JP2001114598A - Method of and device for producing silicon carbide single crystal - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for producing a silicon carbide single crystal by which the silicon carbide single crystal can be grow in a large length in a state flatly maintaining the growth surface of the single crystal without generating crack detects. SOLUTION: A graphite-made crucible 1 whose lid 11 comprises a seed crystal- adhering member 12 and a polycrystal growth member 13 surrounding the periphery of the projected portion 12a of the seed crystal-adhering member 12 is prepared. A seed crystal 3 is adhered to the surface 12b of the projected portion 12a, and silicon carbide raw material 2 is allowed to sublime, thus supplying the silicon carbide raw material gas to the growth surface of the seed crystal 3. Thereby, the silicon carbide single crystal 4 grows, and a polycrystal 6 simultaneously grows in the same height as the silicon carbide single crystal 4 on the surface 13c of the polycrystal growth member 13. When the silicon carbide single crystal 4 thus grows in such the state as embedded in the polycrystal 6, the temperature distribution of the growth surface of the silicon carbide single crystal 4 is approximately uniformed, and the silicon carbide single crystal can be grown in a long length in a state flatly maintaining the growth surface of the single crystal without generating crack detects.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a silicon carbide single crystal manufacturing method for manufacturing a high quality silicon carbide single crystal having few defects on a seed crystal with good yield, and a silicon carbide single crystal manufacturing apparatus suitable for the method.

[0002]

2. Description of the Related Art Silicon carbide single crystals are expected to be used as semiconductor substrates for power devices because of their characteristics of high breakdown voltage and high electron mobility. In a silicon carbide single crystal,
There is a demand for higher quality for higher yield and larger diameter and longer length for higher production. For the growth of silicon carbide single crystal, a single crystal growth method generally called a sublimation method (improved Rayleigh method) is used.

In the improved Rayleigh method, a silicon carbide raw material is inserted into a graphite crucible, and a seed crystal is mounted on the inner wall of the graphite crucible so as to face the raw material portion.
The substrate is heated to 0 to 2400 ° C. to generate a sublimation gas, and is recrystallized into a seed crystal whose temperature is lower by several tens to several hundreds degrees Celsius than a raw material part, thereby growing a silicon carbide single crystal.

[0004]

The present inventors prototyped a crucible made of graphite and manufactured a silicon carbide single crystal using a sublimation method. The situation at this time is shown in FIG. As shown in this figure, a projection 102a is provided on the inner wall of a lid 102 of a graphite crucible 101, and a seed crystal 103 is provided on the projection 102a.
Is to be pasted. Then, the protrusion 102a
A counterbore 102b is formed by recessing the opposite side of the surface on which the seed crystal 103 is attached, and a shielding plate 104 having a surface facing the growth surface of the seed crystal 103 is provided. Temperature is lower than that of the part. Using the graphite crucible 101 configured as described above, a silicon carbide single crystal 105 was grown on the seed crystal 103.

[0007] However, as shown in FIG. 7, when silicon carbide single crystal 105 is grown in crucible 101 made of graphite, silicon carbide single crystal 1
The growth surface of No. 05 became a curved surface, and there was a problem that a crack defect was generated on the curved surface.

The present invention has been made in view of the above-mentioned problems, and is directed to a method of manufacturing a silicon carbide single crystal which is grown long while keeping the growth surface of the silicon carbide single crystal flat, and which does not generate crack defects. It is an object of the present invention to provide a single crystal manufacturing apparatus.

[0007]

Means for Solving the Problems In order to solve the above problems, the present inventors have studied the cause of the growth surface of a silicon carbide single crystal being a curved surface.

First, thermal simulation analysis was performed when silicon carbide single crystal 105 was crystallized using graphite crucible 101 described above. FIG. 8 shows the temperature distribution in the graphite crucible 101 analyzed in this way. As shown in this figure, a temperature difference occurs between the center and the end of the growth surface of silicon carbide single crystal 105 by about 2 ° C., indicating that the isotherm is largely bent. Therefore, it is considered that the shape of the growth surface of silicon carbide single crystal 105 is determined according to the temperature distribution.

