Aluminum nitride growth device

Abstract

The invention provides an aluminum nitride growth device. The aluminum nitride growth device comprises a crucible, a raw material crucible assembly arranged in the middle of the crucible, a first fixing structure and a second fixing structure, wherein the first fixing structure and the second fixing structure are arranged on the upper side and the lower side of the raw material crucible assembly respectively in the longitudinal direction; wherein the raw material crucible assembly divides an inner cavity of the crucible into a first sublimation area and a second sublimation area which are arranged in the longitudinal direction and are communicated with each other; the raw material crucible assembly comprises a raw material crucible used for containing an aluminum nitride raw material. The first fixing structure is used for fixing the first seed crystal and exposing the growth surface of the first seed crystal to the first sublimation area; the second fixing structure is used for fixing the second seed crystal and exposing the growth surface of the second seed crystal to the second sublimation area; the aluminum nitride growth device disclosed by the invention realizes simultaneous growth of two aluminum nitride crystal ingots in a single furnace, and improves the production efficiency.

Description

Technical Field

[0001] The invention relates to the technical field of crystal growth, and in particular to an aluminum nitride growth device. Background Art

[0002] Aluminum nitride (AlN) has become a new generation of ultra-wide bandgap semiconductors and a key strategic new material with great potential due to its excellent performance. The physical vapor transport process (PVT) is the dominant method for growing high-quality bulk AlN crystals. However, the traditional physical vapor transport process can only grow one aluminum nitride ingot per furnace, which has low production efficiency.

[0003] It should be noted that the above introduction to the background technology is only for the convenience of providing a clear and complete description of the technical solutions of the present invention and for the convenience of understanding by those skilled in the art. It cannot be considered that the above technical solutions are well known to those skilled in the art simply because these solutions are described in the background technology section of the present invention. Summary of the invention

[0004] The purpose of the present invention is to disclose an aluminum nitride growth device for solving the many defects existing in the device for preparing crystal ingots by physical vapor transport method in the prior art, especially for realizing the simultaneous growth of two aluminum nitride crystal ingots in a single furnace to improve production efficiency.

[0005] To achieve the above-mentioned object, the present invention provides an aluminum nitride growth device, comprising: a crucible, a raw material crucible assembly disposed in the middle of the crucible, and a first fixing structure and a second fixing structure disposed at upper and lower sides of the raw material crucible assembly in the longitudinal direction, respectively;

[0006] Wherein, the raw material crucible assembly divides the inner cavity of the crucible into a first sublimation zone and a second sublimation zone which are arranged in the longitudinal direction and are interconnected;

[0007] The raw material crucible assembly comprises a raw material crucible, and the raw material crucible is used to hold aluminum nitride raw materials;

[0008] The first fixing structure is used to fix the first seed crystal and expose the growth surface of the first seed crystal to the first sublimation zone; the second fixing structure is used to fix the second seed crystal and expose the growth surface of the second seed crystal to the second sublimation zone.

[0009] As a further improvement of the present invention, the material of the crucible is pure tungsten.

[0010] As a further improvement of the present invention, a first guiding structure is constructed inside the first fixed structure for guiding the gas phase material generated by the sublimation of the aluminum nitride raw material in the raw material crucible to the growth surface of the first seed crystal in the first sublimation zone;

[0011] A second guiding structure for guiding the gaseous substances generated by the sublimation of the aluminum nitride raw material in the raw material crucible to the growth surface of the second seed crystal in the second sublimation zone is constructed inside the second fixed structure.

[0012] As a further improvement of the present invention, the aluminum nitride growth device further includes: a first flow guide cover disposed longitudinally between the raw material crucible and the first fixed structure, and a second flow guide cover disposed longitudinally between the raw material crucible and the second fixed structure;

[0013] The first flow guide cover is used to guide the gaseous substances generated by the sublimation of the aluminum nitride raw material in the raw material crucible to the growth surface of the first seed crystal in the first sublimation zone, and the second flow guide cover is used to guide the gaseous substances generated by the sublimation of the aluminum nitride raw material in the raw material crucible to the growth surface of the second seed crystal in the second sublimation zone.

[0014] As a further improvement of the present invention, a first guide structure is constructed inside the first fixed structure for guiding the gaseous substances generated by the sublimation of the aluminum nitride raw material in the raw material crucible to the growth surface of the first seed crystal in the first sublimation zone; the aluminum nitride growth device also includes: a second flow guide cover arranged in the longitudinal direction between the raw material crucible and the second fixed structure, the second flow guide cover is used to guide the gaseous substances generated by the sublimation of the aluminum nitride raw material in the raw material crucible to the growth surface of the second seed crystal in the second sublimation zone;

[0015] Alternatively, the aluminum nitride growth device also includes: a first flow guide cover longitudinally arranged between the raw material crucible and the first fixed structure, the first flow guide cover is used to guide the gaseous substances generated by the sublimation of the aluminum nitride raw material in the raw material crucible to the growth surface of the first seed crystal in the first sublimation zone; and a second guide structure is constructed inside the second fixed structure for guiding the gaseous substances generated by the sublimation of the aluminum nitride raw material in the raw material crucible to the growth surface of the second seed crystal in the second sublimation zone.

