CN114574954A

CN114574954A - Crystal growing device

Info

Publication number: CN114574954A
Application number: CN202210095909.4A
Authority: CN
Inventors: 李远田; 陈俊宏; 吴亚娟
Original assignee: Jiangsu Jixin Semiconductor Silicon Research Institute Co Ltd
Current assignee: Jiangsu Jixin Advanced Materials Co ltd
Priority date: 2022-01-26
Filing date: 2022-01-26
Publication date: 2022-06-03
Anticipated expiration: 2042-01-26
Also published as: CN114574954B

Abstract

The invention discloses a crystal growth device, comprising: the device comprises a growing mechanism, a heating cavity and a powder source, wherein the growing mechanism is internally provided with the heating cavity; a connecting rod, at least part of which extends from the top wall of the growing mechanism into the heating chamber; the seed crystal base is arranged on the connecting rod and is provided with an installation surface, the included angle between the installation surface and the vertical direction is smaller than 90 degrees, and the heat conductivity of the seed crystal base is gradually reduced in the direction from top to bottom. According to the crystal growth device provided by the invention, the seed crystal base is arranged, the mounting surface on the seed crystal base is constructed to form an included angle of less than 90 degrees with the vertical direction, and the thermal conductivity of the mounting surface is gradually reduced in the direction from top to bottom, so that the defects in the crystal growth process are improved, and the stability of the crystal growth is improved.

Description

Crystal growing device

Technical Field

The invention relates to the technical field of crystal growth, in particular to a crystal growth device.

Background

In the related art, in the PVT growth system, the seed crystal is horizontally fixed or stuck in the growth chamber, which causes macro defects on the surface of the seed crystal or defects such as dislocations, micropipes, etc. in the seed crystal to penetrate the crystal in the direction of the axial temperature gradient during the growth process, thereby generating serious defects in the grown crystal.

Disclosure of Invention

The present invention is directed to solving at least one of the problems of the prior art. Therefore, an object of the present invention is to provide a crystal growth apparatus, in which defects occurring in a crystal growth process are improved and stability of a grown crystal form is improved by providing a seed crystal base and configuring a mounting surface on the seed crystal base to have an angle of less than 90 ° with a vertical direction, and a thermal conductivity of the mounting surface is gradually lowered in a direction from top to bottom.

The crystal growth apparatus according to an embodiment of the present invention includes: the device comprises a growing mechanism, a heating cavity and a powder source, wherein the growing mechanism is internally provided with the heating cavity; a connecting rod, at least part of which extends from the top wall of the growing mechanism into the heating chamber; the seed crystal base is arranged on the connecting rod and is provided with an installation surface, the included angle between the installation surface and the vertical direction is smaller than 90 degrees, the heat conductivity of the seed crystal base is gradually reduced in the direction from top to bottom, the seed crystal is suitable for being installed on the seed crystal base, and the growth surface of the seed crystal is parallel to the installation surface.

According to the crystal growth device provided by the embodiment of the invention, the installation surface arranged on the seed crystal base is constructed to form an included angle smaller than 90 degrees with the vertical direction, the powder source is parallel to the installation surface in the flow direction after being volatilized, compared with the traditional growth mechanism that the powder source sublimation direction is vertical to the surface of the seed crystal, the growth surface parallel to the seed crystal is provided with surface steps with higher density in unit area, the surface steps can be used as the starting points of the nucleation of the spiral dislocation steps, and meanwhile, the lower supersaturation degree of the advection growth surface is combined, so that the spiral dislocation step growth centers of a plurality of nucleation positions can appear on the growth surface of the seed crystal; from the view of crystallization kinetics, the ordered propulsion of atomic steps is ensured because the flow direction of the regulated growth components (stratosphere) is always opposite to the direction of the screw dislocation steps in the growth process. Therefore, the spiral step-parallel flow growth is possible along the surface of the advection type seed crystal, and therefore, the spiral dislocation step nucleation mechanism is the main growth mechanism, so that the design is favorable for avoiding the extension of defects such as micropipes and the like in the crystal, effectively reducing the crystal defects such as dislocation and the like in the crystal growth process and improving the crystal quality. In addition, the thermal conductivity of the seed crystal base is gradually reduced in the direction from top to bottom, and the thermal conductivity of the upper layer of the seed crystal base is higher, so that compared with the lower layer, the heat of the upper layer of the seed crystal base can be dissipated outwards quickly, the temperature of the upper layer of the seed crystal is reduced, the temperature difference between the upper layer of the seed crystal and gas is increased, and the growth rate is faster according to the principle that the temperature difference is larger, the crystal growth speed of the upper layer of the seed crystal is accelerated, and a slightly convex interface is maintained on the crystal growth surface.

