration of carbon dioxide transmitted from the exhaust gas analysis unit 139, the control unit 141 generates a plasma generation unit 134, a heating unit 125, a fluorine-containing gas supply unit 131, and an oxygen-containing gas. The supply unit 132 is controlled.
The control unit 141 includes a storage unit and a calculation unit that are not shown. The storage unit stores a silicon tetrafluoride concentration threshold value or a carbon dioxide concentration threshold value inputted in advance.

  In addition, in the calculation unit (not shown), the silicon tetrafluoride concentration threshold value input in advance or the carbon dioxide concentration threshold value and the silicon tetrafluoride generated in the first and second steps described later are used. The chamber 121, the heating unit 125, and the fluorine-containing gas supply unit are stopped so that the processing of the first and second steps is stopped when the concentration or the concentration of carbon dioxide is compared and the concentration is equal to or lower than the threshold value. 131 and the oxygen-containing gas supply unit 132 are controlled.

FIG. 11 is a flowchart for explaining the susceptor cleaning method according to the first embodiment of the present invention.
FIG. 12 is a diagram for explaining each process constituting the susceptor cleaning method. FIG. 12A is a cross-sectional view of a susceptor in which a silicon carbide substrate on which a silicon carbide film is formed is collected, taken out from a film formation chamber of a silicon carbide film formation apparatus, and a deposit made of silicon carbide is deposited. is there.
FIG. 12B is a cross-sectional view of the susceptor that is housed in the chamber of the silicon carbide removing device, the susceptor protection substrate is disposed on the substrate housing member, and the deposit is deposited, and the susceptor protection substrate. FIG. 12C is a cross-sectional view of the susceptor after deposits are removed.
FIG. 12D is a cross-sectional view of the susceptor in which the damaged substrate housing member is replaced with a new substrate housing member that is not damaged, and then housed in the film forming chamber of the silicon carbide film forming apparatus.
In FIG. 12A, silicon carbide substrate 30 and silicon carbide film 90 are indicated by dotted lines. Moreover, in FIG.12 (c), the silicon carbide substrate 30 is shown with a dotted line.

Next, a susceptor cleaning method according to the first embodiment when the silicon carbide removing apparatus 120 shown in FIG. 9 is used will be described with reference to FIGS. 11 and 12A to 12D.
First, when the process shown in FIG. 11 is started, in STEP 1 (step shown in FIG. 12A), a silicon carbide film 90 is formed from the film forming chamber 71 of the silicon carbide film forming apparatus 70 shown in FIG. After collecting the plurality of silicon carbide substrates 30, the susceptor 10 on which the deposit 91 made of silicon carbide is deposited is taken out from the film forming chamber 71. Thereafter, the process continues to STEP2.

At this stage, as shown in FIG. 12A, the deposit 90 is deposited on the upper surface 11a of the susceptor body 11 and the upper surface of the support member 21 exposed in the gap E.
STEP1 can be performed, for example, when the total thickness of the accumulated silicon carbide film 90 exceeds a predetermined threshold (for example, the thickness is 200 μm).

Next, in STEP 2 (step shown in FIG. 12B), the susceptor 10 on which the deposit 91 is deposited is fixed to the susceptor receiving member 127 arranged in the chamber 121 of the silicon carbide removing apparatus 120 shown in FIG.
Next, a susceptor protective substrate 145 having the same shape as that of the silicon carbide substrate 30 is placed on the portion of the substrate housing member 21 where the silicon carbide substrate 30 (FIG. 12) is disposed. Thereafter, the process proceeds to STEP3.

  In this way, by placing the susceptor protective substrate 145 on the substrate housing member 21 on which the silicon carbide substrate 30 (FIG. 12) has been placed, dry etching (to be described later, plasma-modified fluorine-containing gas performed in STEP 3) Etching process using silicon and etching process using oxygenated gas formed into plasma performed in STEP 4) can prevent the coating 17 made of silicon carbide located below the susceptor protection substrate 145 from being etched. .

  Therefore, as a material of the susceptor protective substrate 145, it is preferable to use a material having resistance to plasma-containing fluorine-containing gas and plasma-ized oxygen-containing gas. As such a material, for example, silicon carbide, nitrogen carbide, and sapphire can be used.

  Further, since nitrogen contained in nitrogen carbide and aluminum contained in sapphire are impurities that adversely affect the formation of the silicon carbide film 90, from the viewpoint of impurities, the material of the susceptor protection substrate 145 is high. Single crystal silicon carbide having a purity (purity of 99.9999% or more), polycrystalline silicon carbide, and sintered silicon carbide are more preferable.

As a material for the susceptor protection substrate 145, for example, inexpensive quartz (specifically, synthetic quartz or high purity (purity of 99.9999% or more) fused quartz) may be used. Quartz does not have good resistance to plasma-containing fluorine-containing gas and plasma-ized oxygen-containing gas, but there is no problem of impurities as described above.
For this reason, it is possible to use an inexpensive susceptor protection substrate 145 by forming the susceptor protection substrate 145 with a sufficient thickness using quartz.

  The susceptor protection substrate 145 can be used repeatedly, and when it is damaged, it is replaced with a new susceptor protection substrate 145.

  Next, in STEP 3, a first step of selectively removing silicon contained in the deposit 91 by dry etching for supplying a plasma-containing fluorine-containing gas to the deposit 91 made of silicon carbide deposited on the susceptor 10. To do.