[0016] As a further improvement of the present invention, a first clamping groove for holding the first seed crystal is constructed in the middle of the first fixing structure, and the inner diameter of the first guiding structure decreases from the bottom of the first fixing structure to one side of the first clamping groove;

[0017] A second clamping groove for holding the second seed crystal is constructed in the middle of the second fixing structure, and the inner diameter of the second guide structure decreases from the bottom of the second fixing structure to one side of the second clamping groove.

[0018] As a further improvement of the present invention, the inner diameter of the first flow guide cover decreases from the raw material crucible to one side of the first fixed structure, and a plurality of first through holes are formed on one side of the first flow guide cover close to the growth surface of the first seed crystal;

[0019] The inner diameter of the second flow guide cover decreases gradually from the raw material crucible to one side of the second fixed structure, and a plurality of second through holes are formed on one side of the second flow guide cover close to the growth surface of the second seed crystal.

[0020] As a further improvement of the present invention, the crucible comprises: a crucible bottom, a crucible cover, and a crucible barrel with openings at both ends and adjustable height, the bottom of the crucible barrel is mounted on the crucible bottom, and the crucible cover is mounted on the top opening of the crucible barrel;

[0021] The aluminum nitride growth device also includes: a first sleeve and a second sleeve which are continuously arranged in the longitudinal direction and attached to the inner wall of the crucible; the first sleeve extends in the longitudinal direction to the installation gap between the crucible cover and the crucible barrel, and the second sleeve extends in the longitudinal direction to the installation gap between the crucible barrel and the crucible bottom.

[0022] As a further improvement of the present invention, the raw material crucible assembly further includes a support portion protruding outwardly in the circumferential direction to extend between the first sleeve and the second sleeve, and the first sleeve and the second sleeve abut against the outer circumference of the support portion in the longitudinal direction;

[0023] The first sleeve extends in the longitudinal direction and cooperates with the crucible cover to abut against the first fixing structure, and the second sleeve extends in the longitudinal direction and cooperates with the crucible bottom to abut against the second fixing structure.

[0024] As a further improvement of the present invention, the support portion is constructed with a plurality of fifth through holes, and the first sublimation zone is connected with the second sublimation zone through the fifth through holes.

[0025] As a further improvement of the present invention, a plurality of third through holes are formed on a side of the raw material crucible located in the first sublimation zone, and a plurality of fourth through holes are formed on a peripheral wall of a side of the raw material crucible located in the second sublimation zone.

[0026] Compared with the prior art, the present invention has the following beneficial effects:

[0027] The growth device provided by the present invention comprises: a crucible, a raw material crucible assembly arranged in the middle of the crucible, and a first fixed structure and a second fixed structure respectively arranged on the upper and lower sides of the raw material crucible assembly in the longitudinal direction; the raw material crucible assembly divides the inner cavity of the crucible into a first sublimation zone and a second sublimation zone arranged in the longitudinal direction and interconnected; the raw material crucible assembly comprises a raw material crucible, and the raw material crucible is used to hold aluminum nitride raw material; the first fixed structure is used to fix the first seed crystal, and the growth surface of the first seed crystal is exposed to the first sublimation zone; the second fixed structure is used to fix the second seed crystal, and the growth surface of the second seed crystal is exposed to the second sublimation zone. Under high temperature environment, the aluminum nitride raw material in the raw material crucible undergoes sublimation reaction to produce gaseous substances, and the gaseous substances diffuse from the raw material crucible to the first sublimation zone and the second sublimation zone at the same time, and the gaseous substances are deposited on the growth surfaces of the first seed crystal and the second seed crystal, and crystal growth is achieved through homoepitaxial growth, thereby achieving the synchronous growth of two aluminum nitride ingots in a single furnace, improving production efficiency and reducing energy consumption. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 The overall schematic diagram of the aluminum nitride growth device disclosed in the present invention, wherein a first guide structure is constructed inside the first fixed structure, and a second guide structure is constructed inside the second fixed structure;

[0029] Figure 2 is an overall schematic diagram of an aluminum nitride growth device in another embodiment, wherein a first guide structure is constructed inside the first fixed structure, and a second flow guide cover is arranged between the raw material crucible and the second fixed structure;

[0030] Figure 3 is an overall schematic diagram of an aluminum nitride growth device in another embodiment, wherein a first flow guide cover is arranged between the raw material crucible and the first fixed structure, and a second guide structure is constructed inside the second fixed structure;

[0031] Figure 4 is an overall schematic diagram of an aluminum nitride growth device in another embodiment, wherein a first flow guide cover is arranged between the raw material crucible and the first fixed structure, and a second flow guide cover is arranged between the raw material crucible and the second fixed structure;

[0032] Figure 5 It is a partial schematic diagram of the aluminum nitride growth device disclosed in the present invention, wherein a second flow guide cover is arranged between the raw material crucible and the second fixed structure. DETAILED DESCRIPTION

[0033] The present invention is described in detail below in conjunction with the various embodiments shown in the accompanying drawings, but it should be noted that these embodiments are not limitations of the present invention, and any equivalent transformations or substitutions in functions, methods, or structures made by ordinary technicians in the field based on these embodiments are all within the scope of protection of the present invention.

[0034] The drawings in the present invention are not drawn strictly according to the actual scale, and the specific size of each structure can be determined according to actual needs. The drawings described in the present invention are only schematic diagrams of the structures.

