JP2017088415A - SiC SINGLE CRYSTAL GROWTH APPARATUS, AND SiC SINGLE CRYSTAL GROWING METHOD - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a SiC single crystal growth apparatus and a SiC single crystal growing method capable of forming a long-sized, large bore and high quality SiC single crystal.SOLUTION: A SiC single crystal growth apparatus 100 comprises: a crucible 10 capable of housing a SiC single crystal growing material 11 therein; a lid 20 including a ceiling part 20A having a seed crystal installation part 21 at a position to confront the crucible 10, and a side wall 20B enclosing the crucible 10 thereby to cover the crucible 10; a guide member 30 having a guide part 30A extending from the side of the seed crystal installation part 21 toward the side of the crucible 10 and a support part 30B supporting the guide part 30A; and rotation driving means 40 for rotating the seed crystal installation part 21 and/or the guide member 30.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a SiC single crystal growth apparatus and a SiC single crystal growth method.

  Silicon carbide (SiC) has a dielectric breakdown electric field one order of magnitude larger than silicon (Si) and a band gap three times larger. Silicon carbide (SiC) has characteristics such as about three times higher thermal conductivity than silicon (Si). Therefore, silicon carbide (SiC) is expected to be applied to power devices, high frequency devices, high temperature operation devices, and the like. For this reason, in recent years, SiC epitaxial wafers have been used for the above semiconductor devices.

  A SiC epitaxial wafer is manufactured by growing a SiC epitaxial film which becomes an active region of a SiC semiconductor device by a chemical vapor deposition (CVD) method on a SiC single crystal substrate.

  The SiC single crystal substrate is produced by cutting out a SiC single crystal. This SiC single crystal can generally be obtained by a sublimation method. In the sublimation method, a seed crystal made of SiC single crystal is placed on a pedestal placed in a graphite crucible, and the sublimation gas sublimated from the raw material powder in the crucible is supplied to the seed crystal by heating the crucible. Is grown into a larger SiC single crystal.

  In recent years, with the demand of the market, it is required to increase the diameter of a SiC single crystal substrate on which a SiC epitaxial film is grown. For this reason, the demand for increasing the diameter and length of the SiC single crystal itself is increasing. For example, Patent Document 1 describes a single crystal growth apparatus provided with a tapered guide member for expanding the diameter of a SiC single crystal.

Moreover, the request | requirement of quality improvement is also increasing with the request | requirement of large diameter and lengthening of a SiC single crystal. In the crystal growth of a SiC single crystal, there are various factors that affect its quality.
For example, the temperature condition at the time of crystal growth of a SiC single crystal greatly affects the quality of the SiC single crystal. Therefore, Patent Document 2 describes a single crystal growth apparatus in which the positions of the seed crystal and the crucible are moved up and down and rotated in order to make the temperature of the crystal growth surface of the SiC single crystal uniform.

  In addition, when a single crystal grown from a seed crystal and a polycrystalline crystal grown in other portions are in contact with each other, defects, heterogeneous polymorphism, and cracks are caused, and the quality of the SiC single crystal is deteriorated. Therefore, for example, Patent Document 3 describes a method for producing a single crystal while keeping a tapered guide member at a high temperature. By keeping the guide member at a high temperature, the crystal growth of polycrystalline SiC on the surface of the guide member is suppressed.

JP 2002-60297 A JP-A-6-298594 JP2013-166672A

  However, the methods described in Patent Documents 1 to 3 cannot form a SiC single crystal that is sufficiently long, large in diameter, and high in quality.

  For example, in a single crystal crystal apparatus provided with a tapered guide member described in Patent Document 1, polycrystals grow on the surface of the guide member. This polycrystal may be integrated with the single crystal grown from the seed crystal during the growth process. If the polycrystal and the single crystal are integrated, defects, heterogeneous polymorphs, cracks, and the like may occur near the interface, and a high-quality SiC single crystal cannot be obtained.

  The single crystal growth method described in Patent Document 3 is intended to solve this problem. However, even if the guide member is at a high temperature, it is not possible to completely suppress the crystal growth of polycrystals on the guide. Therefore, a sufficiently high quality SiC single crystal cannot be obtained.

