Silicon carbide substrate wafer annealing fixture

Abstract

This utility model discloses a silicon carbide substrate wafer annealing fixture, belonging to the field of semiconductor manufacturing equipment technology. The annealing barrel of this silicon carbide substrate wafer annealing fixture is formed by the joining of two symmetrically arranged annealing half-barrels. The side walls connecting the two annealing half-barrels are respectively provided with mutually cooperating protrusions and mating grooves for positioning and fitting, thus enclosing the two annealing half-barrels together to form a closed annealing cavity, the interior of which has a groove for supporting the silicon carbide wafer. A lifting shaft is connected to the annealing barrel through a fixing component, used to drive the closed annealing cavity to perform lifting and rotating movements. The lifting shaft drives the annealing barrel to perform lifting and rotating movements, significantly improving the heating uniformity of the wafer during high-temperature annealing. The dynamic adjustment function can alleviate thermal stress caused by differences in the thermal expansion coefficients of materials during heating and cooling, preventing wafer warping or cracking.

Description

Technical Field

[0001] This utility model relates to the field of semiconductor manufacturing equipment technology, specifically to a silicon carbide substrate wafer annealing fixture. Background Technology

[0002] Silicon carbide wafer annealing fixtures are core equipment used in semiconductor manufacturing for high-temperature heat treatment of silicon carbide materials. They are mainly used for activation annealing after ion implantation, ohmic contact formation, and material stress release.

[0003] Existing annealing fixtures are mostly fixed tray structures, which have obvious defects. Fixed structures cannot avoid the inherent non-uniformity of the temperature field inside the furnace, resulting in uneven heating of wafers at different locations or even in different batches, causing device parameter dispersion and reduced yield. Small differences in the coefficients of thermal expansion between the fixture and the wafer can trigger huge thermal stress during rapid thermal cycling, which may lead to wafer warping or cracking. At high temperatures, impurities in the graphite fixture may contaminate the wafer, and elements on the wafer surface are easily volatilized, affecting electrical performance.

[0004] Therefore, there is an urgent need for a new type of annealing fixture that can significantly improve temperature uniformity, reduce thermal stress, and suppress contamination. Utility Model Content

[0005] The purpose of this invention is to overcome the problems in the prior art and provide a silicon carbide substrate wafer annealing fixture. By dynamically adjusting the position of the fixture, uniform heating of the wafer can be achieved, and a closed structure can be used to reduce pollution and volatilization.

[0006] This invention provides a silicon carbide substrate wafer annealing fixture, including an annealing barrel, a lifting shaft, and a fixing component. The annealing barrel has an internal groove for supporting the wafer, and at least two annealing barrels can interlock with each other via protrusions on their sidewalls to form a closed annealing chamber. The lifting shaft is connected to the annealing barrel through the fixing component and is used to drive the closed annealing chamber to perform lifting and rotating movements.

[0007] Preferably, the depth of the groove is 2mm-7mm, preferably 5mm, to effectively constrain the wafer and avoid warping caused by differences in thermal expansion coefficients.

[0008] Preferably, the annealing barrel, lifting shaft, and fixing components are all made of high-purity isostatic graphite to ensure structural stability, chemical inertness, and high purity at high temperatures, and to reduce metal impurity contamination.

[0009] Preferably, the width of the groove can accommodate two wafers. By placing the activated surfaces of the two wafers together, surface volatilization during the high-temperature processing can be effectively suppressed.

[0010] Compared with the prior art, the beneficial effects of this utility model are: The lifting and rotating motion of the annealing barrel driven by the lifting shaft significantly improves the heating uniformity of the wafer during high-temperature annealing. This structure effectively overcomes the differences in heat treatment between different parts of the wafer caused by uneven temperature field distribution in traditional fixed fixtures, greatly improving the consistency of device parameters across the entire wafer and batches, thereby increasing product yield. At the same time, the dynamic adjustment function can alleviate thermal stress caused by differences in the thermal expansion coefficients of materials during heating and cooling, preventing wafer warping or cracking. The fixture uses high-purity graphite material and features a closed design, effectively suppressing impurity contamination and element volatilization on the wafer surface under high-temperature conditions, ensuring the stability of the electrical performance of silicon carbide wafers. The overall structure is simple and reliable, and the operation is flexible, making it suitable for large-scale semiconductor manufacturing applications with significant production practicality and economy. Attached Figure Description

[0011] Figure 1 This is a schematic diagram of the overall structure of this utility model.

