A silicon carbide crystal boat

Abstract

This utility model relates to a silicon carbide crystal boat, comprising two end plates arranged opposite each other, and a slotted bar disposed between the end plates. Each end plate is composed of region A, region B, and region C. Region A has two uniformly spaced A-type expansion joints. One end plate has a mis-detection hole at the center of the lower edge of region C, along which a B-type expansion joint is formed. The other end plate has a C-type expansion joint starting from the lower edge of region C. The lengths of the A-type, B-type, and C-type expansion joints are all 1 / 4 to 1 / 3 of the height of the end plate, and their widths are all 2 to 4 mm. The length of the A-type expansion joint is less than the length of the B-type expansion joint, and the length of the B-type expansion joint is less than the length of the C-type expansion joint. Through the dual optimization of the topology and geometry of the end plate partitioned expansion joints and the slotted bar, thermal stress reduction is achieved, providing a core guarantee for the long lifespan and low defect rate operation of the silicon carbide crystal boat in high-temperature semiconductor processes.

Description

Technical Field

[0001] This utility model relates to the field of semiconductor technology, specifically to a silicon carbide crystal boat. Background Technology

[0002] Silicon carbide boats are high-end support tools designed specifically for precision manufacturing fields such as semiconductors, photovoltaics, and LEDs. Made from high-purity silicon carbide, they are used to stably support silicon wafers, phantoms, or other substrates during high-temperature and corrosive processes. Their core function is to meet the demands of stringent processes such as chemical vapor deposition, diffusion, and annealing. However, existing silicon carbide boats have relatively high manufacturing costs and often fracture during rapid heating and cooling due to uneven local stress release. Therefore, they negatively impact production processes, product quality, equipment safety, and economic efficiency, limiting their application. Summary of the Invention

[0003] In view of the shortcomings of the existing technology, this utility model proposes a silicon carbide crystal boat with long life and low defects.

[0004] This utility model discloses a silicon carbide crystal boat, comprising two end plates arranged opposite to each other, and a grooved bar disposed between the end plates; the end plates are composed of region A, region B and region C, and region A has two A-type expansion joints evenly distributed thereon; one end plate has a foolproof hole at the middle position of the lower edge of region C, and a B-type expansion joint is formed along the foolproof hole; the other end plate has a C-type expansion joint starting from the lower edge of region C.

[0005] The lengths of the type A, type B, and type C expansion joints are all 1 / 4 to 1 / 3 of the height of the end plate, and the widths are all 2 to 4 mm. The length of the type A expansion joint is less than the length of the type B expansion joint, and the length of the type B expansion joint is less than the length of the type C expansion joint.

[0006] Furthermore, the side of the A-type expansion joint of the silicon carbide crystal boat of this utility model away from the B area intersects with the edge of the end plate, and the intersection is an arc-shaped opening.

[0007] Furthermore, the silicon carbide crystal boat of this utility model has 5 slot bars, with two slot bars symmetrically arranged on the edge of the end plate near the A region, one slot bar on the edge of the end plate corresponding to the B region, and two slot bars symmetrically arranged on the edge of the end plate near the C region.

[0008] Furthermore, the cross-section of the groove bar of the silicon carbide crystal boat described in this utility model is teardrop-shaped or circular.

[0009] Furthermore, the side of the groove bar of the silicon carbide crystal boat facing away from the center of the end plate is arc-shaped, and the side of the groove bar facing the center of the end plate has multiple slots arranged side by side. The bottom of the slots is arc-shaped, and the slots are toothed.

[0010] The slot is composed of an arc-shaped bottom surface and two inclined surfaces. The angle between the inclined surfaces and the horizontal plane is 3~5°, and the width of the slot opening is greater than the width of its bottom. The depth of the slot is 1 / 5~1 / 3 of the longest dimension on the cross-section of the slot bar. The thickness of the end of the slot tooth is d, and the width of the slot opening is D, satisfying d=(0.5~0.8)D.

[0011] Furthermore, the outer side of the end plate of the silicon carbide crystal boat described in this utility model is also provided with a handle, which is a limiting structure for placing the silicon carbide crystal boat on the carrier.