[0035] Ginseng Figure 1 As shown, Figure 1 The overall schematic diagram of the aluminum nitride growth device disclosed in the present invention, in this embodiment, the aluminum nitride growth device 100 includes: a crucible 10, a raw material crucible assembly (not shown) disposed in the middle of the crucible 10, and a longitudinal direction (i.e. Figure 1 The first fixing structure 31 and the second fixing structure 32 are respectively arranged on the upper and lower sides of the raw material crucible assembly (in the direction indicated by the X-axis).

[0036] The crucible 10 is made of pure tungsten. The raw material crucible assembly divides the inner cavity of the crucible 10 into a first sublimation zone 101 and a second sublimation zone 102 arranged longitudinally and interconnected; the raw material crucible assembly includes a raw material crucible 20, which is used to hold aluminum nitride raw materials. The first fixing structure 31 is used to fix the first seed crystal 201 and expose the growth surface of the first seed crystal 201 to the first sublimation zone 101, and the second fixing structure 32 is used to fix the second seed crystal 202 and expose the growth surface of the second seed crystal 202 to the second sublimation zone 102.

[0037] The raw material crucible 20 contains high-purity aluminum nitride raw materials, and the aluminum nitride raw materials undergo sublimation reaction under high temperature (2000-2300° C.) to generate gas phase substances (i.e., Al vapor and N 2 Gas), the gaseous material diffuses from the raw material crucible 20 to the first sublimation zone 101 and the second sublimation zone 102 at the same time. Since the first sublimation zone 101 and the second sublimation zone 102 are respectively provided with the first seed crystal 201 and the second seed crystal 202, the gaseous material can be transmitted to the first seed crystal 201 and the second seed crystal 202 respectively, so that the gaseous material is deposited on the growth surface of the first seed crystal 201 and the growth surface of the second seed crystal 202, and crystal growth is achieved through homoepitaxial growth, thereby realizing the synchronous growth of two aluminum nitride ingots in a single furnace.

[0038] The aluminum nitride growth device 100 disclosed in the present invention provides a closed growth environment for the first seed crystal 201 and the second seed crystal 202 through the crucible 10 to maintain the high temperature and high pressure conditions required for physical gas phase transmission. The raw material crucible 20 is arranged in the middle of the crucible 10, so that the first seed crystal 201 and the second seed crystal 202 are at an equal distance from the raw material crucible 20, so that the gas phase material can diffuse upward and downward uniformly, and the first seed crystal 201 and the second seed crystal 202 are supplied for growth at the same time, so as to ensure the consistency of the growth rate and quality of the first seed crystal 201 and the second seed crystal 202. And through the bidirectional diffusion of the gas phase material, the utilization rate of the aluminum nitride raw material can be improved. The edges of the first seed crystal 201 and the second seed crystal 202 are fixed by the first fixing structure 31 and the second fixing structure 32 respectively, so as to prevent the first seed crystal 201 and the second seed crystal 202 from loosening or shifting at high temperature, and to make the growth surfaces of the first seed crystal 201 and the second seed crystal 202 completely exposed to the corresponding first sublimation zone 101 and the second sublimation zone 102, so that the gas phase material can evenly cover the growth surfaces of the first seed crystal 201 and the second seed crystal 202, and ensure the flat growth of the crystal. The first sublimation zone 101 and the second sublimation zone 102 are connected to each other, so that the pressure of the gas phase material in the first sublimation zone 101 and the second sublimation zone 102 is automatically balanced, and the gas phase material is prevented from being biased due to the pressure difference.

[0039] The aluminum nitride growth device 100 disclosed in the present invention can simultaneously grow two aluminum nitride ingots in a single furnace. The two aluminum nitride ingots share the same heat field, fully utilize gas phase substances, and share energy consumption. Compared with traditional ingot growth devices, production efficiency is improved and energy consumption is reduced.

[0040] It should be noted that, in the aluminum nitride growth device 100 disclosed in the present invention, two independent aluminum nitride ingots grown synchronously complete single crystal epitaxy in their respective growth spaces, there is no lattice continuity between the two aluminum nitride ingots, and each meets the single crystal quality standard.

[0041] In some examples, reference Figure 1 As shown, the first fixed structure 31 is constructed with a first guiding structure 311 for guiding the gaseous substances generated by the sublimation of the aluminum nitride raw material in the raw material crucible 20 to the growth surface of the first seed crystal 201 in the first sublimation zone 101; the second fixed structure 32 is constructed with a second guiding structure 321 for guiding the gaseous substances generated by the sublimation of the aluminum nitride raw material in the raw material crucible 20 to the growth surface of the second seed crystal 202 in the second sublimation zone 102.

[0042] Under high temperature environment, the gas phase material diffuses from the raw material crucible 20 to the first sublimation area 101 and the second sublimation area 102 at the same time, and the gas phase material in the first sublimation area 101 is guided by the first guide structure 311 to converge and diffuse along the first sublimation area 101. Figure 1The gas phase substances in the second sublimation zone 102 are guided to converge and move along the growth surface of the first seed crystal 201 in the direction indicated by the middle arrow A11. Figure 1 The gas phase material is transported to the growth surface of the second seed crystal 202 in the direction indicated by the middle arrow A21, so that the gas phase material evenly covers the growth surfaces of the first seed crystal 201 and the second seed crystal 202, avoiding the local growth of the growth surfaces of the first seed crystal 201 and the second seed crystal 202 being too fast or too slow, and ensuring that the growth rates of the first seed crystal 201 and the second seed crystal 202 are basically consistent, thereby ensuring the quality and efficiency of the synchronous growth of the twin crystals.