  The single crystal growth apparatus described in Patent Document 2 can keep the temperature of the crystal growth surface constant. However, since there is no guide member, it is impossible to realize a long and large aperture. In addition, since there is no guide member, the source gas supplied to portions other than the seed crystal grows as crystals at those locations. These polycrystals may be integrated with a single crystal grown from a seed crystal and deteriorate the quality of the crystal. The source gas supplied to the portion other than the seed crystal flows out from the gap in the vertical direction of the apparatus. If the outflow amount of the source gas increases, efficient crystal growth cannot be performed. Furthermore, the source gas supplied to the portion other than the seed crystal may grow in a gap near the drive surface that moves the support portion where the seed crystal is installed up and down and rotate, and may clog the gap. In this case, up and down and rotation cannot be performed. That is, a sufficiently high quality SiC single crystal cannot be obtained.

  For this reason, a SiC single crystal growth apparatus and a SiC single crystal growth method capable of forming a long, large-diameter, and high-quality SiC single crystal have been eagerly demanded.

  The present invention has been made in view of the above problems, and provides a SiC single crystal growth apparatus and a SiC single crystal growth method capable of forming a long, large diameter, and high quality SiC single crystal. Objective.

As a result of intensive studies, the present inventors have found that it takes a certain amount of time to integrate the single crystal grown from the seed crystal and the polycrystal formed on the guide member. Therefore, by performing crystal growth in a state where the guide member is constantly moving relative to the single crystal, the single crystal and the polycrystal are not integrated, and are long, large-diameter, and high-quality SiC. The present inventors have found that a single crystal can be formed and completed the present invention.
That is, this invention provides the following means in order to solve the said subject.

(1) An SiC single crystal growth apparatus according to an aspect of the present invention includes a crucible that can accommodate an SiC single crystal growth raw material therein, a ceiling portion having a seed crystal installation portion at a position facing the crucible, and the crucible. A guide member having a side wall surrounding the crucible, a guide member extending from the seed crystal installation part side toward the crucible side, and a support part supporting the guide part; Rotation drive means for rotating the seed crystal installation part and / or the guide member.

(2) In the SiC single crystal growth apparatus according to (1), the guide member and the crucible may be integrated.

(3) In the SiC single crystal growth apparatus according to either (1) or (2) above, the shortest distance between the outer wall of the crucible and the side wall of the lid may be more than 0.01 mm and not more than 10 mm. .

(4) In the SiC single crystal growth apparatus according to any one of (1) to (3), the surface of the guide member may be coated with tantalum carbide.

(5) An SiC single crystal growth method according to an aspect of the present invention includes a step of storing a raw material for SiC single crystal growth in a crucible, a step of disposing a guide member on the open end side of the crucible, and a lid body And a step of covering the crucible and the guide member with a lid on which the seed crystal is placed so that the seed crystal faces the raw material for SiC single crystal growth. And a step of sublimating the SiC single crystal growth raw material while relatively rotating the seed crystal and the guide member.

(6) In the SiC single crystal growth method according to (5) above, a rotation speed of the guide member with respect to the seed crystal may be 0.1 rpm to 30 rpm.

  The SiC single crystal growth apparatus according to an aspect of the present invention includes a rotation drive unit that rotates the seed crystal installation unit and / or the guide member. Therefore, the seed crystal installed in the seed crystal installation part and the guide member can be operated relatively. Therefore, it is possible to inhibit the polycrystal grown on the guide member and the single crystal grown from the seed crystal from being integrated. Therefore, a long, large diameter and high quality SiC single crystal can be formed.

  The lid body covers the crucible. Therefore, a part of the raw material gas generated from the raw material for SiC single crystal stored in the crucible flows along the lid and flows out from below the SiC single crystal growth apparatus. Since the source gas flows from a high temperature toward a low temperature, the outflow of the source gas can be suppressed and efficient crystal growth can be performed. Moreover, since the temperature below the SiC single crystal growth apparatus is high to heat the crucible, it is possible to suppress recrystallization of the source gas in the vicinity thereof. Therefore, it is possible to suppress the source gas from being recrystallized, filling the gap in the drive region, and hindering the rotational drive.

  In the SiC single crystal growth apparatus according to one aspect of the present invention, the crucible and the guide member may be integrated. By integrating the crucible and the guide member, the amount of members used in the apparatus can be reduced, and the cost of the apparatus can be reduced. Further, in the growth of the SiC single crystal, it is preferable to reduce the amount of the source gas flowing out to the outside and perform the crystal growth efficiently. By reducing the amount of members used in the apparatus, the flow path through which the source gas flows can be narrowed.