According to one embodiment of the invention, the seed crystal susceptor comprises: the graphite base is connected with the connecting rod; the support pieces are configured to be multiple and arranged on the periphery of the graphite base, and the surfaces of the multiple support pieces, which face away from the graphite base, are configured as the mounting surfaces; wherein a plurality of the supporting members are arranged in sequence in an up-down direction and the thermal conductivity is gradually reduced.

According to one embodiment of the present invention, a plurality of the supporting members are configured as graphite sheets having different porosities from each other.

According to one embodiment of the invention, an inner crucible is arranged inside the heating chamber and defines a containing chamber with an open top for containing the powder source.

According to an embodiment of the present invention, the crystal growth apparatus further includes: the seed crystal base is provided with a central axis, the central axis is provided with a flow guide part, the flow guide part is arranged between the seed crystal base and the inner crucible, at least part of the peripheral wall of the flow guide part is formed into a flow guide surface, the flow guide surface faces away from the central axis of the flow guide part in an inclined manner in the direction from bottom to top, and the upper edge of the flow guide surface is just opposite to the lower edge of the mounting surface.

According to one embodiment of the invention, the growth mechanism comprises: a crucible assembly in which the heating cavity opened toward an outside is formed; the crucible cover, the crucible cover is suitable for and seals the heating chamber just the crucible is covered and is provided with and be used for with the exhaust hole that the heating chamber switched on with the outside, every exhaust hole with the growth face is just right.

According to one embodiment of the invention, the included angle between the mounting surface and the horizontal plane is theta, and the following conditions are satisfied: theta is more than or equal to 75 degrees and less than or equal to 90 degrees

According to one embodiment of the invention, the connecting rod is rotatably arranged to drive the seed crystal susceptor to rotate in the heating cavity.

According to one embodiment of the invention, the periphery of the seed crystal base is provided with a plurality of mounting surfaces, and the mounting surfaces are arranged along the circumferential direction of the seed crystal base.

According to an embodiment of the present invention, the seed crystal is formed in a hollow ring shape, the seed crystal is fitted over the seed crystal base, a first fitting hole is provided on the fitting surface of the seed crystal base, a second fitting hole corresponding to the first fitting hole is provided on the fitting surface of the seed crystal, and the crystal growing apparatus further includes: and the mounting pin is suitable for being arranged in the first mounting hole and the second mounting hole in a penetrating mode so as to fix the seed crystal to the seed crystal base.

According to an embodiment of the present invention, the seed crystal base is further provided with a third mounting hole extending in an axial direction of the seed crystal base, the third mounting hole communicating with the plurality of first mounting holes, the mounting pin being movably disposed in the first mounting hole, the crystal growing apparatus further comprising: the matching pin is suitable for matching with the third mounting hole and driving the mounting pin positioned in the third mounting hole to move along the first mounting hole, so that one end of the mounting pin, which is far away from the matching pin, is inserted into the second mounting hole.

According to an embodiment of the present invention, an upper end surface of the fitting pin is formed as a tapered surface, and an end of the mounting pin facing the third mounting hole is provided with a slope surface fitted with the tapered surface.

Additional aspects and advantages of the invention will be set forth in part in the description which follows and, in part, will be obvious from the description, or may be learned by practice of the invention.