[0043] In some examples, the first fixed structure 31 and the second fixed structure 32 are configured as hollow cylindrical structures so that the gas phase material can be transported along the inside of the cylindrical structure to the growth surface of the first seed crystal 201 and the second seed crystal 202. The middle part of the first fixed structure 31 is configured with a first slot 312 for holding the first seed crystal 201, and the middle part of the second fixed structure 32 is configured with a second slot 322 for holding the second seed crystal 202. The first slot 312 and the second slot 322 are used to fix the first seed crystal 201 and the second seed crystal 202 respectively, ensuring that the first seed crystal 201 and the second seed crystal 202 can maintain stable positioning in a high temperature environment, and avoiding the first seed crystal 201 and the second seed crystal 202 from shifting during the growth process.

[0044] In other examples, Figure 2 As shown, a first guide structure 311 is constructed inside the first fixed structure 31 to guide the gaseous substances generated by the sublimation of the aluminum nitride raw material in the raw material crucible 20 to the growth surface of the first seed crystal 201 in the first sublimation zone 101; the aluminum nitride growth device 100 also includes: a second flow guide cover 52 longitudinally arranged between the raw material crucible 20 and the second fixed structure 32, and the second flow guide cover 52 is used to guide the gaseous substances generated by the sublimation of the aluminum nitride raw material in the raw material crucible 20 to the growth surface of the second seed crystal 202 in the second sublimation zone 102.

[0045] The second guide cover 52 is disposed in the second sublimation zone 102 and together with the raw material crucible 20, forms a second guide area 522. Under high temperature conditions, the gas phase material diffuses from the raw material crucible 20 to the first sublimation zone 101 and the second guide area 522 at the same time. The gas phase material in the first sublimation zone 101 is guided to converge and diffuse along the first guide structure 311. Figure 2 The gas phase material in the second guide area 522 is transported to the growth surface of the first seed crystal 201 in the direction indicated by the middle arrow A11, and the gas phase material in the second guide area 522 is guided along the second guide area 522 by the second guide cover 52. Figure 2The gas-phase material diffuses toward the second sublimation zone 102 in the direction indicated by the middle arrow A21, and at the same time, the gas-phase material is transported to the growth surface of the second seed crystal 202, so that the gas-phase material evenly covers the growth surfaces of the first seed crystal 201 and the second seed crystal 202. Since the space of the second guide area 522 is more compact, the movement path of the gas-phase material in the second guide area 522 to the growth surface of the second seed crystal 202 is shorter, thereby reducing the diffusion loss of the gas-phase material during the transportation process or the scattering caused by collision, and suppressing the volatilization rate of the gas-phase material.

[0046] In another example, Figure 3 As shown, the aluminum nitride growth device 100 also includes: a first flow guide hood 51 longitudinally arranged between the raw material crucible 20 and the first fixed structure 31, the first flow guide hood 51 is used to guide the gaseous substances generated by the sublimation of the aluminum nitride raw material in the raw material crucible 20 to the growth surface of the first seed crystal 201 in the first sublimation zone 101; the second fixed structure 32 is constructed with a second guide structure 321 inside to guide the gaseous substances generated by the sublimation of the aluminum nitride raw material in the raw material crucible 20 to the growth surface of the second seed crystal 202 in the second sublimation zone 102.

[0047] The first guide cover 51 is disposed in the first sublimation zone 101 and together with the raw material crucible 20, forms a first guide area 512. Under high temperature conditions, the gaseous material diffuses from the raw material crucible 20 to the first guide area 512 and the second sublimation zone 102 at the same time. The gaseous material in the first guide area 512 is guided by the first guide cover 51 to diffuse along the first sublimation zone 101. Figure 3 The gas phase material in the second sublimation zone 102 is guided by the second guiding structure 321 to converge and move along the first sublimation zone 101. Figure 3 The gas phase material is transported to the growth surface of the second seed crystal 202 in the direction indicated by the middle arrow A21, so that the gas phase material evenly covers the growth surfaces of the first seed crystal 201 and the second seed crystal 202. Since the space of the first guide area 512 is more compact, the movement path of the gas phase material in the first guide area 512 to the growth surface of the first seed crystal 201 is shorter, thereby reducing the diffusion loss of the gas phase material during the transportation process or the scattering caused by collision, and suppressing the volatilization rate of the gas phase material.

[0048] In some examples, reference Figures 1 to 3 As shown, the inner diameter of the first guide structure 311 decreases from the bottom of the first fixing structure 31 to one side of the first slot 312 ; the inner diameter of the second guide structure 321 decreases from the bottom of the second fixing structure 32 to one side of the second slot 322 .