  In the SiC single crystal growth apparatus according to one aspect of the present invention, the shortest distance between the guide member and the side wall of the lid may be more than 0.01 mm and not more than 10 mm. By securing the distance between the guide member and the side wall of the lid with a certain width, it is possible to suppress the source gas from being recrystallized during this period and hindering rotational driving. Further, by narrowing the distance between the guide member and the inner wall of the lid as much as possible, the amount of source gas flowing out can be reduced, and crystal growth can be performed efficiently.

  In the SiC single crystal growth apparatus according to one aspect of the present invention, the surface of the guide member may be coated with tantalum carbide. During the SiC crystal growth, the inside of the SiC single crystal growth apparatus becomes a high temperature of about 2000 ° C. to 2550 ° C. Tantalum carbide can withstand high temperatures and does not cause unnecessary reactions with the source gas. Therefore, high-quality SiC single crystal growth can be performed stably.

  In the SiC single crystal growth method according to an aspect of the present invention, the SiC single crystal growth raw material is sublimated while the seed crystal and the guide member are relatively rotated. Therefore, a high-quality SiC single crystal can be grown on the seed crystal without integrating the polycrystal grown on the guide member and the single crystal grown from the seed crystal. Moreover, a long and large-diameter SiC single crystal can be obtained by the guide member.

  In the SiC single crystal growth method according to one aspect of the present invention, the rotational speed of the guide member relative to the seed crystal may be 0.1 rpm to 30 rpm. By setting the relative rotation speed within the range, it is possible to inhibit the polycrystal and the SiC single crystal from being integrated efficiently and at low cost.

It is a cross-sectional schematic diagram of the SiC single crystal growth apparatus which concerns on 1st Embodiment of this invention. It is the cross-sectional schematic diagram which expanded the seed crystal installation part vicinity of the SiC single crystal growth apparatus which concerns on 1 aspect of this invention. It is a figure for demonstrating the function of the SiC single crystal growth apparatus which concerns on 1 aspect of this invention, and is the cross-sectional schematic diagram which expanded the part relevant to the flow of source gas. It is a cross-sectional schematic diagram of the SiC single crystal growth apparatus which does not have a guide member. It is a cross-sectional schematic diagram of the SiC single crystal growth apparatus which is not rotationally driven. It is a cross-sectional schematic diagram of the SiC single crystal growth apparatus which concerns on 2nd Embodiment of this invention. It is a cross-sectional schematic diagram which shows the other example of the crucible with a guide of the SiC single crystal growth apparatus which concerns on 2nd Embodiment of this invention.

Hereinafter, a SiC single crystal growth apparatus and a SiC single crystal growth method to which the present invention is applied will be described in detail with reference to the drawings as appropriate.
In the drawings used in the following description, in order to make the characteristics of the present invention easier to understand, the characteristic parts may be shown in an enlarged manner for the sake of convenience, and the dimensional ratios of the respective components are different from actual ones. Sometimes. In addition, the materials, dimensions, and the like exemplified in the following description are examples, and the present invention is not limited to these, and can be appropriately modified and implemented without changing the gist thereof.

(SiC single crystal growth apparatus, SiC single crystal growth method)
[First Embodiment]
FIG. 1 is a schematic cross-sectional view of an SiC single crystal growth apparatus according to a first embodiment of the present invention.
The SiC single crystal growth apparatus 100 includes a crucible 10, a lid 20, a guide member 30, and a rotation driving means 40. On the outer periphery of the lid body 20, there may be provided a heating means 50 and a heat insulating material 60 for keeping the heated crucible 10 warm. In FIG. 1, the SiC single crystal growth raw material 11, the seed crystal 22, and the SiC single crystal 23 grown from the seed crystal 22 are shown together to help understanding. The SiC single crystal growth raw material 11 is accommodated in the crucible 10. The seed crystal 22 is provided in a seed crystal installation portion 21 provided in the lid body 20.
In the drawings, the direction in which the seed crystal mounting portion 21 and the SiC single crystal growth raw material 11 are opposed to each other is defined as the vertical direction, and the direction perpendicular to the vertical direction is defined as the horizontal direction.