[0012] Figure 2 This is a schematic diagram of the internal structure of the annealing barrel of this utility model.

[0013] Figure 3 This is a schematic diagram of the lifting shaft and structure of this utility model.

[0014] Figure 4 This is a schematic diagram of the fastener structure of this utility model.

[0015] Explanation of reference numerals in the attached drawings: 1. Annealing barrel; 11. Groove; 12. Protrusion; 13. Butt groove; 14. Threaded hole; 2. Lifting shaft; 3. Fixing component; 4. Connecting hole. Detailed Implementation

[0016] The following is in conjunction with the appendix Figures 1-4 To make the objectives, technical solutions, and advantages of the embodiments of this utility model clearer, the technical solutions of the embodiments of this utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this utility model. Based on the described embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this utility model. Unless otherwise defined, the technical or scientific terms used herein should have the ordinary meaning understood by those skilled in the art to which this utility model pertains.

[0017] The terms "first," "second," and similar words used in this utility model patent application specification and claims do not indicate any order, quantity, or importance, but are merely used to distinguish different components. Terms such as "comprising" or "including" mean that the element or object preceding the word encompasses the elements or objects listed after the word and their equivalents, without excluding other elements or objects. Terms such as "inner," "outer," "upper," "lower," "far," "near," "front," and "rear" are only used to indicate relative positional relationships. When the absolute position of the described object changes, the relative positional relationship may also change accordingly. The drawings in this utility model are not strictly drawn to scale; the specific dimensions and quantity of each structure can be determined according to actual needs. The drawings described in this utility model are only structural schematic diagrams.

[0018] This invention provides a silicon carbide substrate wafer annealing fixture, such as... Figures 1-4 As shown, the assembly includes an annealing barrel 1, which is formed by two symmetrically arranged annealing half-barrels joined together. The side walls of the pair of annealing half-barrels are respectively provided with mutually cooperating protrusions 12 and docking grooves 13 for positioning and fitting, so that the pair of annealing half-barrels together form a closed annealing cavity, which is provided with a groove 11 for supporting silicon carbide wafers; a lifting shaft 2, which is set above the annealing barrel 1; and a fixing member 3, which is used to connect the annealing barrel 1 and the lifting shaft 2. The lifting shaft 2 is configured to drive the annealing barrel 1 to perform lifting and rotating movements.

[0019] In this embodiment, the lifting shaft 2 drives the annealing barrel 1 to move up, down, and rotate, which significantly improves the heating uniformity of the wafer during the high-temperature annealing process. This structure effectively overcomes the differences in heat treatment of different parts of the wafer caused by the uneven temperature field distribution in the furnace in traditional fixed fixtures, greatly improving the consistency of device parameters between the whole wafer and batches, thereby improving product yield. At the same time, the dynamic adjustment function can alleviate the thermal stress caused by the difference in the thermal expansion coefficient of materials during the heating and cooling process, avoiding wafer warping or cracking. The fixture uses high-purity graphite material and is designed with a closed structure, which effectively suppresses impurity contamination and element volatilization on the wafer surface under high temperature environment, ensuring the stability of the electrical performance of silicon carbide wafers. The overall structure is simple and reliable, flexible in operation, and suitable for large-scale semiconductor manufacturing applications, with significant production practicality and economy.

[0020] Preferred, such as Figures 1-2 As shown, there are at least two annealing barrels 1. The at least two annealing barrels 1 can be connected to each other and positioned and fitted by the mutually cooperating protrusions 12 and the docking grooves 13 on their side walls to form a closed annealing cavity.

[0021] In this embodiment, at least two annealing barrels 1 are interlocked to form a closed annealing chamber, further improving the sealing performance and thermal uniformity of the tooling. This structure effectively isolates external thermal disturbances and contamination, avoids the impact of atmospheric fluctuations at high temperatures on the wafer surface quality, and ensures that multiple wafers are processed in a consistent environment, significantly improving process repeatability and batch-to-batch uniformity.

[0022] Preferred, such as Figure 1 As shown, the depth of groove 11 is 2mm-7mm.

[0023] In this embodiment, the depth of the groove 11 is limited to the range of 2mm–7mm, preferably 5mm. This can fix the wafer while avoiding mechanical compression or stress concentration caused by the difference in thermal expansion coefficients, preventing the wafer from warping or breaking during the high-temperature process, and improving the stability and yield of the annealing process.