[0049] The first guide structure 311 and the second guide structure 321 have gradually tapered inner diameters, so that the gaseous substances diffused into the first sublimation zone 101 converge toward the first guide structure 311, so that the gaseous substances can be concentrated and uniformly dispersed along the first sublimation zone 101. Figure 1 and Figure 2 The gas phase material is transported to the growth surface of the first seed crystal 201 in the direction indicated by the middle arrow A11, and the gas phase material diffused to the second sublimation zone 102 converges toward the second guide structure 321, so that the gas phase material can be concentrated and uniformly along the Figure 1 and Figure 3 The gas phase material is transported to the growth surface of the second seed crystal 202 in the direction indicated by the middle arrow A21, so that the supply of gas phase material in each area of ​​the growth surface of the first seed crystal 201 and the second seed crystal 202 is consistent, avoiding the local growth rate difference caused by uneven distribution of gas phase material, and preventing defects such as step aggregation and micro cracks.

[0050] In other examples, Figure 4 As shown, the aluminum nitride growth device 100 also includes: a first flow guide cover 51 longitudinally arranged between the raw material crucible 20 and the first fixed structure 31, and a second flow guide cover 52 longitudinally arranged between the raw material crucible 20 and the second fixed structure 32; the first flow guide cover 51 is used to guide the gaseous substances generated by the sublimation of the aluminum nitride raw material in the raw material crucible 20 to the growth surface of the first seed crystal 201 in the first sublimation zone 101, and the second flow guide cover 52 is used to guide the gaseous substances generated by the sublimation of the aluminum nitride raw material in the raw material crucible 20 to the growth surface of the second seed crystal 202 in the second sublimation zone 102.

[0051] The first flow guide 51 is disposed in the first sublimation zone 101 and together with the raw material crucible 20 constitutes a first guide area 512, and the second flow guide 52 is disposed in the second sublimation zone 102 and together with the raw material crucible 20 constitutes a second guide area 522. Under high temperature conditions, the gas phase material diffuses from the raw material crucible 20 to the first guide area 512 and the second guide area 522 at the same time. The gas phase material in the first guide area 512 is guided by the first flow guide 51 to diffuse along the first sublimation zone 101 and the raw material crucible 20. Figure 4 The gas phase material is diffused toward the first sublimation zone 101 in the direction indicated by the middle arrow A11, and at the same time, the gas phase material is transported to the growth surface of the first seed crystal 201, and the gas phase material in the second guide area 522 is guided along the second guide cover 52. Figure 4The gas phase material diffuses toward the second sublimation zone 102 in the direction indicated by the middle arrow A21, and at the same time, the gas phase material is transported to the growth surface of the second seed crystal 202, so that the gas phase material uniformly covers the growth surfaces of the first seed crystal 201 and the second seed crystal 202, avoids the local growth of the growth surfaces of the first seed crystal 201 and the second seed crystal 202 being too fast or too slow, and ensures that the growth rates of the first seed crystal 201 and the second seed crystal 202 are basically the same, ensures the quality and efficiency of the synchronous growth of the twin crystals, and makes the gas phase material supply of each region of the growth surface of the first seed crystal 201 and the second seed crystal 202 consistent, avoids the difference in local growth rate caused by uneven distribution of the gas phase material, and prevents defects such as step aggregation and micro cracks. Since the space of the first guide area 512 and the second guide area 522 is more compact, the movement path of the gas phase material in the first guide area 512 and the second guide area 522 to be transported to the growth surfaces of the first seed crystal 201 and the second seed crystal 202 is shorter, thereby reducing the diffusion loss of the gas phase material during the transportation process or the scattering caused by collision, and suppressing the volatilization rate of the gas phase material.

[0052] In some examples, reference Figures 2 to 4 As shown, the inner diameter of the first flow guide cover 51 decreases from the raw material crucible 20 to the side of the first fixed structure 31, and a plurality of first through holes 511 are formed on the side of the first flow guide cover 51 close to the growth surface of the first seed crystal 201; the inner diameter of the second flow guide cover 52 decreases from the raw material crucible 20 to the side of the second fixed structure 32, and a plurality of second through holes 521 are formed on the side of the second flow guide cover 52 close to the growth surface of the second seed crystal 202. The first flow guide cover 51 is spaced a certain distance from the first seed crystal 201 in the longitudinal direction, and the first through holes 511 correspond to the growth surface of the first seed crystal 201 in the longitudinal direction. The second flow guide cover 52 is spaced a certain distance from the second seed crystal 202 in the longitudinal direction, and the second through holes 521 correspond to the growth surface of the second seed crystal 202 in the longitudinal direction.

[0053] The first guide cover 51 has a tapered inner diameter, so that the gaseous substances diffused into the first guide area 512 are gathered toward the side of the first guide cover 51 close to the growth surface of the first seed crystal 201, and the first through hole 511 corresponds to the growth surface of the first seed crystal 201 in the longitudinal direction, so that the gaseous substances in the first guide area 512 can be concentrated and uniformly distributed along the first through hole 511. Figure 3 and Figure 4 The gas-phase material is transported to the growth surface of the first seed crystal 201 in the direction indicated by the middle arrow A11, and diffuses to the first sublimation zone 101 at the same time. In the process of the gas-phase material being transported to the growth surface of the first seed crystal 201 through the first through hole 511, the gas-phase material is more easily constrained in the direction pointing to the growth surface of the first seed crystal 201, thereby reducing lateral escape, improving the effective transmission rate, and making the gas-phase material more evenly deposited on the growth surface of the first seed crystal 201.