  As the crucible 10, a known material can be used as long as it is a crucible for producing a SiC single crystal by a sublimation method. For example, graphite, tantalum carbide, or the like can be used. The crucible 10 becomes high temperature during growth. Therefore, it must be formed of a material that can withstand high temperatures. For example, graphite has an extremely high sublimation temperature of 3550 ° C. and can withstand high temperatures during growth.

  A support member 12 that holds the crucible 10 may be provided below the crucible 10. For example, the support member 12 can be operated in the vertical direction, so that the crucible 10 can be easily put in and out of the region heated by the heating member 50.

  The lid 20 has a ceiling 20A and a side wall 20B surrounding the crucible 10. The lid 20 has a larger diameter than the crucible 10 and covers the crucible 10 with the ceiling 20A and the side wall 20B of the lid 20. The lower surface of the lid 20 may be released.

  A reaction space K in which the crystal growth of the SiC single crystal 23 proceeds is formed by the crucible 10 and the lid 20. Essentially, the reaction space K is preferably a closed space in order to suppress waste of the source gas. In the present embodiment, there is a gap between the crucible 10 and the lid 20 in order to rotationally drive a guide member described later.

  The seed crystal installation unit 21 covers the crucible 10 with the lid 20 so as to face the SiC single crystal growth raw material 11 housed in the crucible 10. The SiC single crystal growth raw material 11 and the seed crystal 22 installed in the seed crystal installation unit 21 face each other, whereby an efficient source gas can be supplied to the seed crystal 22.

  The seed crystal installation part 21 is preferably provided at the center of the lid 20 in the left-right direction. By providing the seed crystal installation portion 21 at the center of the lid 20 in the left-right direction, the growth rate of the SiC single crystal 23 can be made constant in the left-right direction. As will be described later, in the SiC single crystal growth apparatus 100 of the present embodiment, since the lid 20 may rotate, the seed crystal installation portion 21 is arranged in the horizontal direction of the lid 20 in order to minimize the influence of rotation. It is preferable to provide in the center.

  The lid 20 and the seed crystal installation part 21 are not particularly limited as long as they can withstand high temperatures, and the same material as the crucible 10 can be used.

The guide member 30 has a guide portion 30A and a support portion 30B. 30 A of guide parts are extended from the seed crystal installation part 21 to the crucible 10 side. In other words, the seed crystal 22 is arranged along the crystal growth direction of the seed crystal 22 installed in the seed crystal installation unit 21.
The diameter of the upper surface of the crucible 10 is larger than the diameter of the seed crystal installation part 21. Therefore, it is preferable that 30 A of guide parts are formed so that it may spread toward the crucible 10 side from the seed crystal installation part 21 side. The guide portion 30 </ b> A is preferably formed over the entire circumference of the seed crystal installation portion 21. By providing the guide part 30A over the entire circumference, the SiC single crystal 23 that grows from the seed crystal 22 installed in the seed crystal installation part 21 can be enlarged in any circumferential direction. When the guide part 30 </ b> A is inclined, the inclination angle is preferably the same even when the guide part 30 </ b> A is cut along any plane perpendicular to the seed crystal installation part 21. If the inclination angles are the same, the aperture expansion rate of the SiC single crystal 23 can be made constant.

  The support part 30B is not particularly limited as long as it can support the guide part 30A between the crucible 10 and the lid 20. For example, as shown in FIG. 1, the support portion 30B may be a rod-like member that is connected to a part of the end portion of the guide portion 30A and is lowered in the vertical direction from the end portion of the inclined surface 30A. Moreover, it is not restricted to a rod shape, A plate-shaped member may be sufficient and the tubular member connected to the whole end part of the guide part 30A may be sufficient. In order to avoid the outflow of gas, it is preferable to narrow the gap between the crucible 10 and the lid 20, and it is preferable to provide a tubular member.

  The connecting portion between the guide portion 30A and the support portion 30B preferably has a caulking structure. The caulking structure refers to a structure designed such that when a physical force is applied to the guide portion 30A, the connection portion between the guide portion 30A and the support portion 30B is tightened. For example, a screw in which the connection portion is threaded Examples include the structure. The guide portion 30A may be in physical contact with the SiC single crystal 23 on which the crystal grows, and in this case as well, the guide portion 30A can be prevented from falling off.