Therefore, in order to achieve the above object, according to the first aspect of the present invention, the seed crystal attaching portion (12a) and the peripheral portion (13) surrounding the seed crystal attaching portion are arranged on a predetermined surface. The crucible (1) provided is prepared, the seed crystal (3) is attached to the surface of the seed crystal sticking portion, and a silicon carbide raw material gas is introduced into the growth space in the crucible, and the seed crystal is placed on the growth surface of the seed crystal. While growing the silicon carbide single crystal (4), the polycrystal (6) was grown on the peripheral surface (13c) so as to have the same height as the silicon carbide single crystal, and was buried surrounded by the polycrystal. It is characterized in that a silicon carbide single crystal is grown in a state.

As described above, by growing a polycrystal having a height equivalent to that of a silicon carbide single crystal and growing the silicon carbide single crystal so as to be embedded in the polycrystal, the growth surface of the silicon carbide single crystal is grown. The temperature distribution can be made substantially uniform. For this reason, it is possible to lengthen the silicon carbide single crystal while keeping the growth surface flat, and to prevent generation of crack defects.

For example, as set forth in claim 2, a polycrystal having a growth surface substantially flat with the growth surface of the silicon carbide single crystal on the surface of the peripheral portion may be grown.

More specifically, the temperature of the growth surface of the seed crystal is set to be equal to or slightly lower than the temperature of the surface of the peripheral portion, thereby increasing the growth surface of the seed crystal. A silicon carbide single crystal can be grown thereon, and a polycrystal having the same height as the silicon carbide single crystal can be grown on the surface of the peripheral portion. For example, as shown in claim 4,
The thickness (A + B) of the peripheral portion may be larger than the thickness (C) of the silicon carbide attaching member.

According to a tenth aspect of the present invention, a thickness (B) of a portion constituting a surface on which a polycrystal grows in a peripheral portion is defined.
Is set to 5 mm or more, or by using a material having a lower thermal conductivity than other portions of the crucible, the temperature uniformity in the radial direction can be improved.

The invention according to claim 5 is characterized in that a predetermined gap is provided between the seed crystal attachment portion and an inner peripheral wall of the peripheral portion surrounding the seed crystal attachment portion.

Thereby, the silicon carbide single crystal formed on the growth surface of the seed crystal and the polycrystal formed on the peripheral surface can be separated. In this case, if the gap is too large, the gap becomes substantially equivalent to the growth space, and if it is too small, it becomes equivalent to no gap. Therefore, preferably, the gap is set to 1 mm. Good to do.

The invention according to claim 7 is characterized in that the seed crystal sticking portion and the peripheral portion are relatively reversely rotated.

Thus, the silicon carbide single crystal formed on the growth surface of the seed crystal and the polycrystal formed on the peripheral surface can be separated. In particular, when the silicon carbide single crystal or polycrystal becomes long, the grown crystals are easily integrated due to the lateral growth of each crystal, but such integration can be prevented.

[0018] In the invention according to claim 8, a silicon carbide raw material is provided on a surface of the crucible facing the predetermined surface on which the seed crystal attachment portion and the peripheral portion are disposed, and the seed is grown during growth of the silicon carbide single crystal. It is characterized in that the crystal sticking part is moved in a direction away from the silicon carbide raw material.

Thus, even when a silicon carbide single crystal or polycrystal is grown long, the silicon carbide single crystal can be separated from the silicon carbide raw material and controlled to a desired temperature state. For example, as set forth in claim 9, if the moving speed of the seed crystal attachment portion is made equal to the growth speed of the silicon carbide single crystal, the silicon carbide single crystal can be grown at a fixed position.
The temperature on the growth surface of the silicon carbide single crystal can be maintained at a constant temperature.

The invention according to claims 11 to 17 is an apparatus for producing a silicon carbide single crystal applied to the method for producing a silicon carbide single crystal according to claims 1 to 10.

Note that the reference numerals in parentheses of the above means indicate the correspondence with specific means described in the embodiments described later.

