Clamp for liquid phase epitaxial growth process

Abstract

The utility model discloses a clamp for a liquid phase epitaxial growth process, which comprises an annular main body framework, and a fixed bracket is arranged above the annular main body framework; the fixed support is connected with the liquid phase epitaxy equipment through a connecting rod, and the clamp further comprises at least four alloy columns, a substrate supporting module, a shielding module and a stirrer module. According to the utility model, the stirrer and a clamp for mounting the substrate are combined into a whole, so that the process steps of stirring, taking out and feeding the substrate are cancelled, a large amount of time is saved, the production efficiency is improved, and the quality and effective utilization rate of crystals are greatly improved.

Description

Technical Field

[0001] The utility model relates to the field of artificial crystal growth equipment, in particular to a clamp used in a liquid phase epitaxial growth process. Background Art

[0002] Rare earth iron garnet crystal materials are generally grown by epitaxy. The actual industrial production process includes: raw material addition, furnace heating, stirring entry, stirring, stirring removal, cooling to growth temperature, substrate entry, epitaxial growth, pulling out and cooling, and wafer removal. Although the actual epitaxial growth time is generally 20-40 hours, the overall process is more than about 80 hours. One of the main reasons is that stirring, substrate entry into the furnace, and removal from the furnace take a lot of time: on the one hand, since the rod of the fixed fixture is generally made of corundum material, the stirrer must be pulled out of the furnace at a slow speed when entering the furnace; on the other hand, the substrate material is calcium magnesium zirconium doped gadolinium gallium garnet, which is very easy to crack due to excessive temperature rise during the process of entering the furnace, so the speed of entering the furnace is extremely slow. For the above reasons, a lot of time is wasted in the process of entering, pulling out, and entering the substrate. Utility Model Content

[0003] In view of the above-mentioned deficiencies in the prior art, the purpose of the utility model is to design a clamp by adding a stirrer module to the original substrate installation clamp, thereby eliminating the process steps of stirring and removing and substrate entering, saving a lot of time and improving production efficiency.

[0004] In order to achieve the above purpose, the technical solution provided by the utility model is:

[0005] A fixture for liquid phase epitaxial growth process, comprising an annular main body skeleton, on which a fixed bracket is arranged; the fixed bracket is connected to the liquid phase epitaxial equipment through a connecting rod, and the fixture also includes at least four alloy columns, a substrate support module, a shielding module and an agitator module; the alloy columns are vertically arranged below the annular main body skeleton; the substrate support module is fixedly installed on the upper part of the alloy columns to carry a wafer substrate; the shielding module is arranged between the substrate support module and the agitator module, and its area is sufficient to cover the area between the agitator module and the wafer substrate; the agitator module includes a fan blade installed on the inner side of the alloy column, and the fan blade is located below the shielding module and in contact with a liquid phase reaction medium.

[0006] Furthermore, a groove is provided on the inner side of the alloy column for accommodating and fixing the shielding module.

[0007] Furthermore, the fan blade is larger than 0.2 times the diameter of the annular main body skeleton and smaller than 0.5 times the diameter of the annular main body skeleton.

[0008] Preferably, the fan blade is a curved surface with a twisting angle of 0-10 degrees. More preferably, the bending and twisting direction is consistent with the rotation direction of the clamp.

[0009] Preferably, the fan blade is a plate with a gradually decreasing width or a plate with a gradually increasing width.

[0010] Furthermore, the bottom surface of the substrate supporting module is 5 to 10 millimeters away from the top surface of the shielding module.

[0011] Furthermore, the distance between the bottom surface of the shielding module and the top of the fan blade is 0 to 5 mm.

[0012] Furthermore, the shielding module is a platinum blocking sheet with a thickness less than 1 mm.

[0013] Beneficial effects of the utility model:

[0014] 1. The utility model combines the agitator module with the substrate mounting fixture, eliminating the process steps of stirring and taking out and substrate entering, saving a lot of time and improving production efficiency.

[0015] 2. Through the design of the fixture, the operation path of rare earth iron garnet single crystal growth was optimized, and the growth efficiency was improved by about 12.5%. At the same time, the speed of crystal growth was accelerated by about 8.1%. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is one of the three-dimensional structural schematic diagrams of the utility model.

[0017] Figure 2 It is another three-dimensional structural schematic diagram of the utility model, wherein the fan blade is a curved surface.

[0018] Figure 3 It is a usage state diagram of the utility model.

[0019] Figure 4 It is a top view of the utility model and a schematic diagram of two different fan blades.

[0020] Figure numerals: 1. annular main body skeleton; 2. alloy column; 3. substrate support module; 4. shielding module; 5. agitator module; 6. substrate. DETAILED DESCRIPTION

[0021] In order to better understand the technical solution of the utility model, the embodiments of the utility model are described in detail below in conjunction with specific embodiments. It should be clear that the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0022] The terms used in the embodiments of the present invention are only for the purpose of describing specific embodiments and are not intended to limit the present invention. The singular forms "a", "the" and "the" used in the embodiments of the present invention and the appended claims are also intended to include the plural forms unless the context clearly indicates other meanings. The test materials used in the present invention are all common commercial products and can be purchased on the market.