[0054] The second guide cover 52 has a tapered inner diameter, so that the gaseous substances diffused into the second guide area 522 are gathered toward the side of the second guide cover 52 close to the growth surface of the second seed crystal 202, and the second through hole 521 corresponds to the growth surface of the second seed crystal 202 in the longitudinal direction, so that the gaseous substances in the second guide area 522 can be concentrated and uniformly distributed along the second through hole 521. Figure 2 and Figure 4 The gas-phase material is transported to the growth surface of the second seed crystal 202 in the direction indicated by the middle arrow A21, and diffuses to the second sublimation zone 102 at the same time. In the process of the gas-phase material being transported to the growth surface of the second seed crystal 202 through the second through hole 521, the gas-phase material is more easily constrained in the direction pointing to the growth surface of the second seed crystal 202, thereby reducing lateral escape, improving the effective transmission rate, and making the gas-phase material more evenly deposited on the growth surface of the second seed crystal 202.

[0055] In some examples, reference Figures 1 to 4 As shown, the crucible 10 includes: a crucible bottom 11, a crucible cover 12, and a crucible barrel 13 with openings at both ends and adjustable height. The bottom of the crucible barrel 13 is installed on the crucible bottom 11, and the crucible cover 12 is installed on the top opening of the crucible barrel 13. The aluminum nitride growth device 100 also includes: a first sleeve 41 and a second sleeve 42 that are continuously arranged in the longitudinal direction and attached to the inner wall of the crucible 10; the first sleeve 41 extends in the longitudinal direction to the installation gap between the crucible cover 12 and the crucible barrel 13, and the second sleeve 42 extends in the longitudinal direction to the installation gap between the crucible barrel 13 and the crucible bottom 11. By adjusting the height of the crucible barrel 13, the internal volume of the crucible 10 can be adjusted, so as to flexibly adapt to the raw material crucible 20 with different raw material loading amounts. The first sleeve 41 covers the installation gap between the crucible cover 12 and the crucible barrel 13, and the second sleeve 42 covers the installation gap between the crucible barrel 13 and the crucible bottom 11, so as to enhance the sealing of the crucible 10, prevent leakage of gaseous substances, reduce the contamination of the furnace (not shown) outside the crucible 10 by gaseous substances, and reduce the heat loss inside the crucible 10, thereby ensuring that the heat is evenly distributed inside the entire crucible 10.

[0056] In some examples, reference Figures 1 to 4 As shown, the raw material crucible assembly also includes a support portion 23 that protrudes outward in the circumferential direction and extends between the first sleeve 41 and the second sleeve 42. The first sleeve 41 and the second sleeve 42 longitudinally abut the outer peripheral edge of the support portion 23; the first sleeve 41 extends longitudinally and cooperates with the crucible cover 12 to abut the first fixed structure 31, and the second sleeve 42 extends longitudinally and cooperates with the crucible bottom 11 to abut the second fixed structure 32.

[0057] The first sleeve 41 and the second sleeve 42 are used to longitudinally abut the outer periphery of the support portion 23 to fix the position of the raw material crucible 20 in the crucible 10, prevent the raw material crucible 20 from being offset due to gravity or thermal stress, and ensure the stability of the position of the raw material crucible 20 in a high temperature environment. The first sleeve 41 and the crucible cover 12 are used to abut the first fixing structure 31, and the second sleeve 42 and the crucible bottom 11 are used to abut the second fixing structure 32 to stabilize the positions of the first seed crystal 201 and the second seed crystal 202, and ensure the stability of the positions of the first seed crystal 201 and the second seed crystal 202 in a high temperature environment. The support portion 23 is constructed with a plurality of fifth through holes 231, and the first sublimation zone 101 and the second sublimation zone 102 are connected through the fifth through holes 231, so that the pressure of the gas phase substances in the first sublimation zone 101 and the second sublimation zone 102 is automatically balanced to avoid the gas phase substances from being biased due to the pressure difference.

[0058] In some examples, reference Figures 1 to 4 As shown, the raw material crucible 20 is composed of a lower crucible body 22 and an upper crucible body 21, the upper crucible body 21 covers the lower crucible body 22, and the support portion 23 is formed on the lower crucible body 22. The raw material crucible 20 adopts a split structure, and the upper crucible body 21 can detachably cover the lower crucible body 22 to facilitate raw material loading and cleaning and maintenance, and the split joint surface of the upper crucible body 21 and the lower crucible body 22 adopts a stepped sealing structure to reduce heat flow loss.

[0059] In some examples, reference Figures 1 to 4 As shown, the raw material crucible 20 is formed on one side of the first sublimation zone 101 and has a plurality of third through holes 211; the raw material crucible 20 is formed on one side of the second sublimation zone 102 and has a plurality of fourth through holes 221, and the fourth through holes 221 are close to the bottom of the raw material crucible 20. Under high temperature, the aluminum nitride raw material in the raw material crucible 20 undergoes a sublimation reaction, and the gas phase material passes through the third through holes 211 along the Figure 1 The liquid flows in the direction indicated by the middle arrow A1 to the first sublimation area 101, and passes through the fourth through hole 221 along the Figure 1 The upper crucible 21 has a plurality of third through holes 211 formed on the top and / or the peripheral wall thereof, which is not limited in the present invention. The gas phase material passes through the fourth through holes 221 along the peripheral wall of the lower crucible 22. Figure 1 The aluminum nitride raw material diffuses laterally to the second sublimation zone 102 in the direction indicated by the middle arrow A2, preventing the aluminum nitride raw material from falling onto the second seed crystal 202 and contaminating the growth surface of the second seed crystal 202.