[0022]

DESCRIPTION OF THE PREFERRED EMBODIMENTS (First Embodiment) The embodiment shown in the drawings will be described below. FIG. 1 shows a graphite crucible 1 as a crystal growth apparatus used in the present embodiment. This figure shows the case where silicon carbide raw material 2 provided in graphite crucible 1 is sublimated by heat treatment, and silicon carbide single crystal 4 is grown on seed crystal 3 formed of a silicon carbide single crystal layer. 1 shows a cross-sectional configuration of a graphite crucible 1.

The graphite crucible 1 includes a crucible main body 10 having an open upper surface, and a lid member 11 for closing the opening of the crucible main body 10. A stepped portion 10 a is provided on the opening side of the crucible body 10.

Crucible body 10 has a cup shape having a circular cross section, and silicon carbide raw material 2 is provided at the bottom of the cup shape.

The lid 11 has a circular shape corresponding to the shape of the opening of the crucible body 10. The lid member 11 includes a seed crystal sticking member 12 and a polycrystalline growth member 13. The seed crystal sticking member 12 is formed by projecting a disc-shaped central portion into a columnar shape, and the seed crystal 3 can be stuck to a tip end surface 12b of the projecting portion (hereinafter referred to as a projecting portion) 12a. ing. Note that the protruding portion 12a shown here constitutes a seed crystal attaching portion, and a portion (a portion around the protruding portion 12a) 12c of the seed crystal attaching member 12 other than the protruding portion 12a and the polycrystalline growth member 13 are peripheral portions. Unit.

The polycrystalline growth member 13 is inserted through the opening of the crucible main body 10 and is held at a predetermined position near the opening by a stepped portion 10a formed in the crucible main body 10.

The polycrystalline growth member 13 has a cavity 13a having a circular cross section at the center.
The protruding portion 12a of the seed crystal attaching member 12 is inserted into a, so that the outer peripheral wall of the protruding portion 12a is surrounded by the inner wall surface of the cavity 13a. Cavity 13a of polycrystalline growth member 13
Is slightly larger than the outer diameter of the protruding portion 12a of the seed crystal affixing member 12, so that the gap d between the inner peripheral wall of the cavity 13a and the outer peripheral wall of the protruding portion 12a has a predetermined interval. I have. Specifically, the size of the gap d is set to be about 1 mm. This is because if the gap d is too small, it is substantially the same as when no gap is provided, and if it is too large, it acts similarly to the growth space in the graphite crucible 1. It is. Also,
The polycrystal manufacturing member 13 is provided with a cylindrical guide 13b formed so as to be spaced apart from the cavity 13a at equal intervals and to surround the cavity 13a. Guide 13b extends from surface 13c of polycrystalline growth member 13 parallel or coplanar with the growth surface of tip end surface 12b of protrusion 12a toward silicon carbide raw material 2.

FIG. 2 is an enlarged view of the vicinity of the lid member 11 of the graphite crucible 1. As shown in the figure, the thickness of a portion 12c around the protruding portion 12a of the seed crystal attaching member 12 is set to A, and the protruding portion 12a of the polycrystalline growth member 13 is set.
(The guide 1 of the polycrystalline growth member 13)
Assuming that the thickness of the portion (the portion inside 3b) is B and the thickness of the protruding portion 12a of the seed crystal attaching member 12 is C, the sum of the thickness A and the thickness B is larger than the thickness C (A + B> C). I have to.

When the seed crystal 3 is attached, the thicknesses A to C are set so that the growth surface of the seed crystal 3 is substantially flat with respect to the surface 13c of the polycrystalline growth member 13 or slightly protrudes. Is set.

With this structure, when seed crystal attaching member 12 and polycrystalline growth member 13 are viewed from silicon carbide raw material 2 side, and when seed crystal 3 is not attached, projecting portion 12a is formed by polycrystalline growth. When the seed crystal 3 is attached, the growth surface of the seed crystal 3 is flat with respect to the surface of the polycrystal growth member 13 or slightly protrudes from the surface of the polycrystal growth member 13 when the seed crystal 3 is attached. .