At this time, the plasma-containing fluorine-containing gas is supplied in a direction from the upper side of the chamber 121 to the lower side of the chamber 121, but the plasma-containing fluorine-containing gas is not guided to advance in the vertical direction. For this reason, some of the plasma-containing fluorine-containing gas goes in the vertical direction, and some goes in a direction other than the vertical direction.
In STEP 3, silicon contained in the deposit 91 reacts with the fluorine-containing gas to become silicon tetrafluoride, which is desorbed and removed.

In the first step, the time change of the concentration of silicon tetrafluoride, which is the exhaust gas discharged from the chamber 121, is measured by the exhaust gas analyzer 139, and after the silicon tetrafluoride concentration reaches the maximum value, it is measured 5-10. The process is terminated when the concentration of silicon tetrafluoride continuously changes in the time interval. Thereafter, the process continues to STEP4.
The reason why the concentration of silicon tetrafluoride gradually decreases is that the reaction on the surface of the deposit 91 is reduced and the carbon is increased, thereby preventing the reaction.

  Next, in STEP 4, by supplying a plasma-ized oxygen-containing gas to the deposit 91 made of silicon carbide deposited on the susceptor 10, the carbon contained in the deposit 91 is selectively removed by dry etching. Step 2 is performed.

At this time, the plasma-containing oxygen-containing gas is supplied in a direction from the upper side of the chamber 121 to the lower side of the chamber 121, but the plasma-containing oxygen-containing gas is not induced to advance in the vertical direction. For this reason, some oxygen-containing gases that have been made into plasma are directed in the vertical direction, while others are directed in directions other than the vertical direction.
In STEP 4, the carbon contained in the deposit 91 reacts with the oxygen-containing gas to become carbon dioxide, which is desorbed and removed.

  Further, in the second step, the time change in the concentration of carbon dioxide discharged from the chamber 121 is measured by the exhaust gas analyzer 139, and continuously from 5 to 10 measurement time intervals from when the carbon dioxide concentration reaches the maximum value. The process is terminated when the concentration of carbon dioxide becomes negative. The process then continues to STEP5.

The reason why the concentration of carbon dioxide gradually decreases is that the carbon on the surface of the deposit 91 is reduced and silicon is increased, thereby preventing the reaction.
Further, as the concentration of silicon tetrafluoride and the concentration of carbon dioxide, values obtained by adding arithmetic processing such as moving average may be used. Thereby, it becomes possible to grasp the behavior change of the stable density | concentration.

Next, in STEP 5, it is determined whether or not the concentration of silicon tetrafluoride contained in the exhaust gas has become equal to or lower than a preset threshold value.
In STEP5, when it is affirmatively determined (determined as Yes) that the concentration of silicon tetrafluoride is equal to or lower than a preset threshold value, the process proceeds to STEP6.
Moreover, when the negative determination (determined as No) that the concentration of silicon tetrafluoride is not less than or equal to the preset threshold value is made in STEP 5, the process returns to STEP 3 and the processes of the first and second steps ( Steps 3 and 4) are performed, and the process proceeds to STEP 5 again.

That is, in STEP 5, the first and second steps are repeatedly performed until an affirmative determination is made, thereby removing silicon contained in the deposit 91 made of silicon carbide and removing carbon contained in the deposit 91. Repeat.
In other words, the deposit 91 made of silicon carbide deposited on the susceptor 10 is removed by repeating the first and second steps. Thereby, the upper surface 11a (in other words, the film 17) of the susceptor body 11 is exposed.

  As described above, since the directionality of plasma-containing fluorine-containing gas and oxygen-containing gas is not controlled, it is not protected by the susceptor protection substrate 145 as shown in FIG. In addition, the inner wall of the position regulating member 22 where the deposit 91 is not deposited is damaged by etching.

By the way, when the removal of the deposit 91 approaches the end, the concentration of silicon tetrafluoride generated in the first step and the concentration of carbon dioxide generated in the second step gradually decrease.
Therefore, as described in STEP 5 above, when the concentration of silicon tetrafluoride becomes equal to or lower than a preset threshold value, the processing of the first and second steps is ended, so that the deposits of the susceptor 10 are deposited. The deposit 91 deposited on the susceptor 10 can be accurately removed without damaging the portion covered with the 91.

  Further, as the above-mentioned threshold value of the concentration of silicon tetrafluoride (a preset threshold value), for example, the concentration of silicon tetrafluoride is higher than the maximum value of the concentration of silicon tetrafluoride detected in the first step. A value of 1/10 or less can be used.

  Further, the threshold value of the silicon tetrafluoride concentration is determined in advance by the relationship between the silicon carbide amount of a certain amount and the removal processing speed (the maximum value of the silicon tetrafluoride concentration in the first step, the first and second values). It can be arbitrarily set according to the amount of silicon carbide in the initial stage and the target silicon carbide removal processing amount after grasping the relationship between the concentration of silicon tetrafluoride when the steps are repeated.

  Further, the threshold value of the concentration of silicon tetrafluoride is stored in advance in a control unit 141 (specifically, a storage unit (not shown)) shown in FIG. A comparison is made between the silicon tetrafluoride concentration detected by 139 and the threshold value of the silicon tetrafluoride concentration. Based on this result, the control unit 141 performs the chamber 121, the fluorine-containing gas supply unit 131, and the oxygen-containing concentration. The gas supply unit 132 and the plasma generation unit 134 are controlled.

  In FIG. 11, the case where it is determined in STEP 5 whether or not the concentration of silicon tetrafluoride is equal to or lower than the threshold has been described as an example. In STEP 5, whether the concentration of carbon dioxide is equal to or lower than the threshold. It may be determined whether or not. In this case, it is possible to obtain the same effect as in STEP 5 in which it is determined whether or not the concentration of silicon tetrafluoride is equal to or lower than the threshold value.