[0012] The beneficial effects of this utility model are:

[0013] This invention relates to a silicon carbide crystal boat, a complex structural component formed in one piece and then slotted. On one hand, by employing a zoned design (zones A, B, and C) and configuring differentiated expansion joints, targeted stress release is achieved for the thermal expansion differences in different areas of the end plate, significantly reducing the thermal stress concentration coefficient during high-temperature processes. The A-type expansion joint uses a rounded opening design at its intersection with the end plate edge, effectively eliminating right-angle stress concentration points and significantly improving the fatigue resistance of the end plate under repeated thermal cycling. On the other hand, the expansion joint width is strictly controlled (2~4mm), minimizing structural strength loss while ensuring process gas flow, ensuring the end plate maintains good bending strength under high-temperature conditions. Furthermore, the coaxial layout of the anti-misalignment hole in zone C and the B-type expansion joint not only provides mechanical anti-misalignment functionality but also guides stress diffusion along the periphery of the hole, significantly reducing the risk of cracking at the corners of traditional rectangular end plates. Overall, this greatly improves the structural reliability and service life of the crystal boat under harsh thermal environments.

[0014] This invention also utilizes a non-uniform distribution of slot bars (two symmetrically distributed in areas A and C, and one in the center of area B) to form an optimized topology of "three-point main support + four-point auxiliary positioning." Combined with the precise geometric design of the slot bar cross-section (teardrop or circular) and the slot, this significantly improves the stability and process performance of wafer positioning. Designing the opposite sides of every two slot bars as an arc shape further enhances the wear resistance of the wafer boat, reducing surface wear during frequent use and cleaning, thereby ensuring the performance of the wafer boat and unaffected wafer placement. Attached Figure Description

[0015] Figure 1 This is a schematic diagram of the structure of the silicon carbide crystal boat described in this utility model;

[0016] Figure 2 This is a schematic diagram of the end plate of the present invention;

[0017] Figure 3 This is a partial structural schematic diagram of the grooved bar described in this utility model;

[0018] Figure 4 This is a cross-sectional view of the groove bar of the silicon carbide crystal boat described in Embodiment 1 of this utility model;

[0019] Among them: 1. End plate, 2. Handle, 3. Groove bar, 4. Slot, 5. Groove teeth, 100. Area A, 200. Area B, 300. Area C, 101. Type A expansion joint, 301. Anti-fool hole, 302. Type B expansion joint, 303. Type C expansion joint. Detailed Implementation

[0020] To make the objectives, technical solutions, and advantages of the specific embodiments of this utility model clearer, the technical solutions in the specific embodiments of this utility model will be clearly and completely described below. Where specific conditions are not specified in the specific embodiments, they shall be performed according to conventional conditions or conditions recommended by the manufacturer.

[0021] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art. The terminology used in the specification herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. The term "and / or" as used herein includes any and all combinations of one or more of the associated listed items. Example 1:

[0022] As shown in Figures 1-4, a silicon carbide crystal boat includes two end plates 1 arranged opposite each other, and a grooved bar 3 disposed between the end plates 1. The end plate 1 is composed of an A region 100, a B region 200, and a C region 300. The A region 100 has two A-type expansion joints 101 evenly distributed. An anti-fool hole 301 is provided at the middle position of the lower edge of the C region 300 of one end plate 1, and a B-type expansion joint 302 is provided along the anti-fool hole 301. The other end plate 1 has a C-type expansion joint 303 starting from the lower edge of the C region 300. The outer side of the end plate 1 of the silicon carbide crystal boat of this invention is also provided with a handle 2.

[0023] The lengths of the type A expansion joint 101, type B expansion joint 302, and type C expansion joint 303 are all 1 / 4 to 1 / 3 of the height of the end plate 1, and the widths are all 2 to 4 mm. The length of the type A expansion joint 101 is less than the length of the type B expansion joint 302, and the length of the type B expansion joint 302 is less than the length of the type C expansion joint 303.

[0024] In this embodiment 1, the side of the A-type expansion joint 101 away from the B area 200 intersects with the edge of the end plate 1, and the intersection is an arc-shaped opening.