[0060] In some examples, reference Figure 5 As shown, Figure 5It is a partial schematic diagram of the aluminum nitride growth device 100 disclosed in the present invention, wherein a second flow guide cover 52 is disposed longitudinally between the raw material crucible 20 and the second fixed structure 32. Exemplarily, the diameter L1 of the raw material crucible 20 is 80 mm, the inner diameter L2 of the crucible 10 is 150 mm, the diameter L3 of the second seed crystal 202 is 50 mm to 100 mm, the vertical distance H1 between the top of the second flow guide cover 52 and the bottom of the support portion 23 is 38.65 mm, the vertical distance H2 between the bottom of the second flow guide cover 52 and the growth surface of the second seed crystal 202 is 50 mm, and the height H3 of the second flow guide cover 52 is 56.5 mm.

[0061] The peripheral wall 520 of the second flow guide hood 52 forms an angle α with the horizontal plane, and the angle α is preferably set to 60°. In the low-pressure environment inside the crucible 10, the mean free path of gas molecules is longer, and the motion trajectory is closer to a straight line, and the collision frequency between gas molecules is low. By adopting a 60° inclination angle, the gas phase material in the second guide area 522 can be more easily moved along the inclined direction of the peripheral wall 520, so as to reduce the number of collisions between gas molecules and the inner wall surface of the peripheral wall 520, and increase the probability of gas molecules directly reaching the growth surface of the second seed crystal 202. In addition, the 60° inclination angle can effectively suppress the generation of eddy currents or turbulence, maintain a stable laminar flow state, and ensure that the gas phase material flows in an orderly and efficient directional manner.

[0062] In some examples, the first flow guide hood 51 is similar to the second flow guide hood 52, and the angle formed by its peripheral wall and the horizontal plane is also preferably 60°. Since the structures, functions and technical effects of the first flow guide hood 51 and the second flow guide hood 52 are completely symmetrical and equivalent, their specific implementation methods can refer to the description of the second flow guide hood 52 above, and will not be repeated here. The first flow guide hood 51 and the second flow guide hood 52 form a synergistic effect, jointly adapting to the gas phase transmission characteristics of the low-pressure environment inside the crucible 10, and through flow field optimization and laminar flow control, the high efficiency and quality consistency of the growth of the first seed crystal 201 and the second seed crystal 202 are achieved.

[0063] In summary, the growth device provided by the present invention includes: a crucible, a raw material crucible assembly arranged in the middle of the crucible, and a first fixed structure and a second fixed structure respectively arranged on the upper and lower sides of the raw material crucible assembly in the longitudinal direction; the raw material crucible assembly divides the inner cavity of the crucible into a first sublimation zone and a second sublimation zone arranged in the longitudinal direction and interconnected; the raw material crucible assembly includes a raw material crucible, and the raw material crucible is used to hold aluminum nitride raw material; the first fixed structure is used to fix the first seed crystal, and the growth surface of the first seed crystal is exposed to the first sublimation zone; the second fixed structure is used to fix the second seed crystal, and the growth surface of the second seed crystal is exposed to the second sublimation zone. Under high temperature environment, the aluminum nitride raw material in the raw material crucible undergoes a sublimation reaction to produce gaseous substances, and the gaseous substances diffuse from the raw material crucible to the first sublimation zone and the second sublimation zone at the same time, and the gaseous substances are deposited on the growth surfaces of the first seed crystal and the second seed crystal, and crystal growth is achieved through homoepitaxial growth, thereby achieving the synchronous growth of two aluminum nitride ingots in a single furnace, improving production efficiency and reducing energy consumption. Moreover, by setting the first guide cover and the second guide cover, the gas phase material can be more easily guided directly to the growth surfaces of the two seed crystals, reducing lateral escape, improving the effective transmission rate, and being able to be more evenly transmitted to the growth surface of the seed crystal helps to improve the quality of the aluminum nitride ingot.

[0064] The series of detailed descriptions listed above are only specific descriptions of feasible implementation methods of the present invention. They are not intended to limit the scope of protection of the present invention. Any equivalent implementation methods or changes that do not deviate from the technical spirit of the present invention should be included in the scope of protection of the present invention.

[0065] It will be apparent to those skilled in the art that the invention is not limited to the details of the exemplary embodiments described above and that the invention can be implemented in other specific forms without departing from the spirit or essential features of the invention. Therefore, the embodiments should be considered exemplary and non-limiting in all respects, and the scope of the invention is defined by the appended claims rather than the foregoing description, and it is intended that all variations falling within the meaning and scope of the equivalent elements of the claims be included in the invention. Any reference numeral in a claim should not be considered as limiting the claim to which it relates.

[0066] In addition, it should be understood that although the present specification is described according to implementation modes, not every implementation mode contains only one independent technical solution. This description of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment may also be appropriately combined to form other implementation modes that can be understood by those skilled in the art.