As the exhaust gas analyzer 139 for measuring the concentrations of silicon tetrafluoride and carbon dioxide, a non-dispersive infrared analyzer may be used.
In this way, by using a non-dispersive infrared analyzer as the exhaust gas analyzer 139 that measures the concentrations of silicon tetrafluoride and carbon dioxide, the time required to collect one data is several seconds longer if it is short. Since it takes several tens of seconds, the deposit 91 is efficiently removed by providing a response time of 10 measurement time intervals when the data collection time is short and 5 measurement intervals when the data collection time is long. Can be performed.

In the present embodiment, the components generated from the deposit 91 made of silicon carbide are specified as silicon tetrafluoride and carbon dioxide, but one of these is silicon tetrafluoride and carbon dioxide. It occupies most of the product.
Another reason is that the removal reaction conditions for mainly generating silicon tetrafluoride and carbon dioxide are such that the concentration of the fluorine-containing gas component is low, the heating temperature can be set low, and good removal performance is achieved. It is because it can obtain.

  However, for example, when a considerable amount of carbon tetrafluoride is generated by the reaction between the deposit 91 made of silicon carbide and the fluorine-containing gas, carbon tetrafluoride is added to the carbon dioxide as carbon derived from silicon carbide, and the end point is reached. By adjusting the detection and end point detection control mechanisms, the deposit 91 can be removed with higher accuracy.

Next, in STEP 6, the cleaning process (removal process) of the deposit 91 deposited on the susceptor 10 is stopped, and the plurality of susceptor protection substrates 145 placed on the susceptor 10 are collected.
Thereafter, susceptor 10 from which deposit 91 has been removed (susceptor 10 shown in FIG. 12C) is taken out from chamber 121 of silicon carbide removing apparatus 120 shown in FIG. Thereafter, the process proceeds to STEP7.

  Next, in STEP 7, the substrate housing member 12 damaged by the dry etching performed in STEP 3 and 4 among the plurality of substrate housing members 12 is specified. Thereafter, the damaged substrate housing member 12 is replaced with a new substrate housing member 12-1 (an undamaged member (new product) having the same configuration as the substrate housing member 12) (see FIG. 12D).

Next, hydrogen is supplied into the film forming chamber 71 of the silicon carbide film forming apparatus 70 and the susceptor 10 is heated to a predetermined temperature (for example, 1500 ° C.) to perform a heat purge process. Thereafter, the process proceeds to STEP8.
The heating purge process is performed to remove a trace amount of cleaning gas components (specifically, F, N, and O) adhering to the susceptor 10 during cleaning.

In addition to the above method, there are the following two post-treatment methods as the treatment after the heat purge treatment.
As a first post-processing method, hydrogen is supplied into the film forming chamber 71 of the silicon carbide film forming apparatus 70 between STEP 5 and STEP 6 instead of STEP 7, and the susceptor 10 is kept at a predetermined temperature (for example, 1500). There is a method of heating to a temperature of ° C.
As the second post-treatment method, in STEP 7, the susceptor 10 is disposed in a separately prepared heated purge furnace (not shown), hydrogen is supplied into the heated purge furnace, and the susceptor 10 is heated to a predetermined temperature ( For example, there is a method of heating to a temperature of 1500 ° C.

  Next, in STEP 8, the susceptor 10 (the susceptor 10 shown in FIG. 12 (d)) in which the damaged substrate housing member 12 has been replaced is received by the susceptor receiver located in the film forming chamber 71 of the silicon carbide film forming apparatus 70 shown in FIG. Mount on member 82. Thereby, the process shown in FIG. 11 is completed.

According to the susceptor cleaning method of the first embodiment, a step of removing susceptor 10 to which deposit 91 has adhered from film forming chamber 71 of silicon carbide film forming apparatus 70, and chamber 121 of silicon carbide removing apparatus 120 are provided. The susceptor 10 on which the deposit 91 is deposited is accommodated, and the susceptor protective substrate 145 that protects the susceptor 10 is disposed in the accommodating portion 24 of the substrate accommodating member 12 that constitutes the susceptor 10, and dry etching is performed on the susceptor 10. Other substrate housing members that do not damage the damaged substrate housing member 12 when the substrate housing member 21 is damaged after the etching step for removing the deposited deposit 91 and the etching step (steps corresponding to STEPs 3 and 4). 12-1 is replaced, and the deposit 91 is formed by the dry etching. When the non-stacked portion of the substrate housing member 12 is damaged, it is only necessary to replace the damaged substrate housing member 12 with an undamaged substrate housing member 12-1 (in other words, the majority of the susceptor 10 is occupied). Since it is not necessary to replace the susceptor body 11), the manufacturing cost of the silicon carbide film 90 formed on the silicon carbide substrate 30 can be reduced as compared with the case where the entire susceptor 10 is replaced with a new susceptor 10. .
In particular, it is effective when removing deposits thickly deposited on the susceptor 10 by exci-site (Ex-Situ) dry cleaning.

  In the susceptor cleaning method according to the first embodiment, as shown in FIG. 11, as an example, the deposit 91 is removed by alternately performing the first step and the second step. As described above, the deposit 91 may be removed by simultaneously performing the first and second steps. In this case, the concentration of silicon tetrafluoride contained in the exhaust gas is measured continuously from the start of the first and second steps, and it is determined whether or not the concentration of silicon tetrafluoride has become a predetermined threshold value or less. Done.

As described above, when the deposit 91 is removed by simultaneously performing the first and second steps, the susceptor cleaning method according to the first embodiment described above (the cleaning method including the processing shown in FIG. 11). ) Can be obtained.
That is, in the susceptor cleaning method of the present embodiment, the first and second steps may be performed alternately or simultaneously.