The guide member 30 controls the flow of source gas (Si, SiC ₂ , Si ₂ C, etc.) generated from the SiC single crystal growth source 11 between the crucible 10 and the lid 20. Therefore, the SiC single crystal 23 grows along the guide portion 30A.

  The surface of the guide member 30 is preferably coated with tantalum carbide. The guide member 30 is always exposed to the source gas in order to control the flow of the source gas. When the guide member 30 is used with the graphite exposed, the graphite may react with the raw material gas to cause deterioration damage. When the deterioration damage occurs, the guide member 30 may be perforated. In addition, the carbon powder peeled off due to deterioration is taken into the SiC single crystal 23, which leads to a cause of deterioration of the quality of the SiC single crystal 23. In contrast, tantalum carbide can withstand high temperatures and does not cause unnecessary reaction with the source gas. Therefore, high-quality SiC single crystal growth can be performed stably.

  The rotation driving unit 40 rotates the seed crystal installation unit 21 and / or the guide member 30. As the rotation drive means 40, for example, a drive motor provided outside can be used. In FIG. 1, an example in which a turntable 41 is provided below the lid 20 and the guide member 30 is illustrated. The rotary base 41 in FIG. 1 is connected to the lower end surface of the lid 20 and the lower end surface of the guide member 30. The rotation table 41 is rotated by the rotation driving means 40, and the rotation is interlocked with the lid body 20 and the guide member 30. Since the seed crystal installation part 21 is connected to the lid 20, it rotates together with the lid 20.

The connection between the turntable 41 and the lid 20 and / or the guide member 30 may be realized using any method. For example, you may form the recessed part which can engage | insert the lower end surface of the cover body 20 and / or the guide member 30 in the turntable 41. FIG. Further, the lid 20 and / or the guide member 30 may be provided with a clip or the like on the turntable 41 so that the turntable 41 can be sandwiched and supported. Moreover, it is good also as a caulking structure like the connection part of 30 A of guide parts, and the support part 30B.
The connection between the turntable 41 and the lid 20 and / or the guide member 30 does not need to be on the lower end surface as long as the lid 20 and / or the guide member 30 can be rotated.

  The seed crystal installation unit 21 may be directly rotated without being rotated through the lid 20. FIG. 2 is a schematic cross-sectional view enlarging the vicinity of the seed crystal installation portion of the SiC single crystal growth apparatus according to one aspect of the present invention. In FIG. 2, the rotating shaft 42 passes through the upper part of the lid 20 and is connected to the seed crystal installation part 21. By rotating the rotation shaft 42, the seed crystal installation unit 21 can be directly rotated.

  As the heating means 50 and the heat insulating material 60, generally known materials can be used. As the heating means 50, for example, a high frequency coil or the like can be used.

  Next, the growth process of the SiC single crystal 23 will be described, and the function of the SiC single crystal growth apparatus 100 will be described.

FIG. 3 is a diagram for explaining the function of the SiC single crystal growth apparatus according to one embodiment of the present invention, and is a schematic cross-sectional view in which a portion related to the flow of the source gas is enlarged.
The SiC single crystal growth raw material 11 heated by the heating means 50 is sublimated to generate a raw material gas. The generated source gas is supplied toward the seed crystal 22 installed in the seed crystal installation unit 21 as indicated by an arrow G1.

  A part of the source gas changes its flow direction along the guide portion 30a of the guide member 30 as indicated by an arrow G2. Therefore, the source gas is supplied by the guide member 30 so as to gather on the seed crystal 22. By supplying the source gas so as to collect from the surroundings to the seed crystal 22, the SiC single crystal 23 efficiently grows from the seed crystal 22 while expanding the diameter.

On the other hand, if the guide member 30 is not provided, the source gas supplied from the SiC single crystal growth source 11 is uniformly supplied upward as shown by an arrow G4 in FIG. Therefore, the diameter of the SiC single crystal 23 that grows from the seed crystal 22 hardly increases.
Further, if the guide member 30 is not provided, a large amount of polycrystals 24 grow in the upper corners of the lid 20 due to the raw material gas supplied to the other portions without being supplied to the seed crystal 22. That is, it means that many source gases are used to form the polycrystal 24, and the SiC single crystal 23 cannot be efficiently grown.

