A quartz tube vacuum inert gas drier for synthesizing semiconductor crystals

Abstract

The application discloses a quartz tube vacuum inert gas drying mechanism for semiconductor crystal synthesis, and belongs to the technical field of polycrystalline indium phosphide production equipment. The drying mechanism comprises a quartz tube fixing support, a limiting fixing plate, an electric resistance heater, a vacuum pump mechanism, an inert gas filling mechanism, a sealing joint and a bellows. The limiting fixing plate is provided with a semicircular hole for clamping the end of the quartz tube, and the bellows is connected with the quartz tube, the vacuum pump mechanism and the inert gas filling mechanism through the sealing joint. The vaporized water vapor in the tube is synchronously extracted during the whole drying and heating process, high-purity inert gas is introduced when the pressure in the tube is reduced to below 100 Pa, and the bellows simultaneously realizes pipeline sealing, deformation compensation and gas conveying. The matched drying process can synchronously process multiple tubes, relies on negative pressure to accelerate water vapor evaporation, and uses inert gas to isolate external water vapor, thereby solving the problems of incomplete traditional drying and water removal and easy moisture return of the quartz tube, the dried quartz tube can be directly used for polycrystalline indium phosphide synthesis, and the drying efficiency and cleanliness meet the high-purity semiconductor production requirements.

Description

Technical Field

[0001] This invention relates to the technical field of polycrystalline indium phosphide production equipment, specifically to a quartz tube vacuum inert gas drying mechanism. Background Technology

[0002] Indium phosphide (IPS) is a strategically important semiconductor material with significant applications in optical communication, millimeter-wave high-frequency, low-noise, and broadband microelectronics integration. IPS is also a preferred material in the terahertz field. High-frequency, low-noise devices made with semi-insulating IPS are key components for next-generation radar and satellite communications. Before preparing IPS single crystals, In and P meeting certain purity requirements must first be synthesized into polycrystalline IPS compounds. Only on this basis can IPS single crystals be further prepared. The production process of polycrystalline IPS requires drying the quartz tube, but existing drying systems cannot effectively dry the inside of the quartz tube.

[0003] Existing drying equipment has two types of defects: CN212842536U discloses a quartz tube hot air drying box that relies solely on external hot air to heat the outer wall of the quartz tube, without an internal vacuum dehumidification pipeline, and therefore cannot quickly remove deep moisture from the inner wall of the quartz tube. CN106319630A discloses a vacuum gas filling process for gallium arsenide single crystal growth. Although a vacuum pump and inert gas pipeline are set up, they are only used for deoxygenation before high-temperature synthesis and are not synchronized with the heating and drying process. There is no process of continuously removing vaporized water vapor during the heating process and filling with protective gas at a low pressure threshold of 100Pa. After drying, the quartz tube is prone to reabsorbing water vapor.

[0004] Traditional drying equipment lacks an integrated sealed corrugated pipe system, making it impossible to simultaneously achieve heating, negative pressure extraction of water vapor, and inert gas isolation of water vapor. As a result, the drying efficiency is low and the cleanliness cannot meet the production requirements of high-purity indium phosphide. Summary of the Invention

[0005] The purpose of this invention is to address the shortcomings of existing technologies by proposing a quartz tube drying system for polycrystalline indium phosphide production.

[0006] To achieve the above objectives, the present invention adopts the following technical solution: A quartz tube drying system for polycrystalline indium phosphide production includes a fixed base plate and a movable base plate installed at both ends, with casters at the bottom of both the fixed and movable base plates; a resistance heater for drying the quartz tube body; a quartz tube fixing bracket on the top of the fixed base plate for fixing the quartz tube body; a movable cover for covering the quartz tube body during the drying process; side panels for shielding the heat inside the cover during the drying process; a vacuum pump mechanism for removing water vapor from the quartz tube body during the drying process; and an inert gas filling mechanism for filling the quartz tube body with inert gas after evacuating the quartz tube body.