  11 and 12, the case where the deposit 91 deposited on the susceptor 10 shown in FIGS. 1 and 2 is removed has been described as an example. However, instead of the susceptor 10, the support member 38 and the position shown in FIG. Any one of the susceptor 35 in which the regulating member 39 is separated, the susceptor 50 in which the supporting member 53 and the position regulating member 54 are separated in FIG. 5, and the susceptor 65 shown in FIG. 6 is used. In this case, the deposit 91 can be removed by the same method as the susceptor cleaning method of the first embodiment described above.

  Further, when the susceptors 35 and 50 are used, for example, only the damaged position regulating members 39 and 54 need to be replaced instead of replacing the damaged substrate housing members 36 and 51 as a whole (in other words, in this case, Since there is no need to replace support members 38 and 53), the manufacturing cost of silicon carbide film 90 formed on surface 30a of silicon carbide substrate 30 can be further reduced.

  2 and 4 to 6, as an example, the susceptor body 11 and the substrate housing members 12, 36, 51 are configured by coating carbon members with a film made of silicon carbide. As described above, the susceptor body 11 and the substrate housing members 12, 36, 51 may be made of only silicon carbide.

  As described above, when the substrate housing members 12, 36, 51 are made of only silicon carbide, carbon is exposed when the substrate housing members 12, 36, 51 are damaged by dry etching in STEP 3, 4. Therefore, impurities contained in carbon can be prevented from adversely affecting silicon carbide film 90.

(Second Embodiment)
FIG. 13 is an enlarged view of a part of the susceptor according to the second embodiment of the present invention, and FIG. 13A is a perspective view of the susceptor (a sectional view of only the outer periphery of the susceptor). FIG. 13B is a cross-sectional view of the susceptor shown in FIG.
In FIGS. 13A and 13B, the same components as those in the structures shown in FIGS. 2 and 3 are denoted by the same reference numerals. Moreover, in FIG.13 (b), the silicon carbide substrate 30 is shown by the point for convenience of explanation.

  Referring to FIGS. 13A and 13B, the susceptor 150 of the second embodiment is a batch type silicon carbide shown in FIG. 7 in which a silicon carbide film is simultaneously formed on a plurality of silicon carbide substrates. A susceptor used in the film forming chamber 71 of the film forming apparatus 70, and includes a susceptor body 151 and a plurality of substrate housing members 152.

The susceptor body 151 has the same structure as the susceptor 10 except that it has a plurality of through portions 154 instead of the plurality of recesses 14 provided in the susceptor body 11 shown in FIGS. 1 and 2 described in the first embodiment. It is comprised similarly.
The shape of the plurality of through portions 154 is a disk shape that can accommodate the substrate accommodation member 152. The plurality of through portions 154 are arranged at equal intervals on the circumference centering on the center of the susceptor body 151 so that the centers of the plurality of through portions 154 are located.

When the outer diameter of the silicon carbide substrate placed on susceptor 10 is 4 inches (102 mm), the depth of through portion 154 can be set to 2 mm, for example. In this case, the opening diameter of the penetration part 154 can be 110 mm, for example.
The susceptor body 151 is configured by coating a member made of carbon with a film made of silicon carbide (for example, 3C—SiC).

  The substrate housing member 152 is disposed in each through portion 154 in a detachable state. The substrate housing member 152 includes a plate-shaped member 161, a support member 162, a position regulating member 163, and the housing portion 24.

The plate-like member 161 is disposed at the bottom of the penetrating part 154 so as to block the lower end (one end part) of the penetrating part 154. The plate member 161 is a disk-shaped plate material.
The plate member 161 is disposed below the support member 162 and supports the support member 162. The lower surface of the plate-shaped member 161 is flush with the lower surface 151b of the susceptor body 151.
The thickness of the plate-shaped member 161 can be made equal to, for example, the thickness of the susceptor body 11 located below the recess 14 shown in FIG.

  The support member 162 is a ring-shaped member, and is disposed on the outer peripheral portion of the upper surface of the plate-like member 161. The lower end of the support member 162 is integrated with the plate-like member 161. The recess 168 is disposed at the center of the support member 162 and is partitioned by the inner wall of the support member 162 and the upper surface of the plate-like member 161. Recess 168 exposes back surface 30 b of silicon carbide substrate 30 placed on substrate housing member 152.

Upper surface of support member 162 located outside recess 168 is in contact with the surface located on the outer peripheral portion of silicon carbide substrate 30 among back surface 30b (see FIG. 3) of silicon carbide substrate 30.
Thereby, support member 162 supports silicon carbide substrate 30 such that surface 30a of silicon carbide substrate 30 is flush with upper surface 151a of susceptor body 151.

  Position restricting member 163 is a ring-shaped member, and defines accommodating portion 24 in surface direction S of silicon carbide substrate 30. The position regulating member 163 is disposed on the outer peripheral portion of the upper surface of the support member 162. The position regulating member 163 is accommodated in the penetration part 154 so as to be close to the inner wall of the penetration part 154. The lower end of the position regulating member 163 is configured integrally with the support member 162.

Position regulating member 163 regulates the position of silicon carbide substrate 30 in surface direction S with gap E interposed between outer circumferential edge 30 </ b> A of silicon carbide substrate 30.
The upper surface 163a of the position restricting member 163 (in other words, the upper surface 152a of the substrate housing member 152) is configured to be flush with the upper surface 151a of the susceptor body 151.
As a result, the upper surface 163a of the position regulating member 163 is flush with the upper surface 151a of the susceptor body 151.