Further, as shown in FIG. 1, the graphite crucible 1 can be heated by a heater 5 in a vacuum vessel (heating furnace) into which an argon gas can be introduced. Thereby, the temperature of seed crystal 3 is maintained at a temperature lower by about 100 ° C. than the temperature of silicon carbide raw material 2.

The temperature distribution when the graphite crucible 1 thus configured was heated by the heater 5 was determined by thermal simulation. The result is shown in FIG. The dotted line shown in this figure represents an isotherm, and the temperature increases in order from the upper side to the lower side of the paper. As shown in this figure, the surface temperature of seed crystal 3 is slightly lower than the temperature of the surface of polycrystalline growth member 13. Then, the growth surface temperatures of seed crystal 3 and silicon carbide single crystal 4 are substantially uniform. Specifically, the temperature distribution ΔT is 0.3
° C.

This is because the protruding portion 12a to which the seed crystal 3 is attached is cut off from the polycrystalline growth member 13, and the thickness C of the protruding portion 12a is smaller than the sum of the thickness A and the thickness B of the surrounding portion. Therefore, due to heat conduction, the polycrystalline growth member 13
This is because the heat is hardly transmitted, and the protruding portion 12a is configured to easily radiate heat to the outside.

Using the graphite crucible 1 thus configured, a silicon carbide single crystal 4 was grown on a seed crystal 3 having a (0001) plane as a growth surface. Specifically, the growth was performed for 15 hours while the growth pressure was set to 100 Torr and the growth rate was controlled by reducing the transport speed of the raw material. Thereby, as shown in FIG. 1, polycrystal 6 similarly grew on surface 13 c of polycrystal growth member 13 along with growth of silicon carbide single crystal 4. At this time, it was found that polycrystal 6 grew so as to surround silicon carbide single crystal 4 at a predetermined distance from silicon carbide single crystal 4. In other words, buried growth is performed in which silicon carbide single crystal 4 grows in a state of being buried in polycrystal 6.

The growth surface of silicon carbide single crystal 4 is substantially flat or slightly protruded from the growth surface of polycrystal 6. Grew with the positional relationship with the height of the growth surface kept almost constant. This is silicon carbide single crystal 4
This shows that even when the polycrystal 6 is grown, the temperature relationship between the respective growth surfaces is similar to the temperature relationship between the growth surface of the seed crystal 3 and the surface of the polycrystal growth member 13 described above. That is, the temperature on the growth surface of silicon carbide single crystal 4 is slightly lower than the temperature on the growth surface of polycrystal 6, and the temperature distribution on the growth surface of silicon carbide single crystal 4 becomes uniform.

Further, in silicon carbide single crystal 4, a facet surface extending in a ripple shape from substantially the center of the growth surface was formed. This facet surface occupies 60% or more of the growth surface of silicon carbide single crystal 4, and no crack defect has occurred in the portion serving as the facet surface.

As described above, the silicon carbide single crystal 4 and the polycrystal 6 are placed on adjacent growth surfaces having substantially the same height (in this embodiment, the growth surface of the seed crystal 3 and the growth surface of the polycrystal growth member 1).
When the silicon carbide single crystal 4 and the polycrystal 6 are grown on the surface 13c) of the third crystal 3, they can be grown together at a predetermined interval. Since the temperature distribution on the growth surface of seed crystal 3 and the growth surface of silicon carbide single crystal 4 can be made substantially uniform, the growth surface of silicon carbide single crystal 4 can be made flat, and Crack defects in silicon carbide single crystal 4 can be eliminated.

Further, since the growth surface of silicon carbide single crystal 4 can be made flat, the number of wafers can be increased when the wafer is cut out, and even in the doping technique, the incorporation of impurities can be made uniform. can do. (Second Embodiment) FIG. 4 shows a cross-sectional configuration of a graphite crucible 1 used as a second embodiment of the present invention. Since the graphite crucible 1 of the present embodiment has substantially the same configuration as the graphite crucible 1 used in the first embodiment, the same reference numerals are given to the same components as those in FIG. explain.