Drawings

The above and/or additional aspects and advantages of the present invention will become apparent and readily appreciated from the following description of the embodiments, taken in conjunction with the accompanying drawings of which:

FIG. 1 is a schematic structural diagram of a crystal growing apparatus according to an embodiment of the present invention;

FIG. 2 is a schematic structural diagram of a crystal growing apparatus according to another embodiment of the present invention;

FIG. 3 is a top view of a crystal growing apparatus according to one embodiment of the present invention;

FIG. 4 is a schematic structural view of a seed crystal according to an embodiment of the present invention;

FIG. 5 is a top view of the inner crucible and the connecting rods according to one embodiment of the present invention;

FIG. 6 is a schematic flow diagram of silicon carbide gas in an embodiment in accordance with the invention;

FIG. 7 is a schematic view of a multi-spiral step nucleation site during seed growth according to an embodiment of the present invention;

FIG. 8 is a schematic diagram of nucleation of multiple stable helical step-parallel flow growth mechanisms during seed growth according to an embodiment of the present invention;

FIG. 9 is a schematic view of a plurality of stable spiral step nucleation centers gradually fusing to form a single crystal plane during seed crystal growth in accordance with an embodiment of the present invention;

FIG. 10 is a schematic view of an initial stage of seed growth according to one embodiment of the present invention;

FIG. 11 is a schematic view of the end of the growth of a seed crystal according to one embodiment of the invention;

FIG. 12 is a schematic view of a seed pedestal according to another embodiment of the invention;

FIG. 13 is a schematic view of the mating of a seed crystal pedestal with a mounting pin according to one embodiment of the present invention;

FIG. 14 is a schematic structural view of a mating pin according to one embodiment of the present invention;

FIG. 15 is a schematic view of the attachment of a graphite susceptor to a mounting pin according to one embodiment of the present invention;

FIG. 16 is a schematic view of the structure of a seed crystal according to one embodiment of the present invention;

FIG. 17 is a schematic view of the mating of a seed crystal with a seed pedestal according to one embodiment of the invention.

Reference numerals:

a crystal growth apparatus 1;

growth mechanism 11, crucible assembly 111, graphite crucible 1111, quartz crucible 1112, crucible cover 112, exhaust hole 113;

a connecting rod 12;

a seed crystal susceptor 13, a mounting face 131, a graphite susceptor 132, a support 133, a first mounting hole 134, a third mounting hole 135,

inner crucible 14, deflector 15, deflector surface 151, mounting pin 16, mating pin 17,

seed crystal 2, second mounting hole 21, growth surface 22.

Detailed Description

Reference will now be made in detail to embodiments of the present invention, examples of which are illustrated in the accompanying drawings, wherein like or similar reference numerals refer to the same or similar elements or elements having the same or similar function throughout. The embodiments described below with reference to the accompanying drawings are illustrative only for the purpose of explaining the present invention, and are not to be construed as limiting the present invention.

A crystal growth apparatus 1 according to an embodiment of the present invention is described below with reference to fig. 1 to 17.

The crystal growth apparatus 1 according to the present application includes: growth mechanism 11, connecting rod 12, seed crystal base 13 can be used for fixed seed crystal 2, growth mechanism 11 is inside to be formed with the heating chamber, the intracavity is equipped with the powder source in the heating chamber, connecting rod 12 at least part stretches into to the heating chamber from growth mechanism 11's roof, seed crystal base 13 sets up in connecting rod 12, be formed with installation face 131 on seed crystal base 13, installation face 131 is less than 90 with the contained angle of vertical direction, seed crystal base 13 is at the direction from top to bottom upwards heat conductivity reduction gradually, seed crystal 2 is suitable for and installs on seed crystal base 13, and the growth face 22 of seed crystal 2 is parallel with installation face 131.

After the powder source is volatilized, the powder source is parallel to the mounting surface 131 in the flowing direction, compared with a traditional growth mechanism that the powder source sublimes and the direction of the powder source is vertical to the surface of the seed crystal, the growth surface parallel to the seed crystal 2 is provided with surface steps with higher density in unit area, the surface steps can be used as the starting points of the nucleation of the spiral dislocation steps, and meanwhile, the lower supersaturation degree of the advection growth surface is combined, so that the spiral dislocation step growth centers of a plurality of nucleation positions can appear on the growth surface of the seed crystal; from the view of crystallization kinetics, the ordered propulsion of atomic steps is ensured because the flow direction of the regulated growth components (stratosphere) is always opposite to the direction of the screw dislocation steps in the growth process. Therefore, the spiral step-parallel flow growth is possible along the surface of the advection type seed crystal 2, so the spiral dislocation step nucleation mechanism is the main growth mechanism, the design is favorable for avoiding the extension of defects such as micropipes and the like in the crystal, effectively reducing the crystal defects such as dislocation and the like in the crystal growth process and improving the crystal quality.