  The inner diameter of the position regulating member 163 is such that a ring-shaped gap E is formed between the inner wall of the position regulating member 163 and the outer peripheral edge 30 </ b> A of the silicon carbide substrate 30. The magnitude | size of the clearance gap E can be 1-2 mm, for example.

  The accommodating portion 24 is a disk-shaped space partitioned by the inner wall of the position regulating member 163. Accommodating portion 24 accommodates silicon carbide substrate 30 with gap E interposed between outer peripheral edges 30 </ b> A of silicon carbide substrate 30.

  The substrate housing member 152 configured as described above is made of carbon carbide (one member corresponding to the shape of the plate-like member 161, the support member 162, and the position regulating member 163) made of silicon carbide (for example, 3C-SiC). It is comprised by coating with the film which becomes.

According to the susceptor of the second embodiment, the gap E is interposed between the susceptor main body 151 having the penetrating portion 154 and the outer peripheral edge 30A of the silicon carbide substrate 30 on which the silicon carbide film is formed. The contact portion 24 that accommodates the substrate 30 and the back surface 30b of the silicon carbide substrate 30 are in contact with the support member 162 that supports the silicon carbide substrate 30, the support member 162, and the outer peripheral edge 30A of the silicon carbide substrate 30. And a position regulating member 163 that regulates the position of the silicon carbide substrate 30 in the surface direction S of the silicon carbide substrate 30 and a support member 162, and supports the support member 162. And a board accommodating member 152 that includes a plate-like member 161 that closes one end of the penetrating portion 154 and is detachably disposed with respect to the penetrating portion 154. In addition to the case where the substrate housing member 152 is damaged when removing the deposit made of silicon carbide deposited on the stopper 150, for example, by heating by the heating unit 125 (see FIGS. 9 and 10) of the silicon carbide removing device 120. When the plate member 161 is damaged, the silicon carbide substrate 30 can be heated uniformly by replacing the substrate housing member 152 with another substrate housing member 152 that is not damaged.
Thereby, the film quality of the silicon carbide film formed on surface 30a of silicon carbide substrate 30 can be improved.

In particular, it is effective in removing a thick deposit deposited on the susceptor 150 by an ex-situ dry cleaning (Ex-Situ).
The susceptor 150 of the second embodiment can obtain the same effect as the susceptor 10 of the first embodiment.

  Further, the cleaning method for deposits deposited on the susceptor 150 of the second embodiment can be performed by the same method as the cleaning method of the susceptor described in the first embodiment. The same effects as those of the susceptor cleaning method can be obtained.

FIG. 14 is an enlarged view of a part of a susceptor according to a first modification of the second embodiment of the present invention, and FIG. 14A is a perspective view of the susceptor (a sectional view of only the outer peripheral portion of the susceptor). FIG. 14B is a cross-sectional view of the susceptor shown in FIG.
14A and 14B, the same components as those shown in FIGS. 13A and 13B are denoted by the same reference numerals.

14 (a) and 14 (b), a susceptor 170 according to a first modification of the second embodiment is shown in FIG. 7 in which a silicon carbide film is simultaneously formed on a plurality of silicon carbide substrates. A susceptor used in a film forming chamber 71 of a batch type silicon carbide film forming apparatus 70 shown in the drawing, and includes a susceptor main body 151 and a plurality of substrate housing members 171.
That is, the susceptor 170 according to the first modification example of the second embodiment is configured by replacing the substrate accommodation member 152 constituting the susceptor 150 according to the first modification example of the second embodiment with a substrate accommodation member 171. Except having it, it is comprised similarly to the susceptor 150.

  The substrate housing member 171 is described in the second embodiment except that the support member 162 and the position regulating member 163 shown in FIG. 13 are integrated, and the support member 162 and the plate-like member 161 are separated. The configuration is the same as that of the substrate housing member 152.

According to the susceptor 171 according to the first modification of the second embodiment, the support member 162 and the position regulating member 163 are integrated, and the support member 162 and the plate-like member 161 are separated. If the support member 162 or the position restricting member 163 is damaged after the deposit deposited on the susceptor 171 is removed by dry etching, the support member 162 and the support member 162 that do not damage the position restricting member 163 are integrated. When the plate member 161 is damaged by the heating of the heating unit 125 (see FIGS. 9 and 10) of the silicon carbide removing device 120, the plate member 161 is damaged. Since it is possible to replace the plate member 161 that is not provided, the manufacturing cost of the silicon carbide film can be reduced.
In particular, it is effective in removing thick deposits deposited on the susceptor 170 by ex-situ dry cleaning.

FIG. 15 is an enlarged view of a part of a susceptor according to a second modification of the second embodiment of the present invention, and FIG. 15A is a perspective view of the susceptor (a sectional view of only the outer peripheral portion of the susceptor). FIG. 15B is a cross-sectional view of the susceptor shown in FIG.
In FIGS. 15A and 15B, the same components as those shown in FIGS. 14A and 14B are denoted by the same reference numerals.

  Referring to FIGS. 15A and 15B, a susceptor 180 according to a second modification of the second embodiment is a support constituting the susceptor 170 according to the first modification of the second embodiment. The structure is the same as that of the susceptor 170 except that the member 162 and the position regulating member 163 are separated.

  Since the susceptor 180 according to the second modification of the second embodiment having such a configuration divides the substrate housing member 181 into three members, the first modification of the second embodiment. Since it becomes possible to exchange members more finely than the susceptor 170 according to the above, it is possible to further reduce the manufacturing cost.