[0024] Preferred, such as Figures 1-3 As shown, the top of the annealing barrel 1 is provided with a threaded hole 14, and the bottom of the lifting shaft 2 is fixedly connected to a connecting plate. The connecting plate is provided with a connecting hole corresponding to the threaded hole 14. The fastener 3 is a bolt that cooperates with the threaded hole 14 and the connecting hole 4, which is used to realize the detachable connection between the annealing barrel 1 and the lifting shaft 2.

[0025] In this embodiment, bolts are used to achieve a detachable connection between the annealing barrel 1 and the lifting shaft 2. This not only makes assembly flexible and maintenance convenient, but also ensures the mechanical stability and reliability of the connection structure under high temperature conditions, avoids connection failure caused by thermal deformation, and extends the service life of the tooling.

[0026] Preferred, such as Figures 1-3 As shown, there are four threaded holes 14 and four connecting holes, which are symmetrically distributed.

[0027] In this embodiment, the design of four symmetrically distributed threaded holes 14 and connecting holes ensures uniform force distribution, enhances the stability and balance of the overall structure, reduces vibration and displacement during high-speed rotation or lifting, ensures precise wafer positioning, and further improves the consistency of heat treatment.

[0028] Preferred, such as Figures 1-4 As shown, the annealing barrel 1, the lifting shaft 2, and the fixing part 3 are all made of high-purity isostatic graphite material.

[0029] In this embodiment, all components are made of high-purity isostatic graphite material, which has excellent high-temperature stability, chemical inertness and low pollution characteristics, effectively preventing metal impurities from diffusing to the wafer, ensuring the electrical performance of the device, and extending the service life of the tooling in extreme temperature environments.

[0030] Preferred, such as Figures 1-3As shown, the width of the groove 11 is configured to accommodate two silicon carbide wafers, and the active surfaces of the two wafers can be placed in relative contact. The lifting shaft 2 is driven by an external drive mechanism to perform programmed or manual lifting and rotation actions.

[0031] In this embodiment, by placing the two wafer activation surfaces together in the same groove 11, a self-shielding effect is formed, which significantly suppresses the volatilization of elements such as silicon and carbon at high temperatures, reduces surface defects, and improves the consistency of ohmic contact quality and device performance. The lifting and rotation control can be achieved by external driver through programmed or manual control, and the motion parameters can be flexibly adjusted according to actual process requirements to adapt to different furnace types and temperature profiles, thereby enhancing process controllability and applicability, and improving production efficiency and automation level.

[0032] Although embodiments of the present invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the present invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A silicon carbide substrate wafer annealing fixture, characterized in that, include: The annealing barrel (1) is formed by connecting two symmetrically arranged annealing half barrels. The side walls of the pair of annealing half barrels are respectively provided with mutually cooperating protrusions (12) and docking grooves (13) for positioning and fitting, so that the pair of annealing half barrels together form a closed annealing cavity, and a groove (11) for supporting silicon carbide wafers is provided inside. The lifting shaft (2) is positioned above the annealing barrel (1); A fastener (3) is used to connect the annealing barrel (1) and the lifting shaft (2), the lifting shaft (2) being configured to drive the annealing barrel (1) to perform lifting and rotating movements.

2. The silicon carbide substrate wafer annealing fixture as described in claim 1, characterized in that, The depth of the groove (11) is 2mm-7mm.

3. The silicon carbide substrate wafer annealing fixture as described in claim 1, characterized in that, The annealing barrel (1) has a threaded hole (14) at the top, and a connecting plate is fixedly connected to the bottom of the lifting shaft (2). The connecting plate has a connecting hole corresponding to the threaded hole (14). The fixing member (3) is a bolt that cooperates with the threaded hole (14) and the connecting hole (4) to realize the detachable connection between the annealing barrel (1) and the lifting shaft (2).

4. The silicon carbide substrate wafer annealing fixture as described in claim 3, characterized in that, The number of threaded holes (14) and connecting holes are both four, and they are symmetrically distributed.

5. The silicon carbide substrate wafer annealing fixture as described in claim 1, characterized in that, The annealing barrel (1), lifting shaft (2) and fixing component (3) are all made of high-purity isostatic graphite material.

6. The silicon carbide substrate wafer annealing fixture as described in claim 1, characterized in that, The width of the groove (11) is configured to accommodate two silicon carbide wafers, and the active surfaces of the two wafers can be placed in relative contact.

7. The silicon carbide substrate wafer annealing fixture as described in any one of claims 1-6, characterized in that, The lifting shaft (2) is driven by an external drive mechanism to perform programmed or manual lifting and rotation actions.

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