Specifically, as shown in fig. 6, the seed crystal 2 can be fixed on the mounting surface 131, compared with the conventional seed crystal growth mode, the present application sets the mounting surface 131 to extend in the vertical direction, and keeps the included angle between the mounting surface 131 and the vertical direction less than 90 degrees, so that the silicon carbide gas is consistent with the extending direction of the mounting surface 131 in the flow direction, and by the design of the quasi-asymmetric flow field of parallel flow guiding on the surface of the seed crystal 2, the flow direction and the component flow density of gas growth components can be regulated and controlled in the growth process, so as to establish a significant concentration difference between the bottom and the top of the seed crystal 2, that is, the gas sublimated from the powder source preferentially flows through the bottom of the seed crystal 2 and further reaches a supersaturated state on the bottom surface of the seed crystal 2, at this time, the gas flowing through the top of the seed crystal 2 is less, the supersaturation degree of the growth front on the top surface of the seed crystal 2 is lower, and for the top of the seed crystal 2, the concentration of the sublimated gas is limited, the supersaturation is small and the growth speed is slow.

As shown in fig. 7, the vertically fixed seed crystal 2 has a higher density of surface steps per unit area parallel to the surface of the seed crystal 2 by promoting a reduction in the radial temperature gradient of the crystal surface and by having surface steps that serve as starting points for the nucleation of screw dislocation steps in comparison with a growth mechanism in which the sublimation direction of the silicon carbide source powder is perpendicular or nearly perpendicular to the surface of the seed crystal 2 macroscopically, and at the same time, in combination with a less supersaturation of the advection growth surface, screw dislocation step growth centers at a plurality of nucleation sites occur at the surface of the seed crystal 2.

As shown in fig. 8, from the view of crystallization kinetics, since the flow direction of the regulated growth components (stratosphere) is always opposite to the direction of the screw dislocation step in the growth process, the ordered advancement of the atomic step is ensured; therefore, along the surface of the advection type seed crystal 2, the spiral step-parallel flow growth becomes possible, and the spiral dislocation step nucleation mechanism is the main growth mechanism, so that the mode of vertically sticking the seed crystal 2 is favorable for avoiding the deepening of the defects such as micropipes and the like in the crystal and simultaneously is favorable for the stability of the crystal form.

Subsequently, as shown in fig. 9, on the surface of the seed crystal, growth is initiated by screw dislocation steps caused by different gas saturation degrees, a plurality of growth centers begin to appear, and slowly expand to form a hill-shaped protrusion to form respective growth surfaces, and finally, the growth platforms expand longitudinally and slowly fuse together to form a complete single crystal plane.

In addition, through setting up seed crystal base 13 and heat conductivity reduces gradually in the direction from top to bottom, the installation face 131 that surface temperature gradient changes has been formed, because the heat conductivity of seed crystal base 13 upper position is higher, compare with the lower floor, the heat of seed crystal 2 upper position can outwards dissipate fast, thereby reduce the temperature of upper seed crystal 2, the difference in temperature between upper seed crystal 2 and the gas has been increased, according to the big faster principle of growth rate of the difference in temperature, seed crystal upper position crystal growth speed has been accelerated, make the crystal growth face maintain a little protruding interface, effectively reduce crystal defects such as dislocation that appear in the crystal growth process, the crystal quality is improved.

According to the crystal growth device 1 provided by the embodiment of the invention, the installation surface 131 of the seed crystal base 13 is constructed to form an included angle smaller than 90 degrees with the vertical direction, so that the powder source is volatilized and then is parallel to the installation surface 131 in the flow direction, compared with a traditional growth mechanism that the sublimation direction of the powder source is vertical to the surface of the seed crystal, the growth surface parallel to the seed crystal 2 is provided with surface steps with higher density in unit area, the surface steps can be used as the starting points of nucleation of the screw dislocation steps, and meanwhile, the lower supersaturation degree of the advection growth surface is combined, so that the screw dislocation step growth centers of a plurality of nucleation positions can appear on the growth surface of the seed crystal; from the view of crystallization kinetics, the ordered propulsion of atomic steps is ensured because the flow direction of the regulated growth components (stratosphere) is always opposite to the direction of the screw dislocation steps in the growth process. Therefore, the spiral step-parallel flow growth is possible along the surface of the advection type seed crystal 2, so the spiral dislocation step nucleation mechanism is the main growth mechanism, the design is favorable for avoiding the extension of defects such as micropipes and the like in the crystal, effectively reducing the crystal defects such as dislocation and the like in the crystal growth process and improving the crystal quality.