  Further, the support member 162 and the position restricting member 163 are separated from each other, and the support member 162 and the position restricting member 163 are formed in a simple ring shape, so that the support member 162 and the position restricting member 163 are easily formed. be able to.

FIG. 16 is an enlarged view of a part of a susceptor according to a third modification of the second embodiment of the present invention, and FIG. 16A is a perspective view of the susceptor (a sectional view of only the outer peripheral portion of the susceptor). FIG. 16B is a cross-sectional view of the susceptor shown in FIG.
16A and 16B, the same components as those shown in FIGS. 5A and 5B and FIGS. 15A and 15B are denoted by the same reference numerals.

Referring to FIGS. 16A and 16B, the susceptor 190 according to the third modification of the second embodiment is a support that constitutes the susceptor 180 according to the second modification of the second embodiment. Instead of the member 162 and the position restricting member 163, the structure is the same as that of the susceptor 180 except that the support member 53 and the position restricting member 54 shown in FIGS.
That is, the support member 53 and the position restricting member 54 constituting the susceptor 180 are members that are separated and have a simple ring shape.

  The susceptor 190 according to the third modification of the second embodiment having such a configuration divides the substrate housing member 191 into three members (a support member 53, a position regulating member 54, and a plate-like member 161). Therefore, the same effect as that of the susceptor 180 according to the second modification of the second embodiment can be obtained.

  The cleaning of the deposit made of silicon carbide deposited on the susceptors 170, 180, and 190 according to the first to third modifications of the second embodiment described above is the susceptor described in the first embodiment. This method can be performed by the same method as that of the cleaning method, and the same effect as that of the susceptor cleaning method of the first embodiment can be obtained.

  The preferred embodiments of the present invention have been described in detail above, but the present invention is not limited to such specific embodiments, and within the scope of the present invention described in the claims, Various modifications and changes are possible.

(Example)
<Preparation process of susceptor>
In the example, the susceptor 10 of the first embodiment shown in FIGS. 1 and 2 was used as a susceptor on which a plurality of silicon carbide substrates 30 are placed.
As silicon carbide substrate 30, a single crystal silicon carbide wafer having a diameter of 3 inches (7.62 cm) and a thickness of 350 μm was used.

As the susceptor 10, a carbon member 16 coated with a 200 μm thick silicon carbide film (3C—SiC film (coating film 17)) was used.
Further, the outer diameter of the susceptor body 11 is 300 cm, the thickness of the susceptor body 11 is 3 mm, the diameter of the housing part 24 is 7.82 cm (in other words, the width of the ring-shaped gap E is 1 mm), and the depth of the housing part 24 The same thickness as that of the silicon carbide substrate 30 was 350 μm, and the depth of the through portion 21A was 1 mm.

The surface of the back surface 30b of the silicon carbide substrate 30 and the upper surface of the support member 21 are brought into contact with the housing portion 24 of the susceptor 10 having the above-described configuration, thereby bringing the susceptor into contact with the upper surface of the support member 21. The silicon carbide substrate 30 was placed on the plurality of substrate housing members 12 (specifically, housing portions 24) provided in 10.
At this time, the surface 30 a of the silicon carbide substrate 30 disposed in the plurality of accommodating portions 24 was flush with the upper surface 11 a of the susceptor body 11.

<Silicon Carbide Film Forming Process on Multiple Silicon Carbide Substrates>
Next, susceptor 10 is housed in film forming chamber 71 of silicon carbide film forming apparatus 70 (manufactured by Taiyo Nippon Sanso Corporation) shown in FIG. 7, and silicon carbide film 90 is formed on surfaces 30 a of a plurality of silicon carbide substrates 30. The step of forming (epitaxially growing) a 4H—SiC film having a thickness of 10 μm was repeated 15 times.

At this time, SiH ₄ (supply amount is 240 sccm) and C ₃ H ₈ (supply amount is 180 sccm) were used as source gases. As the carrier gas, H ₂ (supply amount is 1000 sccm) was used. The temperature in the film forming chamber 71 during epitaxial growth was set to 1600 ° C.

  By carrying out the step of forming the 4H—SiC film, it is confirmed that the deposit 91 (see FIG. 12A) made of silicon carbide is deposited in the gap E, and on the upper surface 11a of the susceptor body 11. It was confirmed that a deposit 91 (a deposit made of silicon carbide (3C—SiC)) having a thickness of 200 μm was deposited.

<Cleaning process to remove deposits deposited on susceptor>
Next, susceptor 10 on which deposit 91 was deposited was taken out from silicon carbide film forming apparatus 70 shown in FIG. Next, the susceptor 10 on which the deposit 91 is deposited is fixed on the susceptor receiving member 127 (see FIG. 10) disposed in the chamber 121 of the silicon carbide removing device 120 (manufactured by Taiyo Nippon Sanso Corporation) shown in FIG. Then, a cleaning process for removing the deposit 91 was performed.

  As the cleaning process, the cleaning method described above with reference to FIGS. 11 and 12 is used to supply the plasma-containing fluorine-containing gas into the chamber 121, so that the deposit 91 made of silicon carbide is applied. A first step of selectively removing the contained silicon component; and a second step of selectively removing the carbon component contained in the deposit 91 by supplying a plasma-generated oxygen-containing gas into the chamber 121. By sequentially repeating the steps, the deposit 91 deposited on the susceptor 10 was removed.

At this time, NF ₃ (supply amount was 100 sccm) was used as the fluorine-containing gas, and O ₂ (supply amount was 500 sccm) was used as the oxygen-containing gas. The temperature in the chamber 121 during the cleaning process was set to 300 ° C.