[0025] The number of grooved rods 3 is 5. Two grooved rods 3 are symmetrically arranged on the edge of the end plate 1 near the edge of area A 100, one grooved rod 3 is arranged on the edge of the end plate 1 corresponding to area B 200, and two grooved rods 3 are symmetrically arranged on the edge of the end plate 1 near the edge of area C 300. The cross-section of the grooved rod 3 is teardrop-shaped or circular. The side of the grooved rod 3 facing away from the center of the end plate is arc-shaped, and multiple slots 4 are arranged side by side on the side of the grooved rod 3 facing the center of the end plate. The bottom of the slots 4 is arc-shaped, and there are teeth 5 between the slots 4.

[0026] The slot 4 consists of an arc-shaped bottom surface and two inclined surfaces. The angle between the inclined surfaces and the horizontal plane is 3-5°. The width of the slot opening is greater than the width of its bottom, and the inclined surfaces are flat planes without any protrusions. The depth of the slot 4 is 1 / 5 to 1 / 3 of the longest dimension on the cross-section of the slotted rod 3. The thickness of the end of the slot tooth is d, and the width of the slot opening is D, satisfying d = (0.5-0.8)D. In this embodiment 1, the angle between the inclined surfaces and the horizontal plane is 4°, the depth of the slot 4 is 5.3 mm, and the width D of the slot opening is 0.17 mm.

[0027] The silicon carbide crystal boat described in this utility model is a one-piece molded design. During use, the wafers are inserted one by one into the slot 4, and then the silicon carbide crystal boat is loaded into the boat support and slowly moved along the length direction of the boat support. The wafers are constrained by the arc-shaped bottom surface of the slot 4 in the direction of movement and will not move, thereby greatly improving the operation efficiency and safety.

[0028] The embodiments described above are some, but not all, embodiments of this utility model. The detailed description of the embodiments of this utility model is not intended to limit the scope of the claimed utility model, but merely to illustrate selected embodiments of the utility model. All other embodiments obtained by those skilled in the art based on the embodiments of this utility model without inventive effort are within the scope of protection of this utility model.

Claims

1. A silicon carbide boat, comprising two end plates (1) disposed opposite to each other, and a grooved bar (3) disposed between the end plates (1); characterized in that, The end plate (1) is composed of area A (100), area B (200) and area C (300). Area A (100) has two A-type expansion joints (101) evenly distributed. An anti-fool hole (301) is provided at the middle position of the lower edge of area C (300) of one end plate (1), and a B-type expansion joint (302) is provided along the anti-fool hole (301). The other end plate (1) has a C-type expansion joint (303) starting from the lower edge of area C (300). The lengths of the type A expansion joint (101), type B expansion joint (302), and type C expansion joint (303) are all 1 / 4 to 1 / 3 of the height of the end plate (1), and the widths are all 2 to 4 mm. The length of the type A expansion joint (101) is less than the length of the type B expansion joint (302), and the length of the type B expansion joint (302) is less than the length of the type C expansion joint (303).

2. The silicon carbide boat according to claim 1, characterized in that: The side of the type A expansion joint (101) away from the area B (200) intersects with the edge of the end plate (1), and the intersection is an arc-shaped opening.

3. The silicon carbide boat according to claim 1, characterized in that: The number of grooved bars (3) is 5. Two grooved bars (3) are symmetrically arranged on the edge of the end plate (1) near the A area (100). One grooved bar (3) is arranged on the edge of the end plate (1) corresponding to the B area (200). Two grooved bars (3) are symmetrically arranged on the edge of the end plate (1) near the C area (300).

4. The silicon carbide boat according to claim 1, characterized in that: The cross-section of the grooved rod (3) is teardrop-shaped or circular.

5. The silicon carbide boat according to claim 4, characterized in that: The side of the grooved bar (3) facing away from the center of the end plate is arc-shaped, and the side of the grooved bar (3) facing the center of the end plate has multiple slots (4) arranged side by side. The bottom of the slots (4) is arc-shaped, and the slots (4) are toothed (5). The slot (4) consists of an arc-shaped bottom surface and two inclined surfaces. The angle between the inclined surfaces and the horizontal plane is 3~5°, and the width of the slot (4) is greater than the width of its bottom. The depth of the slot (4) is 1 / 5~1 / 3 of the longest dimension on the cross-section of the slot bar (3). The thickness of the end of the slot tooth (5) is d. The width of the slot (4) is D, and d=(0.5~0.8)D is satisfied.

6. The silicon carbide boat according to claim 1, characterized in that: The end plate (1) is also provided with a handle (2) on its outer side.

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