According to an embodiment of the present invention, the seed crystal susceptor 13 includes a graphite susceptor 132 and a support 133, the graphite susceptor 132 is connected to the connecting rod 12, the support 133 is configured in plural and is provided at an outer periphery of the graphite susceptor 132, a surface of the plurality of supports 133 facing away from the graphite susceptor 132 is configured as the mounting surface 131, the plurality of supports 133 are sequentially arranged in a direction from top to bottom and have a gradually decreasing thermal conductivity, such that the seed crystal susceptor 13 is configured as a gradually decreasing thermal conductivity in the direction from top to bottom.

As shown in fig. 12, according to an embodiment of the present invention, the supporting member 133 is configured as a graphite sheet, and a plurality of graphite sheets are sequentially arranged on the graphite base 132 in a low-to-high direction and sequentially improve thermal conductivity. Each of the supporting members 133 may be configured as a graphite sheet having different porosity, and the thermal conductivity is gradually reduced from top to bottom in sequence, and when the supporting material is disposed between the seed crystal 2 and the graphite base 132, the heat dissipation from the top end of the seed crystal 2 is fast, the temperature is reduced, and the temperature difference is large, so that the growth rate of the crystal is fast; on the contrary, the heat dissipation of the bottom end of the seed crystal 2 is slow, the temperature is high, the temperature difference is relatively small, and the growth rate of the crystal is slowed down. Therefore, multi-screw dislocation step nucleation is realized, the crystal defects such as dislocation and the like in the crystal growth process are effectively reduced, and the crystal quality is improved.

As shown in fig. 1 and 2, according to one embodiment of the present invention, an inner crucible 14 with an open top is provided inside the heating chamber, and the inner crucible 14 defines a containing chamber with an open top for containing the powder source. For example, in one example of the invention, the inner crucible 14 is located directly below the seed crystal 2 and has an interior adapted to contain silicon carbide powder. After the growth mechanism 11 is operated, the silicon carbide powder in the inner crucible 14 forms silicon carbide gas, and the silicon carbide gas gradually flows upward, and the silicon carbide gas flows in parallel along the growth surface of the seed crystal 2, thereby growing a silicon carbide crystal.

According to one embodiment of the invention, the crystal growth apparatus 1 further comprises a flow guide 15, the flow guide 15 is arranged between the seed crystal base 13 and the inner crucible 14, at least part of the outer peripheral wall of the flow guide 15 is formed into a flow guide surface 151, the flow guide surface 151 extends obliquely in a direction departing from the central axis of the flow guide 15 in the direction from bottom to top, and the upper edge of the flow guide surface 151 is opposite to the lower edge of the mounting surface 131.

The cross section of the seed crystal susceptor 13 may be constructed in a rectangular or polygonal structure so that a plurality of mounting faces 131 are provided on the seed crystal susceptor 13, the plurality of mounting faces 131 being arranged in the circumferential direction of the seed crystal susceptor, thereby improving the production efficiency of the crystal growth apparatus 1, while the structure of the inner crucible 14 does not match the cross section of the seed crystal susceptor 13, and the flow rate of the silicon carbide gas is not well concentrated. For this reason, by providing the flow guide 15 and flowing the powder source gas toward the mounting surface 131 by the flow guide surface 151, the concentration and flow rate of the powder source gas at the bottom of the mounting surface 131 are increased.

In one embodiment of the present invention, the inner crucible 14 may be configured as a circular groove, and the center of the inner crucible 14 is located right below the geometric center of the cross section of the seed crystal susceptor 13, the connecting rod 12 may be rotatably disposed, and the rotation axis of the connecting rod 12 passes through the center of the inner crucible 14, so that the growth speed of the seed crystal 2 disposed on each mounting surface 131 of the seed crystal susceptor 13 is uniform after the connecting rod 12 rotates, thereby reducing the difference in the growth speed of the seed crystal 2 caused by the different concentrations of the powder source gases in the heating chamber and improving the quality of the crystal generated by the crystal growth apparatus 1.