The polycrystal 24 that grows crystals at the upper corner 24 of the lid 20 is not completely absent in the SiC single crystal growth apparatus having the guide member 30. Although it is partially formed, it is less than the case where the guide member 30 is not provided.
On the other hand, in the SiC single crystal growth apparatus having the guide member 30, as shown in FIG. 5, the polycrystal 24 is formed on the surface of the guide member 30. The polycrystal 24 is particularly easy to grow a crystal at the end portion of the guide portion 30 a along the flow direction of the source gas in the guide member 30. As the crystal growth proceeds, the polycrystal 24 comes into contact with the SiC single crystal 23 to be integrated. Since the SiC single crystal 23 and the polycrystal 24 are different in crystallinity, when they are integrated, the contact surface is distorted. This distortion causes generation of defects and heterogeneous polymorphs in the SiC single crystal 23. Further, this strain can be a factor that causes cracks in the SiC single crystal 23.

  Here, the SiC single crystal 23 and the polycrystal 24 are integrated while performing crystal growth. Since the crystal growth of SiC is extremely gradual, they are not integrated unless their relative positions are the same for a certain period or longer. That is, it is necessary to relatively move the SiC single crystal 23 and the polycrystal 24 formed on the surface of the guide member 30 during the SiC crystal growth process.

In the SiC single crystal growth apparatus 100 according to the present embodiment, the seed crystal installation unit 21 and / or the guide member 30 is rotated by the rotation driving unit 40, whereby the positional relationship between the SiC single crystal 23 and the guide member 30 is relatively set. It is moving. Therefore, integration of SiC single crystal 23 and polycrystal 24 is inhibited, and a higher quality SiC single crystal can be obtained.
At this time, only one of the seed crystal installation part 21 and the guide member 30 may rotate, or both may rotate. In any case, the positional relationship between the SiC single crystal 23 and the polycrystal 24 formed on the surface of the guide member 30 moves relatively. When driving both the seed crystal installation part 21 and the guide member 30, it is preferable that the respective rotation directions are different. By making the respective rotation directions different from each other, it is possible to further inhibit the SiC single crystal 23 and the polycrystal 24 from being integrated.

  At this time, the rotational speed of the guide member 30 relative to the seed crystal 23 is preferably 0.1 rpm to 30 rpm. Since the growth rate of the SiC single crystal 23 is extremely slow, the integration of the polycrystal 24 and the SiC single crystal 23 can be sufficiently inhibited if there is a certain rotational speed. On the other hand, if the rotational speed is too high, the load on the SiC single crystal 23 becomes large, and the rotational driving means 24 for rotating it becomes unnecessarily excessive.

  Here, the source gas that has not been used for crystal growth of the SiC single crystal 23 stays in a region surrounded by the lid 20 and the crucible 10. A part of the staying source gas flows out from below along the space between the lid 20 and the crucible 10 as indicated by an arrow G3. The source gas flowing out from below is appropriately discharged out of the SiC single crystal growth apparatus 100 by an exhaust means (not shown).

  The SiC single crystal growth apparatus 100 has a high temperature at the bottom and a low temperature at the top. The lower portion is for sublimating the SiC single crystal growth raw material 11, and the upper portion is for growing the SiC single crystal 23 on the seed crystal 22. Since the source gas flows from the high temperature side toward the low temperature side, even if there is a gap below, the amount of the source gas flowing out can be minimized and efficient crystal growth can be performed. Further, the raw material gas discharged from below passes through a higher temperature region and then is discharged to the outside. That is, the source gas is hardly recrystallized and clogged between the lid 20 and the crucible 10. Therefore, the high-quality SiC single crystal 23 can be obtained without hindering the rotational drive of the seed crystal installation part 21 and / or the guide member 30.