Claims

1. An aluminum nitride growth device, characterized in that: include: A crucible, a raw material crucible assembly disposed in the middle of the crucible, and a first fixing structure and a second fixing structure respectively disposed at upper and lower sides of the raw material crucible assembly in the longitudinal direction; Wherein, the raw material crucible assembly divides the inner cavity of the crucible into a first sublimation zone and a second sublimation zone which are arranged in the longitudinal direction and are interconnected; The raw material crucible assembly comprises a raw material crucible, and the raw material crucible is used to hold aluminum nitride raw materials; The first fixing structure is used to fix the first seed crystal and expose the growth surface of the first seed crystal to the first sublimation zone; The second fixing structure is used to fix the second seed crystal and expose the growth surface of the second seed crystal to the second sublimation zone.

2. The aluminum nitride growth device according to claim 1, characterized in that: A first guiding structure is constructed inside the first fixed structure for guiding the gas phase material generated by the sublimation of the aluminum nitride raw material in the raw material crucible to the growth surface of the first seed crystal in the first sublimation zone; A second guiding structure for guiding the gaseous substances generated by the sublimation of the aluminum nitride raw material in the raw material crucible to the growth surface of the second seed crystal in the second sublimation zone is constructed inside the second fixed structure.

3. The aluminum nitride growth device according to claim 1, characterized in that: The aluminum nitride growth device further includes: a first flow guide cover disposed longitudinally between the raw material crucible and the first fixed structure, and a second flow guide cover disposed longitudinally between the raw material crucible and the second fixed structure; The first flow guide cover is used to guide the gaseous substances generated by the sublimation of the aluminum nitride raw material in the raw material crucible to the growth surface of the first seed crystal in the first sublimation zone, and the second flow guide cover is used to guide the gaseous substances generated by the sublimation of the aluminum nitride raw material in the raw material crucible to the growth surface of the second seed crystal in the second sublimation zone.

4. The aluminum nitride growth device according to claim 1, characterized in that: A first guide structure is constructed inside the first fixed structure for guiding the gaseous substances generated by the sublimation of the aluminum nitride raw material in the raw material crucible to the growth surface of the first seed crystal in the first sublimation zone; the aluminum nitride growth device also includes: a second flow guide cover arranged between the raw material crucible and the second fixed structure in the longitudinal direction, the second flow guide cover is used to guide the gaseous substances generated by the sublimation of the aluminum nitride raw material in the raw material crucible to the growth surface of the second seed crystal in the second sublimation zone; Alternatively, the aluminum nitride growth device also includes: a first flow guide cover longitudinally arranged between the raw material crucible and the first fixed structure, the first flow guide cover is used to guide the gaseous substances generated by the sublimation of the aluminum nitride raw material in the raw material crucible to the growth surface of the first seed crystal in the first sublimation zone; and a second guide structure is constructed inside the second fixed structure for guiding the gaseous substances generated by the sublimation of the aluminum nitride raw material in the raw material crucible to the growth surface of the second seed crystal in the second sublimation zone.

5. The aluminum nitride growth device according to claim 2 or 4, characterized in that: A first clamping groove for holding the first seed crystal is configured in the middle of the first fixing structure, and the inner diameter of the first guiding structure decreases from the bottom of the first fixing structure to one side of the first clamping groove; A second clamping groove for holding the second seed crystal is constructed in the middle of the second fixing structure, and the inner diameter of the second guide structure decreases from the bottom of the second fixing structure to one side of the second clamping groove.

6. The aluminum nitride growth device according to claim 3 or 4, characterized in that: The inner diameter of the first flow guide cover decreases gradually from the raw material crucible to one side of the first fixed structure, and a plurality of first through holes are formed on one side of the first flow guide cover close to the growth surface of the first seed crystal; The inner diameter of the second flow guide cover decreases gradually from the raw material crucible to one side of the second fixed structure, and a plurality of second through holes are formed on one side of the second flow guide cover close to the growth surface of the second seed crystal.

7. The aluminum nitride growth device according to claim 1, characterized in that: The crucible comprises: a crucible bottom, a crucible cover and a crucible barrel with openings at both ends and adjustable height, the bottom of the crucible barrel is installed on the crucible bottom, and the crucible cover is installed on the top opening of the crucible barrel; The aluminum nitride growth device also includes: a first sleeve and a second sleeve which are continuously arranged in the longitudinal direction and attached to the inner wall of the crucible; the first sleeve extends in the longitudinal direction to the installation gap between the crucible cover and the crucible barrel, and the second sleeve extends in the longitudinal direction to the installation gap between the crucible barrel and the crucible bottom.

8. The aluminum nitride growth device according to claim 7, characterized in that: The raw material crucible assembly further includes a support portion that protrudes outwardly in the circumferential direction and extends between the first sleeve and the second sleeve, and the first sleeve and the second sleeve abut against the outer circumference of the support portion in the longitudinal direction; The first sleeve extends in the longitudinal direction and cooperates with the crucible cover to abut against the first fixing structure, and the second sleeve extends in the longitudinal direction and cooperates with the crucible bottom to abut against the second fixing structure.

9. The aluminum nitride growth device according to claim 8, characterized in that: The support portion is constructed with a plurality of fifth through holes, and the first sublimation area is connected with the second sublimation area through the fifth through holes.

10. The aluminum nitride growth device according to claim 1, characterized in that: A plurality of third through holes are formed on a side of the raw material crucible located in the first sublimation zone, and a plurality of fourth through holes are formed on a peripheral wall of a side of the raw material crucible located in the second sublimation zone.

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