As shown in fig. 1 and 2, according to one embodiment of the present invention, a flow guide 15 is provided below the graphite susceptor 132 to facilitate the transport of the sublimated powder source along the surface of the seed crystal 2, and the lower portion of the surface of the seed crystal 2 has a gas flow rate of higher density per unit than that of the conventional bonding manner in which the surface of the seed crystal is perpendicular (or nearly perpendicular) to the growth direction, so that the macroscopic growth surface of the crystal appears more prominent with respect to the middle-upper portion of the seed crystal 2.

According to one embodiment of the present invention, growth mechanism 11 comprises: a crucible assembly 111 and a crucible cover 112, a heating cavity opened toward the outside is formed in the crucible assembly 111; the crucible cover 112 is suitable for sealing the heating cavity, the crucible cover 112 is provided with exhaust holes 113 for communicating the heating cavity with the outside, and each group of exhaust holes 113 is opposite to the seed crystal growth surface. The gas exhaust hole 113 can promote the flow of the powder source gas and increase the flow of the gas, thereby increasing the growth rate of the crystal and facilitating the realization of the parallel flow of the sublimated gas phase along the surface of the seed crystal 2.

Further, the crucible assembly 111 includes: graphite crucible 1111 and quartz crucible 1112, graphite crucible 1111 limits the above-mentioned heating chamber, and quartz crucible 1112 is between graphite crucible 1111 and exterior space apart, and quartz crucible 1112 is used for keeping warm thermal-insulated to graphite crucible 1111.

As shown in fig. 12, according to an embodiment of the present invention, the mounting surface 131 is at an angle θ with respect to the horizontal plane, and satisfies: theta is more than or equal to 75 degrees and less than or equal to 90 degrees. It can be understood that the growth quality can be further improved by setting the included angle between the mounting surface 131 and the horizontal plane to be 75-90 degrees, and the consumption of the powder source in the crystal growth process can be reduced to a certain extent. In particular, in some examples of the invention, the mounting face 131 may be angled at 76 °, 78 °, 80 °, 82 °, 84 °, 86 °, 88 °, or 90 ° from horizontal.

According to one embodiment of the present invention, the connecting rod 12 is rotatably disposed to rotate the seed susceptor 13 in the heating chamber. The connecting rod 12 is used for driving the seed crystal 2 to rotate, so that the powder source gas passing through each growth surface of the seed crystal 2 in the growth process is more balanced, and the growth stability of the seed crystal 2 and the quality of a final product are improved. In one example of the invention, the connecting rod 12 may be configured as a graphite shaft.

As shown in fig. 13 to 17, according to an embodiment of the present invention, the seed crystal 2 is formed in a hollow ring shape, the seed crystal 2 is fitted on the seed crystal base 13, the fitting surface 131 of the seed crystal base 13 is provided with a first fitting hole 134, the fitting surface of the seed crystal 2 is provided with a second fitting hole 21 corresponding to the first fitting hole 134, and the crystal growing apparatus 1 further includes: and a mounting pin 16, wherein the mounting pin 16 is suitable for being arranged in the first mounting hole 134 and the second mounting hole 21 in a penetrating way so as to fix the seed crystal 2 on the seed crystal base 13.

On traditional seed crystal mounting means adopted the form that bonds to be fixed in the seed crystal base, traditional sticky mode leaded to the seed crystal installation inconvenient, at the in-process of crystal growth, and traditional sticky mode seed crystal and the connection between the seed crystal base are unreliable, had the risk that the seed crystal drops. This application utilizes mounting pin 16 to be fixed in the reliability that seed crystal 2 installed on seed crystal base 13 with seed crystal 2, has reduced the risk that seed crystal 2 drops.

In some embodiments, the seed crystal 2 is divided into four parts, and the seed crystal base 13 is configured as a cube, four mounting surfaces 131 on the circumference of the seed crystal base 13 are respectively connected with the seed crystals 2 of the corresponding parts, the four parts of seed crystals 2 can be configured as a split type and respectively matched with the corresponding mounting surfaces 131, the four parts of seed crystals 2 can be configured as an integral structure, and every four parts of seed crystals 2 are connected end to be arranged on the seed crystal base 13 in a surrounding manner.