As shown in FIG. 4, the crucible body 10 of the graphite crucible 1 is located above the portion where the seed crystal sticking member 12 and the polycrystalline growth member 13 are arranged (the silicon carbide raw material 2 is arranged). (In a direction away from the side where it is located), so that the seed crystal sticking member 12 and the polycrystalline growth member 13 are pulled upward. The seed crystal sticking member 12 and the polycrystal growth member 13
Are connected at a portion where they are in contact with each other, and are configured to be pulled up by a support member 14 provided on the seed crystal attaching member 12.

Using the graphite crucible 1 configured as described above, the silicon carbide single crystal 4 is grown on the growth surface of the seed crystal 3 and the surface of the polycrystal growth member 13 as in the first embodiment. Polycrystalline 6 was grown on 13c. At this time, the growth rate is made equal to the growth rate of silicon carbide single crystal 4.
Seed crystal sticking member 12 and polycrystalline growth member 13 were pulled upward so that the distance from the growth surface of silicon carbide single crystal 4 and the growth surface of polycrystal 6 to silicon carbide raw material 2 was constant. Specifically, the pulling speed of the seed crystal sticking member 12 and the polycrystalline growth member 13 was set to 0.2 to mm / h.

As described above, by making the distance from the growth surface of silicon carbide single crystal 4 and the growth surface of polycrystal 6 to silicon carbide raw material 2 constant, the growth of silicon carbide single crystal 4 can be improved. In addition, the temperature of the growth surface of silicon carbide single crystal 4 and the growth surface of polycrystal 6 can be prevented from changing much with time. Therefore, the crystallinity of silicon carbide single crystal 4 can be further improved.

(Third Embodiment) FIG. 5 shows a cross-sectional structure of a graphite crucible 1 used as a third embodiment of the present invention.
Since the graphite crucible 1 of the present embodiment has substantially the same configuration as the graphite crucible 1 used in the first embodiment, the same reference numerals are given to the same components as those in FIG. explain.

As shown in FIG. 5, the seed crystal sticking member 12
Are arranged in a cavity 13 a formed in the polycrystalline growth member 13. The seed crystal sticking member 12 and the polycrystalline growth member 13 are supported by support members 15 and 16, respectively.
It is configured to rotate in opposite directions about 5, 16 as a central axis. However, the support member 16 has a cylindrical shape, and the center thereof coincides with the center of the support member 15. In this embodiment, the seed crystal sticking member 12 forms a seed crystal sticking portion, and the polycrystalline growth member 13 forms a peripheral portion.

Using the graphite crucible 1 configured as described above, the silicon carbide single crystal 4 is grown on the growth surface of the seed crystal 3 and the surface of the polycrystal growth member 13 in the same manner as in the first embodiment. Polycrystalline 6 was grown on 13c. At this time, the seed crystal sticking member 12 and the polycrystal growth member 13 were rotated in opposite directions.

As described above, silicon carbide single crystal 4 and polycrystal 6
By rotating seed crystal applying member 12 and polycrystalline growth member 13 in directions opposite to each other with the growth of silicon carbide single crystal 4 and polycrystal 6, even if growth proceeds, they can be reliably separated. Can be prevented from adhering. That is, the growth amount of silicon carbide single crystal 4 and polycrystal 6 is almost constant, so that the growth surface is kept flat. There is a possibility that the temperature difference between the two will disappear and the two will be integrated. Therefore, by rotating seed crystal attaching member 12 and polycrystalline growth member 13 in opposite directions, silicon carbide single crystal 4 and polycrystal 6 can be prevented from being integrated, and a long silicon carbide single crystal can be prevented. 4 can be formed with good crystallinity.

(Fourth Embodiment) FIG. 6 shows a sectional configuration of a graphite crucible 1 used as a fourth embodiment of the present invention.
Since the graphite crucible 1 of the present embodiment has substantially the same configuration as the graphite crucible used in the third embodiment, FIG.
The same reference numerals are given to the same configurations as those described above, and only different portions will be described.

As shown in FIG. 6, the graphite crucible 1 of the present embodiment has a crucible body 10 extending upward from the graphite crucible 1 of the third embodiment shown in FIG. The difference is that it has a different configuration. Thereby, the seed crystal sticking member 12 and the polycrystalline growth member 13 are configured to be pulled upward. That is, in the present embodiment, the seed crystal sticking member 12 and the polycrystalline growth member 13 are configured to be able to rotate in opposite directions to each other, as in the third embodiment, and the seed crystal is rotated in the The bonding member 12 and the polycrystalline growth member 13 are configured to be lifted.