The shortest distance between the guide member 30 and the side wall 20B of the lid 20 is preferably more than 0.01 mm and not more than 10 mm. “The shortest distance between the guide member 30 and the side wall 20B of the lid 20” means that the inclined surface 30A of the guide member 30 protrudes from the support portion 30B toward the side wall 20B of the lid 20 and It means the distance between the end and the side wall 20B of the lid 20. On the other hand, when the support portion 30B is connected to the end portion of the inclined surface 30A in the guide member 30, it means the distance between the support portion 30B and the side wall 20B of the lid body 20.
By securing the distance between the guide member 30 and the side wall 20B of the lid body 20 with a certain width, it is possible to suppress the source gas from being recrystallized during this period and inhibiting rotational driving. In addition, by narrowing the distance between the guide member 30 and the side wall 20B of the lid 20 as much as possible, the amount of source gas flowing out can be reduced, and crystal growth can be performed efficiently.
In addition, it is preferable that the distance between the side wall 20B of the lid 20 and the outer wall of the crucible 10 be as narrow as possible.

  The SiC single crystal growth apparatus 100 of this embodiment has a guide member 30 and relatively rotates the guide member 30 and the SiC single crystal 23 for crystal growth. Therefore, the diameter of the SiC single crystal 23 increases along the guide member 30, and the polycrystal 24 crystal-grown on the guide member 30 and the single crystal 23 grown from the seed crystal 22 are integrated. Can be inhibited. As a result, a long, large-diameter and high-quality SiC single crystal can be formed.

  Moreover, the SiC single crystal growth apparatus 100 of this embodiment discharge | releases source gas from the downward direction which becomes high temperature in the SiC single crystal growth apparatus 100. FIG. Therefore, recrystallization of the source gas can be inhibited, and the rotation of the guide member 30 and the SiC single crystal 23 on which the crystal grows can be maintained relatively.

[Second Embodiment]
FIG. 6 is a schematic cross-sectional view schematically showing a cross-section of the SiC single crystal growth crucible according to the second embodiment. The SiC single crystal growth apparatus 200 according to the second embodiment is different in that the crucible 10 and the guide member 30 of the SiC single crystal growth apparatus 100 according to the first embodiment are integrated into a crucible 70 with a guide portion. . In the following description, the description of the parts common to the above embodiment is omitted, and in each drawing used for the description, the same reference numerals are given to the same components as those in FIGS.

The crucible 70 with a guide has a storage part 70A for storing the SiC single crystal growth raw material 11 and an inclined part 70B that is inclined from the storage part 70A toward the seed crystal installation part 21 installed on the lid 20. The storage portion 70A corresponds to the crucible 10 of the SiC single crystal growth apparatus 100 of the first embodiment, and the inclined portion 70B corresponds to the guide member 30 of the SiC single crystal growth apparatus 100 of the first embodiment. That is, one end of the portion having the guide portion 30A of the guide member 30 of the first embodiment is connected to the open end portion of the crucible 10 of the first embodiment, which is equivalent to an integrated one. The connection between the crucible 10 and the guide member is not limited to the example in FIG. 6. For example, as shown in FIG. 7, the middle of the guide portion 30 </ b> A of the guide member 30 may be connected to the opening end portion of the crucible 10. .
The structure and material of the storage portion 70A and the inclined portion 70B can be the same as those of the crucible 10 and the guide portion 30A of the guide member 30 of the first embodiment.

In the SiC single crystal growth apparatus 200 of 2nd Embodiment, the seed crystal installation part 21 and the inclination part 70B rotate relatively. At this time, relative rotation of the seed crystal installation part 21 and the inclined part 70B may rotate the lid 20 having the seed crystal installation part 21 or rotate the support member 12 holding the crucible 70 with a guide part. You may let them. Moreover, you may rotate both of these.
Similar to the guide member 30 of the first embodiment, polycrystals adhere to the inclined portion 70B. For this reason, the SiC single crystal 23 that grows from the seed crystal 22 installed in the seed crystal installation unit 21 and the many attached to the inclination unit 70 by the relative rotation of the seed crystal installation unit 21 and the inclination unit 70B. It can suppress that a crystal contacts and integrates.

  In the SiC single crystal growth apparatus 200 of the second embodiment, the raw material gas retained between the crucible with guide 70 and the lid 20 passes between the crucible with guide 70 and the lid 20 and flows out from below. Since the lower part of the SiC single crystal growth apparatus 200 is at a high temperature for sublimating the SiC single crystal growth raw material 11, the amount of the raw material gas flowing out can be suppressed. Further, it is possible to suppress recrystallization in the process in which the source gas flows out.