  After the removal of the deposit 91 was completed, it was confirmed that the position regulating member 22 of the susceptor 10 was etched and the thickness of the position regulating member 22 was reduced.

<Replacement of damaged substrate housing member and heating purge process>
Then, as shown in FIG. 12D, the damaged substrate housing member 12 was replaced with a new substrate housing member 12-1 that was not damaged. Thereafter, hydrogen (supply amount 100 sccm) was supplied to the film forming chamber 71 of the silicon carbide film forming apparatus 70, and the susceptor 10 was heated to a temperature of 1500 ° C. to perform a heat purge for 30 minutes.

<Step of Forming Silicon Carbide Film on Multiple Silicon Carbide Substrates after Replacement of Damaged Substrate Housing Member>
Next, the plurality of silicon carbide substrates 30 are placed on the susceptor 10 in which the damaged substrate housing member 12 has been replaced, and the silicon carbide film 91 described above is formed on the surfaces 30 a of the plurality of silicon carbide substrates 30. (Specifically, a process of forming a 10 μm 4H—SiC film 15 times).
In the example, the epi-defect of the 4H—SiC film was not confirmed in the fifteen deposition processes. From this, it was confirmed that a satisfactory 4H—SiC film can be formed by replacing the damaged substrate housing member 12 and reusing the susceptor body 11.

(Comparative example)
<Preparation process of susceptor>
FIG. 17 is a plan view showing a schematic configuration of the susceptor used in the comparative example. 18 is a cross-sectional view of the susceptor shown in FIG. 17 in the MM line direction. In FIG. 18, for convenience of explanation, silicon carbide substrate 30 that is not illustrated in FIG. 17 is illustrated by a dotted line.

In the comparative example, susceptor 250 shown in FIGS. 17 and 18 was used as a susceptor on which a plurality of silicon carbide substrates 30 are placed.
Here, the configuration of the susceptor 250 used in the comparative example will be described with reference to FIGS. 17 and 18.
The susceptor 250 includes a susceptor main body 251 and a plurality of substrate housing portions 252. The plurality of substrate accommodating portions 252 are arranged at equal intervals so that the centers of the substrate accommodating portions 252 are positioned on a circumference centered on the center N of the susceptor body 251.

  Substrate accommodating portion 252 is disposed below first portion 252-1 that is a space in which silicon carbide substrate 30 is disposed, and first portion 252-1 and has an opening diameter that is larger than that of first portion 252-1. And a second portion 252-2 that is a space integrated with the first portion 252-1.

Silicon carbide substrate 30 was placed such that gap P between its outer peripheral edge 30A and the side wall of first portion 252-1 was 1 mm.
First portion 252-1 had an external total of 7.82 cm (in other words, gap P was 1 mm) and a depth of 350 μm, which is the same as the thickness of silicon carbide substrate 30. The depth of the second portion 252-2 was 1 mm.
As the susceptor 250, a carbon member coated with a 200 μm thick silicon carbide film was used.

<Silicon Carbide Film Forming Process on Multiple Silicon Carbide Substrates>
Next, the susceptor 250 is accommodated in the film forming chamber 71 of the silicon carbide film forming apparatus 70 (manufactured by Taiyo Nippon Sanso Corporation) shown in FIG. 7, and a silicon carbide film is formed on the surfaces 30a of the plurality of silicon carbide substrates 30. The process of forming (epitaxially growing) a 4H—SiC film having a thickness of 10 μm was repeated 15 times.
The conditions for forming the 4H—SiC film at this time were the same as in the example.

  By performing the step of forming the 4H—SiC film, it is confirmed that a deposit made of silicon carbide is deposited in the gap P, and a deposit (silicon carbide) having a thickness of 42 μm is formed on the upper surface 251a of the susceptor body 251. It was confirmed that a deposit comprising

<Cleaning process to remove deposits deposited on susceptor>
Next, susceptor 250 on which deposits were deposited was taken out from silicon carbide film forming apparatus 70 shown in FIG. Next, a susceptor in which a deposit made of silicon carbide is deposited on a susceptor receiving member 127 (see FIG. 10) disposed in the chamber 121 of the silicon carbide removing device 120 (manufactured by Taiyo Nippon Sanso Corporation) shown in FIG. 250 was fixed and the cleaning process which removes this deposit was implemented.
As the cleaning conditions at this time, the same conditions as in the example were used.

  After the removal of the deposit was completed, it was confirmed that the side wall of the first portion 252-1 constituting the susceptor 250 was etched to reduce the thickness.

<Heating purge process>
Next, hydrogen (supply amount: 100 sccm) was supplied to the film forming chamber 71 of the silicon carbide film forming apparatus 70, and the damaged susceptor 250 was heated to a temperature of 1500 ° C., thereby performing a heating purge for 30 minutes.

<Step of Forming Silicon Carbide Film on Multiple Silicon Carbide Substrates after Heat Purge>
Next, the plurality of silicon carbide substrates 30 are placed on the damaged susceptor 250, and the same process as the silicon carbide film formation process described above (specifically, the surface 30a of the plurality of silicon carbide substrates 30 is specifically described). A process of forming a 10 μm 4H—SiC film 15 times).
In the comparative example, the epi-defect of the 4H—SiC film was confirmed after the fifth time. This is considered to be because a 4H—SiC film was formed using the damaged susceptor 250.

  The present invention can be applied to a susceptor used in a film forming chamber of a silicon carbide film forming apparatus and a susceptor cleaning method.