Using the graphite crucible 1 thus configured, a silicon carbide single crystal 4 is grown on the growth surface of the seed crystal 3 in the same manner as in the first embodiment, and the surface of the polycrystal growth member 13 is formed. A polycrystal 6 was grown. At this time, seed crystal attaching member 12 and polycrystalline growing member 13 are rotated in opposite directions to each other, and seed crystal attaching member 12 and polycrystalline growing member 13 are rotated at the same speed as silicon carbide single crystal 4 and polycrystalline growth. And lifted up.

As described above, by rotating seed crystal applying member 12 and polycrystalline growth member 13 in opposite directions, silicon carbide single crystal 4 and polycrystal 6 can be reliably separated.
Further, by pulling up seed crystal attaching member 12 and polycrystalline growth member 13 in the upward direction, the temperature of the growth surface of silicon carbide single crystal 4 and the growth surface of polycrystal 6 can be prevented from changing with time. Therefore, the crystallinity of silicon carbide single crystal 4 can be further improved, and silicon carbide single crystal 4 can be made longer.

(Other Embodiments) In the first to fourth embodiments, the thickness C of the projecting portion 12a of the seed crystal attaching member 12
According to the relationship between the thickness A and the thickness B around the periphery,
Although the temperature of the growth surface of seed crystal 3 and silicon carbide single crystal 4 is lower than the growth surface of polycrystal 6, the temperature relationship may be established by another configuration.

In the third and fourth embodiments, the seed crystal sticking member 12 and the polycrystalline growth member 13 are rotated in directions opposite to each other.
It is not necessary to rotate both. For example, only the seed crystal attaching member 12 may be rotated. Further, the crucible body 10 may be rotated in addition to the seed crystal attaching member 12 and the polycrystalline growth member 13. In this case, the crucible body 10 is rotated in a direction opposite to that of the polycrystalline growth member 13.

In the second and fourth embodiments, the seed crystal sticking member 12 and the polycrystalline growth member 13 are both pulled up. However, only the seed crystal sticking member 12 is pulled up. Is also good. In this case, the growth surface of polycrystal 6 may be located lower than the growth surface of silicon carbide single crystal 4. However, since the temperature of silicon carbide single crystal 4 is lower than that of polycrystal 6, silicon carbide single crystal Only 4 grows and the growth surface remains almost flat. The periphery of the growth surface of silicon carbide single crystal 4 is Si /
Since growth proceeds in a state surrounded by polycrystal 6 having a stable C ratio, silicon carbide single crystal 4 can be formed with good crystallinity. In addition, silicon carbide single crystal 4
And the growth surface of the polycrystal 6 can be automatically corrected by sublimation and recrystallization of the polycrystal 6.

[Brief description of the drawings]

FIG. 1 is a graphite crucible 1 according to a first embodiment of the present invention.
FIG. 3 is a diagram showing a cross-sectional configuration of FIG.

FIG. 2 is a view for explaining the thickness of each part of a lid material 11 of the graphite crucible 1 shown in FIG.

FIG. 3 is a diagram showing a result obtained by simulation of a temperature portion on a growth surface of a seed crystal 3 when the graphite crucible 1 shown in FIG. 1 is used.

FIG. 4 is a graphite crucible 1 according to a second embodiment of the present invention.
FIG. 3 is a diagram showing a cross-sectional configuration of FIG.

FIG. 5 is a graphite crucible 1 according to a third embodiment of the present invention.
FIG. 3 is a diagram showing a cross-sectional configuration of FIG.

FIG. 6 is a graphite crucible 1 according to a fourth embodiment of the present invention.
FIG. 3 is a diagram showing a cross-sectional configuration of FIG.

FIG. 7 is a diagram showing a cross-sectional configuration of a graphite crucible 101 prototyped by the present inventors.