As shown in FIG. 4, according to one embodiment of the present invention, the seed crystal 2 is constructed in a hollow-centered cubic structure, four edges of the cube are recessed toward the inside to form an arc-shaped inverted groove, and the arc-shaped guide groove can prevent the powder source gas from accumulating at the inverted corner of the cube.

According to an embodiment of the present invention, the second mounting hole 21 is configured as a blind hole, and the seed crystal base 13 is further provided with a third mounting hole 135, the third mounting hole 135 extending in the axial direction of the seed crystal base 13, the third mounting hole 135 communicating with the plurality of first mounting holes 134, the mounting pins 16 being movably disposed in the first mounting holes 134, the crystal growing apparatus 1 further comprising: and the matching pin 17, wherein the matching pin 17 is suitable for matching with the third mounting hole 135 and is suitable for driving the mounting pin 16 positioned in the third mounting hole 135 to move in the first mounting hole 134 so as to match with the second mounting hole 21.

During the assembly process, the mounting pin 16 can be arranged in the first mounting hole 134 in advance, and part of the mounting pin 16 can extend into the third mounting hole 135, after the matching pin 17 is further inserted into the third mounting hole 135, the matching pin 17 contacts with part of the mounting pin 16 entering into the third mounting hole 135, and drives the mounting pin 16 to protrude outwards, so that one end of the mounting pin 16 departing from the third mounting hole 135 enters into the second mounting hole 21 of the seed crystal 2, and the seed crystal 2 is fixed. By adopting the matching mode, the seed crystal 2 is simple and convenient to install, the installation efficiency of the seed crystal 2 is improved, and the seed crystal 2 is easier to take out after the growth is completed.

As shown in fig. 14, according to one embodiment of the present invention, the upper end surface portion of the fitting pin 17 is formed as a tapered surface, and one end of the mounting pin 16 facing the third mounting hole 135 is provided with a slope surface that fits the tapered end portion of the fitting pin 17. The end of the fitting pin 17 may be configured to be tapered, and the tapered surface is formed on the outer periphery of the end, and when the tapered surface of the fitting pin 17 contacts the inclined surface of the mounting pin 16, the driving force of the fitting pin 17 in the direction along the third mounting hole 135 may be converted into the driving force of the mounting pin 16 in the extending direction of the first mounting hole 134 by the engagement of the tapered surface and the inclined surface.

Further, the first mounting holes 134 are configured to be plural and disposed perpendicular to the corresponding mounting surfaces 131, and the first mounting holes 134 may be configured to be plural and spaced apart from each other on the corresponding mounting surfaces 131.

According to an embodiment of the present invention, the third mounting hole 135 may extend in a vertical direction and be perpendicular to the extending direction of the first mounting hole 134, and the third mounting hole 135 may be provided at the bottom of the seed crystal susceptor 13 to facilitate a user's manipulation, so that the process of transferring the fitting pin 17 into the third mounting hole 135 is facilitated.

In another embodiment of the present invention, a thermal insulation member is further disposed at the periphery of the growth mechanism 11, and the thermal insulation member may be configured as a graphite felt, and an induction coil for heating is disposed at the periphery of the graphite felt, so as to heat the seed crystal 2 and the powder source in the heating chamber, and generate the powder source gas in the heating chamber.

In the description of the present invention, it is to be understood that the terms "central," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," "circumferential," and the like are used in the orientations and positional relationships indicated in the drawings for convenience in describing the invention and to simplify the description, and are not intended to indicate or imply that the referenced device or element must have a particular orientation, be constructed and operated in a particular orientation, and are not to be considered limiting of the invention.

In the description of the present invention, "the first feature" and "the second feature" may include one or more of the features.

In the description of the present invention, "a plurality" means two or more.

In the description of the present invention, the first feature being "on" or "under" the second feature may include the first and second features being in direct contact, and may also include the first and second features being in contact with each other not directly but through another feature therebetween.

In the description of the invention, "above", "over" and "above" a first feature in a second feature includes the first feature being directly above and obliquely above the second feature, or simply means that the first feature is higher in level than the second feature.