10, 35, 50, 65, 150, 170, 180, 190, 250 ... susceptor, 11, 151, 251 ... susceptor body, 11a, 12a, 22a, 36a, 39a, 51a, 54a, 151a, 152a, 163a, 251a ... Upper surface, 12, 12-1, 36, 51, 152, 171, 181, 191 ... Substrate housing member, 14, 168 ... Recess, 14a ... Bottom surface, 16, 31, 41, 44, 56 ... Member, 17, 32 , 42, 45, 57 ... coating, 21, 38, 53, 162 ... support member, 21A ... penetrating part, 22, 39, 54, 163 ... position regulating member, 24 ... accommodating part, 30 ... silicon carbide substrate, 30a ... Front surface, 30b ... Back surface, 30A ... Outer peripheral edge, 70, 95 ... Silicon carbide film forming apparatus, 71, 96 ... Film forming chamber, 71A, 97, 121A ... Reaction space, 73, 123 ... , 75, 106 ... first heating unit, 77,98 ... first heat insulating member, 78 ... exhaust port, 79 ... rotary shaft, 81 ... rotation drive unit, 82,101,127 ... susceptor receiving member, 83 ... Ceiling plate member, 84, 108 ... second heating unit, 85,99 ... second heat insulating member, 87,104 ... third heat insulating member, 89 ... source gas outlet, 90 ... silicon carbide film, 91 ... deposition 111 ... Raw material gas introduction port, 112 ... Gas discharge port, 120 ... Silicon carbide removal device, 121 ... Chamber, 125 ... Heating unit, 131 ... Fluorine-containing gas supply unit, 132 ... Oxygen-containing gas supply unit, 134 ... Plasma Generating part, 136 ... vacuum pump, 137 ... gas pipe, 139 ... exhaust gas analyzing part, 141 ... control part, 145 ... susceptor protection substrate, 151b ... bottom surface, 154 ... penetrating part, 161 ... plate-like member, 252 ... substrate housing part , 52-1 ... first portion, 252-1 ... second part, A ... area, B ... circumference, C, N ... center, E, P ... clearance, S ... surface direction

Claims (10)

A susceptor used in a film forming chamber of a silicon carbide film forming apparatus,
A susceptor body having a recess on the upper surface side;
Substrate accommodation including a housing portion that accommodates the silicon carbide substrate with a gap interposed between the outer periphery of the silicon carbide substrate that is detachably arranged with respect to the recess and on which a silicon carbide film is formed. Members,
Have
The substrate housing member is in contact with the back surface of the silicon carbide substrate, thereby supporting the silicon carbide substrate;
Wherein together with the support portion located above the member partitioning the containing portion, seen including a position regulating member for regulating the position of the silicon carbide substrate in the plane direction of the silicon carbide substrate,
The susceptor, wherein the support member and the position regulating member are separate and separable . The support member has a penetrating portion that penetrates a central portion of the support member;
The susceptor according to claim 1, wherein the support member is in contact with a surface of the back surface of the silicon carbide substrate that is positioned outside the through portion .   2. The susceptor according to claim 1, wherein each of the substrate housing member and the susceptor body is formed by coating a member made of carbon with a film made of silicon carbide. 3. The susceptor according to claim 1, wherein each of the support member, the position restricting member, and the susceptor body is formed by coating a member made of carbon with a film made of silicon carbide. A susceptor used in a film forming chamber of a silicon carbide film forming apparatus,
A susceptor body having a penetrating portion;
A substrate housing member that includes a housing portion that houses the silicon carbide substrate with a gap interposed between the silicon carbide substrate and the outer peripheral edge of the silicon carbide substrate on which the silicon carbide film is formed and is detachably disposed with respect to the through portion. When,
Have
The substrate housing member is in contact with the back surface of the silicon carbide substrate, thereby supporting the silicon carbide substrate;
A position regulating member that is disposed on the support member and regulates the position of the silicon carbide substrate in the surface direction of the silicon carbide substrate by interposing a gap with the outer periphery of the silicon carbide substrate;
A plate-like member that is disposed below the support member, supports the support member, and closes one end of the penetrating portion;
Only including,
The susceptor characterized in that the support member, the position regulating member, and the plate-like member are separate and separable . Said substrate containing member, said partitioned by the upper surface of the inner wall and the plate-like member of the support member, according to claim 5, characterized in that a recess which exposes the back surface of the silicon carbide substrate housed in the board housing member The described susceptor . 6. The susceptor according to claim 5, wherein each of the substrate housing member and the susceptor body is formed by coating a member made of carbon with a film made of silicon carbide. A susceptor cleaning method for removing a deposit made of silicon carbide deposited on a susceptor according to any one of claims 1 to 7 ,
Removing the susceptor to which the deposit has adhered from a film forming chamber of a silicon carbide film forming apparatus;
Placing the susceptor to which the deposit is attached in a chamber of a silicon carbide removing device, and disposing a susceptor protection substrate for protecting the susceptor in the housing portion of the substrate housing member;
An etching step of removing the deposit deposited on the susceptor by dry etching;
After the etching step, when the substrate housing member is damaged, an exchange step of replacing the damaged substrate housing member with another substrate housing member that is not damaged;
A method for cleaning a susceptor, comprising: The etching step supplies a plasma-containing fluorine-containing gas into the chamber to selectively remove a silicon component contained in the deposit;
A second step of selectively removing a carbon component contained in the deposit by supplying a plasma-containing oxygen-containing gas into the chamber;
Including
9. The susceptor cleaning method according to claim 8, wherein the first step and the second step are performed alternately or simultaneously. Examples susceptor protective substrate, according to claim 8 or 9 susceptor cleaning method wherein the use of silicon carbide substrate or a quartz substrate for the dummy.

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