8 is a diagram showing a result obtained by simulation of a growth surface tail temperature distribution of a seed crystal 103 in a case where the graphite crucible 101 shown in FIG. 7 is used.

[Explanation of symbols]

1 ... graphite crucible, 2 ... silicon carbide raw material, 3 ... seed crystal, 4
... silicon carbide single crystal, 6 ... polycrystal, 10 ... crucible body, 1
DESCRIPTION OF SYMBOLS 1 ... Lid material, 12 ... Seed crystal sticking member, 12a ... Projection part, 1
2b: tip surface, 13: polycrystalline growth member, 13a: cavity, 13b: guide, 13c: surface, 14-16: support member, d: gap.

 ────────────────────────────────────────────────── ─── Continuing from the front page (72) Inventor Yuki Futyama 1-1-1, Showa-cho, Kariya-shi, Aichi Prefecture Inside DENSO Corporation (72) Inventor Shoichi Onda 1-1-1, Showa-cho, Kariya-shi, Aichi Co., Ltd. Inside DENSO (72) Inventor Tomisao Hirose 1-1-1, Showa-cho, Kariya, Aichi Prefecture Inside Denso Corporation (72) Inventor Hidemi Oguri 1-1-1, Showa-cho, Kariya City, Aichi Prefecture Inside DENSO Corporation (72) Inventor Naohiro Sugiyama 41-cho, Yokomichi, Nagakute-cho, Aichi-gun, Aichi Prefecture F-term in Toyota Central R & D Laboratories, Inc. (reference) 4G077 AA02 BE08 DA02 ED01 EG02 EG11 EG20 EG25 HA12

Claims (17)