In the description herein, references to the description of the term "one embodiment," "some embodiments," "an illustrative embodiment," "an example," "a specific example," or "some examples" or the like mean that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the invention. In this specification, the schematic representations of the terms used above do not necessarily refer to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

While embodiments of the invention have been shown and described, it will be understood by those of ordinary skill in the art that: various changes, modifications, substitutions and alterations can be made to the embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the claims and their equivalents.

Claims

1. A crystal growth apparatus, comprising:

the device comprises a growing mechanism, a heating cavity and a powder source, wherein the growing mechanism is internally provided with the heating cavity;

a connecting rod, at least part of which extends from the top wall of the growing mechanism into the heating chamber;

the seed crystal base is arranged on the connecting rod and is provided with an installation surface, the included angle between the installation surface and the vertical direction is smaller than 90 degrees, the heat conductivity of the seed crystal base is gradually reduced in the direction from top to bottom, the seed crystal is suitable for being installed on the seed crystal base, and the growth surface of the seed crystal is parallel to the installation surface.

2. The crystal growth apparatus of claim 1, wherein the seed pedestal comprises:

the graphite base is connected with the connecting rod;

the support pieces are configured to be multiple and arranged on the periphery of the graphite base, and the surfaces of the multiple support pieces, which face away from the graphite base, are configured as the mounting surfaces; wherein

The plurality of the supporting pieces are arranged in sequence in the direction from top to bottom, and the thermal conductivity is gradually reduced.

3. The crystal growth apparatus of claim 2, wherein the plurality of support members are constructed of graphite sheets having different porosities from each other.

4. A crystal growth apparatus as claimed in claim 1, wherein an inner crucible is disposed within the heating chamber, the inner crucible defining a holding chamber open at the top for holding the powder source.

5. The crystal growth apparatus of claim 4, further comprising: the seed crystal base is provided with a central axis, the central axis is provided with a flow guide part, the flow guide part is arranged between the seed crystal base and the inner crucible, at least part of the peripheral wall of the flow guide part is formed into a flow guide surface, the flow guide surface faces away from the central axis of the flow guide part in an inclined manner in the direction from bottom to top, and the upper edge of the flow guide surface is just opposite to the lower edge of the mounting surface.

6. The crystal growth apparatus of claim 1, wherein the growth mechanism comprises:

a crucible assembly in which the heating cavity opened toward an outside is formed;

the crucible cover, the crucible cover is suitable for and seals the heating chamber just the crucible is covered and is provided with and be used for with the exhaust hole that the heating chamber switched on with the outside, every exhaust hole with the growth face is just right.

7. The crystal growth apparatus of claim 1, wherein the mounting surface and the horizontal plane form an angle θ that satisfies: theta is more than or equal to 75 degrees and less than or equal to 90 degrees

8. The crystal growth apparatus of claim 1, wherein the linkage is rotatably disposed to rotate the seed pedestal within the heating chamber.

9. The crystal growth apparatus of claim 1, wherein the seed crystal susceptor has a plurality of mounting surfaces provided on an outer periphery thereof, the plurality of mounting surfaces being arranged in a circumferential direction of the seed crystal susceptor.

10. The crystal growth apparatus as claimed in claim 9, wherein the seed crystal is formed in a hollow ring shape, the seed crystal is fitted over the seed crystal base, a first fitting hole is provided on the fitting surface of the seed crystal base, a second fitting hole corresponding to the first fitting hole is provided on the fitting surface of the seed crystal, and the crystal growth apparatus further comprises: and the mounting pin is suitable for being arranged in the first mounting hole and the second mounting hole in a penetrating mode so as to fix the seed crystal to the seed crystal base.

11. The crystal growing apparatus of claim 10 wherein the seed pedestal is further provided with a third mounting hole extending in an axial direction of the seed pedestal, the third mounting hole being in communication with the plurality of first mounting holes, the mounting pin being movably disposed in the first mounting holes, the crystal growing apparatus further comprising: the matching pin is suitable for matching with the third mounting hole and driving the mounting pin positioned in the third mounting hole to move along the first mounting hole, so that one end of the mounting pin, which is far away from the matching pin, is inserted into the second mounting hole.

12. The crystal growth apparatus of claim 11, wherein an upper end surface of the fitting pin is formed as a tapered surface, and an end of the mounting pin facing the third mounting hole is provided with a slope surface fitted with the tapered surface.