The shortest distance between the outer wall of the crucible with guide part 70 and the inner wall of the lid 20 is preferably more than 0.01 mm and not more than 10 mm. The description of the shortest distance between the outer wall of the crucible with guide portion 70 and the inner wall of the lid body 20 in the second embodiment corresponds to the description of “the shortest distance between the guide member and the inner wall of the lid body” in the claims. To do. In the case of FIG. 6, it means the distance between the outer wall of the storage portion 70B (one end of the inclined portion 70B) and the inner wall of the lid body 20, and in the case of FIG. 7, the distance between one end of the inclined portion 70B and the lid body 20 is set. means.
By securing a certain distance between the outer wall of the crucible with guide part 70 and the inner wall of the lid body 20, it is possible to suppress the source gas from being recrystallized during this period and hindering rotational driving. In addition, by narrowing the distance between the outer wall of the crucible 70 with a guide part and the inner wall of the lid 20 as much as possible, the amount of source gas flowing out can be reduced and crystal growth can be performed efficiently. it can. When using the crucible 70 with a guide part, there is no need to consider the gap in which the guide part 30 in the first embodiment is provided, and the gap formed between the crucible 10 and the lid 20 can be made the smallest, Gas outflow can be minimized.

  The SiC single crystal growth apparatus 200 of the present embodiment has an inclined portion 70B, and relatively rotates the inclined portion 70B and the SiC single crystal 23 on which the crystal is grown. Therefore, the diameter of the SiC single crystal 23 increases along the inclined portion 70B, and the polycrystal 24 grown on the inclined portion 70B and the single crystal 23 grown from the seed crystal 22 are integrated. Can be inhibited. As a result, a long, large-diameter and high-quality SiC single crystal can be formed.

  Moreover, the SiC single crystal growth apparatus 100 of this embodiment flows out source gas from the downward direction which becomes high temperature in the SiC single crystal growth apparatus 200. FIG. Therefore, the outflow of the source gas from the reaction space can be suppressed. Moreover, since the outflow path becomes high temperature, recrystallization of the source gas is inhibited, and the inclined portion 70B and the SiC single crystal 23 on which the crystal grows can be kept relatively rotated.

  The preferred embodiments of the present invention have been described in detail above. However, the present invention is not limited to the specific embodiments, and various modifications can be made within the scope of the gist of the present invention described in the claims. Can be modified or changed.

  DESCRIPTION OF SYMBOLS 10 ... Crucible, 11 ... Raw material for SiC single crystal growth, 12 ... Support member, 20 ... Lid, 21 ... Seed crystal installation part, 22 ... Seed crystal, 23 ... SiC single crystal, 24 ... Polycrystal, 30 ... Guide member , 30a ... guide part, 40 ... rotation driving means, 41 ... rotary table, 42 ... rotating shaft, 50 ... heating means, 60 ... heat insulating material, 70 ... crucible with guide, 70A ... accommodating part, 70B ... tilting part, 100, 200 ... SiC single crystal growth apparatus

Claims (6)

A crucible capable of storing a raw material for SiC single crystal growth inside,
A lid that has a ceiling portion having a seed crystal installation portion at a position facing the crucible and a side wall surrounding the crucible, and covers the crucible;
A guide member having a guide part extending from the seed crystal installation part side toward the crucible side, and a support part for supporting the guide part;
An SiC single crystal growth apparatus comprising: a rotation driving unit that rotates the seed crystal installation unit and / or the guide member.   The SiC single crystal growth apparatus according to claim 1, wherein the guide member and the crucible are integrated.   3. The SiC single crystal growth apparatus according to claim 1, wherein the shortest distance between the guide member and the side wall of the lid is more than 0.01 mm and 10 mm or less.   The SiC single crystal growth apparatus according to any one of claims 1 to 3, wherein a surface of the guide member is coated with tantalum carbide. Storing a raw material for SiC single crystal growth in a crucible;
Disposing a guide member on the open end side of the crucible;
Installing a seed crystal in the seed crystal installation part of the lid;
Covering the crucible and the guide member with a lid provided with the seed crystal so that the seed crystal faces the SiC single crystal growth raw material;
And a step of sublimating an SiC single crystal growth raw material while relatively rotating the seed crystal and the guide member. The SiC single crystal growth method according to claim 5, wherein a rotation speed of the guide member with respect to the seed crystal is 0.1 rpm to 30 rpm.

Images