[Claims] 1. A crucible (1) having a seed crystal sticking portion (12a) and peripheral portions (12c, 13) surrounding the seed crystal sticking portion arranged on a predetermined surface is prepared. Attaching a seed crystal (3) to the surface (12b) of the attaching section; introducing a silicon carbide source gas into a growth space in the crucible;
A silicon carbide single crystal (4) is grown on the growth surface of the seed crystal, and a polycrystal (6) is grown on the peripheral surface (13c) so as to have the same height as the silicon carbide single crystal. Growing the silicon carbide single crystal in a state of being buried surrounded by the polycrystal. 2. A crucible (1) having a seed crystal sticking portion (12a) and peripheral portions (12c, 13) surrounding the seed crystal sticking portion arranged on a predetermined surface is prepared. Attaching a seed crystal (3) to the surface (12b) of the attaching section; introducing a silicon carbide source gas into a growth space in the crucible;
Growing a silicon carbide single crystal on the growth surface of the seed crystal and growing a polycrystal (6) having a growth surface substantially flat with the growth surface of the silicon carbide single crystal on the surface of the peripheral portion. A method for producing a silicon carbide single crystal, which is characterized by the following. 3. A crucible (1) having a seed crystal sticking part (12a) and a peripheral part (12c, 13) surrounding the seed crystal sticking part disposed on a predetermined surface is prepared. Attaching a seed crystal (3) to the surface (12b) of the attaching section; introducing a silicon carbide source gas into a growth space in the crucible;
The silicon carbide single crystal (4) is grown on the seed crystal growth surface such that the temperature of the seed crystal growth surface is lower than the temperature of the peripheral edge surface (13c). A method for producing a silicon carbide single crystal, comprising growing a polycrystal (6) having a height equal to that of the silicon carbide single crystal on the surface of the portion. 4. A crucible (1) having a seed crystal sticking part (12a) and a peripheral part (12c, 13) surrounding the seed crystal sticking part arranged on a predetermined surface is prepared. Attaching a seed crystal (3) to the surface (12b) of the attaching section; introducing a silicon carbide source gas into a growth space in the crucible;
The thickness (A + B) of the peripheral portion is made larger than the thickness of the seed crystal attaching portion, and a silicon carbide single crystal (4) is grown on the growth surface of the seed crystal, and the surface (13c) of the peripheral portion is formed. A) growing a polycrystal (6) having the same height as the silicon carbide single crystal. 5. A predetermined gap is provided between the seed crystal sticking portion and an inner peripheral wall of the peripheral portion surrounding the seed crystal sticking portion.
5. A method for producing a silicon carbide single crystal according to any one of the above. 6. The method for producing a silicon carbide single crystal according to claim 5, wherein the gap is set to 0.5 to 3 mm. 7. The method for producing a silicon carbide single crystal according to claim 1, wherein the seed crystal attachment portion and the peripheral portion are relatively reversely rotated. 8. A silicon carbide raw material (2) is provided on a surface of the crucible opposite to the predetermined surface on which the seed crystal attachment portion and the peripheral portion are provided, and the silicon carbide single crystal is grown during growth. The method for producing a silicon carbide single crystal according to any one of claims 1 to 7, wherein the seed crystal attaching section is moved in a direction away from the silicon carbide raw material. 9. The method for producing a silicon carbide single crystal according to claim 8, wherein a moving speed of the seed crystal attaching portion is made equal to a growth speed of the silicon carbide single crystal. 10. A thickness (B) of a member (13) constituting a surface on which the polycrystal grows in the peripheral portion is set to 5%.
The method for producing a silicon carbide single crystal according to any one of claims 1 to 6, wherein the thickness is not less than mm. 11. A crucible (1) having a seed crystal sticking part (12a) and a peripheral part (12c, 13) surrounding the seed crystal sticking part disposed on a predetermined surface, wherein the seed crystal is provided. By attaching the seed crystal (3) to the surface of the attaching portion and introducing a silicon carbide source gas into the growth space in the crucible,
A silicon carbide single crystal (4) is grown on the growth surface of the seed crystal. The silicon carbide single crystal is grown on the growth surface of the seed crystal, and the silicon carbide single crystal is grown on the peripheral surface (13c). It is configured to grow a polycrystal (6) so as to have a height equivalent to that of the silicon carbide single crystal, and to grow the silicon carbide single crystal in a state of being buried surrounded by the polycrystal. An apparatus for producing a silicon carbide single crystal. 12. A crucible (1) having a seed crystal sticking part (12a) and a peripheral part (12c, 13) surrounding the seed crystal sticking part arranged on a predetermined surface, wherein the seed crystal is provided. By attaching the seed crystal (3) to the surface of the attaching portion and introducing a silicon carbide source gas into the growth space in the crucible,
A silicon carbide single crystal (4) is grown on the growth surface of the seed crystal, and the seed crystal sticking portion and the peripheral portion have a growth surface temperature of the seed crystal attached to the seed crystal sticking portion. Is configured to be lower than the surface temperature of the peripheral portion. 13. A crucible (1) having a seed crystal sticking portion (12a) and a peripheral portion (12c, 13) surrounding the seed crystal sticking portion disposed on a predetermined surface, wherein the seed crystal is provided. By attaching the seed crystal (3) to the surface of the attaching portion and introducing a silicon carbide source gas into the growth space in the crucible,
A silicon carbide single crystal (4) is grown on the growth surface of the seed crystal, and in the growth direction of the silicon carbide single crystal, the thickness (C) of the seed crystal attachment portion is equal to the thickness of the peripheral portion. An apparatus for producing a silicon carbide single crystal, wherein the apparatus is thinner than (A + B). 14. A predetermined gap is provided between the seed crystal sticking portion and an inner peripheral wall of the peripheral portion surrounding the seed crystal sticking portion.
3. The apparatus for producing a silicon carbide single crystal according to any one of 3. 15. The apparatus according to claim 14, wherein the gap is set to 0.5 to 3 mm. 16. The method according to claim 16, wherein the seed crystal attachment portion and the peripheral portion are
The apparatus for producing a silicon carbide single crystal according to any one of claims 11 to 15, wherein the apparatus is configured to be relatively rotated in the reverse direction. 17. A structure in which a silicon carbide raw material (2) is provided on a surface of the crucible facing the predetermined surface on which the seed crystal attaching portion and the peripheral portion are provided, and wherein the seed crystal is provided. The apparatus for producing a silicon carbide single crystal according to any one of claims 11 to 16, wherein an attaching part is moved in a direction away from the silicon carbide raw material.