[0023] Reference Figure 1 and Figure 3 As shown, Figure 1 It is a three-dimensional structural schematic diagram of the structure of the utility model, a clamp for liquid phase epitaxial growth process, including an annular main body skeleton 1, on which a fixed bracket is arranged; the fixed bracket is connected to the liquid phase epitaxial equipment through a connecting rod, and the clamp also includes at least four alloy columns 2, a substrate support module 3, a shielding module 4 and an agitator module 5; the alloy column 2 is vertically arranged below the annular main body skeleton 1; the substrate support module 3 is fixedly installed on the upper part of the alloy column 2, carrying a substrate 6; the shielding module 4 is arranged between the substrate support module 3 and the agitator module 5, and is a platinum barrier plate with a thickness of less than 1 mm, and its area is sufficient to cover the area between the agitator module 5 and the substrate 6; the agitator module 5 includes four fan blades installed on the inner side of the alloy column 2, and the fan blades are located below the shielding module 4 and in contact with the liquid reaction medium.

[0024] Preferably, Figure 1 As shown, a groove is provided inside the alloy column 2 for accommodating and fixing the shielding module 4 .

[0025] Furthermore, the bottom end of the alloy column 2 of the fixture is compounded with a twisted and extended agitator module 5. The fan blades in the agitator module 5 are larger than 0.2 times the diameter of the annular main body frame and smaller than 0.5 times the diameter of the annular main body frame.

[0026] Preferably, Figure 2 or Figure 4 As shown in (b), the fan blade is a curved surface with a twist angle of 0-10 degrees. More preferably, the bending and twisting direction is consistent with the rotation direction of the clamp. The fan blade can also be designed as a plate with a gradually decreasing width or a plate with a gradually increasing width, such as Figure 4 (a) shown.

[0027] Furthermore, the bottom surface of the substrate supporting module 3 and the top surface of the shielding module 4 are 5 to 10 millimeters apart.

[0028] Furthermore, the distance between the bottom surface of the shielding module 4 and the top of the fan blade is 0 to 5 mm.

[0029] The process flow of liquid phase epitaxial growth of crystals before the improvement is: raw material replenishment → heating → stirring in → stirring → stirring out → cooling to growth temperature → substrate in → epitaxial growth → cooling → wafer out. The process flow of liquid phase epitaxial growth of crystals using the utility model is: raw material replenishment → heating → fixture in → stirring → cooling to growth temperature → epitaxial growth → cooling → wafer out. The use of the utility model reduces the process steps of stirring in and out, and substrate in.

[0030] The more specific process is as follows: After the raw materials are replenished and the equipment is heated up, the substrate 6 is placed on the substrate support module 3 of the fixture, and then the entire mechanism is slowly placed into the furnace. The fixture is lowered until the liquid level completely submerges the agitator module 5, but must not submerge the shielding module 4. Then the fixture of the utility model is rotated unidirectionally, and the direction of rotation is determined by the torsion direction of the bottom stirring module. The agitator module 5 is started below the liquid surface to uniformly stir the melt; ensure that the liquid flow surges upward from the center so that the melt is fully dissolved and mixed. The purpose of rotation is to fully mix the bottom melt with the upper part, so the direction of rotation needs to be determined according to the shape of the fan blades. After the set time, stop rotating and wait for the temperature to stabilize. Then, the fixture is lowered to make the wafer substrate 6 contact the liquid surface, start the normal epitaxial growth process, and complete the crystal growth. After the end, the fixture is pulled out of the liquid surface, the furnace body is cooled down, and the growing wafer is taken out to complete a growth cycle. The traditional process cycle is about 72 hours, and after improvement, the cycle using the fixture of the utility model is about 63 hours, saving 9 hours and increasing by 12.5%.

[0031] Among them, the function of the shielding module 4 is to prevent the high-temperature melt from volatilizing and splashing during the stirring process, causing irreversible damage to the substrate and reducing the yield rate of the wafer. It should be noted that by combining the agitator module 5 with the growth fixture, the agitator module 5 also stirs the melt during the crystal growth process, increasing the convection in the melt. From the mechanism of liquid phase epitaxial crystal growth, it can be seen that this effect also accelerates the rate of crystal epitaxial growth and improves efficiency. The growth time was reduced from 37h to 34h, an increase of about 8.1%.

[0032] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A fixture for liquid phase epitaxial growth process, comprising an annular main frame, on which a fixed bracket is arranged; the fixed bracket is connected to the liquid phase epitaxial device through a connecting rod, characterized in that: The fixture further comprises at least four alloy columns, a substrate support module, a shielding module and a stirrer module; the alloy columns are vertically arranged below the annular main frame; the substrate support module is fixedly installed on the upper part of the alloy columns to carry the wafer substrate; The shielding module is arranged between the substrate support module and the agitator module, and its area is sufficient to cover the area between the agitator module and the wafer substrate; the agitator module includes fan blades installed on the inner side of the alloy column, and the fan blades are located below the shielding module and in contact with the liquid reaction medium; the width of the fan blades is greater than 0.2 times the diameter of the annular main body skeleton and less than 0.5 times the diameter of the annular main body skeleton.

2. The clamp according to claim 1, characterized in that: A groove is provided inside the alloy column for accommodating and fixing the shielding module.

3. The clamp according to claim 1, characterized in that: The fan blade is a curved surface with a twisting angle of 0-10 degrees.

4. The clamp according to claim 3, characterized in that: The bending and twisting direction of the fan blade is consistent with the rotation direction of the clamp.

5. The clamp according to claim 1, characterized in that: The fan blades are plates with gradually decreasing width or plates with gradually increasing width.

6. The clamp according to claim 1, characterized in that: The bottom surface of the substrate supporting module is 5 to 10 mm away from the top surface of the shielding module.

7. The clamp according to claim 1, characterized in that: The distance between the bottom surface of the shielding module and the top of the fan blade is 0 to 5 mm.

8. The clamp according to claim 1, characterized in that: The shielding module is a platinum blocking sheet with a thickness less than 1 mm.

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