[0007] Preferably, the side of the quartz tube fixing bracket is provided with a groove for placing the quartz tube body.

[0008] Preferably, the side panel of the box includes vertically spliced ​​limiting and fixing plates, and semi-circular holes are opened on the sides of two adjacent limiting and fixing plates for supporting and limiting the end of the quartz tube body; it also includes a support plate for limiting the movement of the box cover.

[0009] Preferably, the quartz tube body extends to the side of the limiting and fixing plate away from the box cover and is connected to a corrugated pipe through a sealing joint. The end of the corrugated pipe away from the quartz tube body is connected to an inert gas inflation mechanism.

[0010] Preferably, the guide rail mechanism includes a first slide rail disposed on a fixed base plate and a second slide rail disposed on a movable base plate; the cover is provided with pulleys adapted to the first and second slide rails.

[0011] Preferably, both the fixed base plate and the movable base plate are provided with limit buckles; the side of the box cover is provided with a limit component, which is used to engage with the limit buckles and limit the box cover.

[0012] Preferably, it also includes a support frame for supporting the inert gas filling mechanism.

[0013] Preferably, the resistance heaters are distributed on the top of the fixed base plate and on the inner wall of the box cover.

[0014] The beneficial effects of this invention are as follows: The quartz tube body is fixed to the base plate using a quartz tube fixing bracket. The lid is slid to cover the quartz tube body. A resistance heater is used to heat and dry the quartz tube body. During the drying process, a vacuum pump mechanism evacuates the inside of the quartz tube body to remove water vapor and other impurities in a timely manner. When the pressure inside the quartz tube body is reduced to below 100Pa, an inert gas filling mechanism is used to fill the quartz tube body with inert gas to keep the inside of the quartz tube body dry and clean. Multiple quartz tube bodies can be dried simultaneously, resulting in high drying efficiency and greater energy saving. Attached Figure Description

[0015] Figure 1 This is a side view of a quartz tube drying system for polycrystalline indium phosphide production, as proposed in an embodiment of the present invention. Figure 2 This is a schematic diagram of the overall structure of a quartz tube drying system for polycrystalline indium phosphide production, as proposed in an embodiment of the present invention.

[0016] In the diagram: 1-Fixed base plate, 2-Movable wheels, 3-Support frame, 4-Vacuum pump mechanism, 5-Inert gas filling mechanism, 6-Bellwall, 7-Sealing joint, 8-Box side plate, 81-Support plate, 82-Limit fixing plate, 9-Quartz tube fixing bracket, 10-Quartz tube body, 11-Box cover, 12-Guide rail mechanism, 121-First slide rail, 122-Second slide rail, 13-Movable base plate, 14-Limiting component, 15-Limiting buckle. Detailed Implementation

[0017] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments.

[0018] Reference Figures 1 to 2 A quartz tube drying system for polycrystalline indium phosphide production includes a fixed base plate 1 and a movable base plate 13 installed at both ends, with casters 2 at the bottom of both the fixed base plate 1 and the movable base plate 13; a resistance heater for drying the quartz tube body 10; a quartz tube fixing bracket 9 on the top of the fixed base plate 1 for fixing the quartz tube body 10; a movable cover 11 for covering the quartz tube body 10 during the drying process; side panels 8 for shielding the heat inside the cover 11 during the drying process; a vacuum pump mechanism 4 for removing water vapor from the quartz tube body 10 during the drying process; and an inert gas filling mechanism 5 for filling the quartz tube body 10 with inert gas after evacuation.

[0019] The quartz tube body 10 is fixed to the base plate 1 by the quartz tube fixing bracket 9. The cover 11 is slid to cover the quartz tube body 10. The quartz tube body 10 is heated and dried by the resistance heater. During the drying process, the vacuum pump mechanism 4 evacuates the inside of the quartz tube body 10 to remove water vapor and other impurities in time. When the pressure inside the quartz tube body 10 is evacuated to below 100Pa, the inert gas filling mechanism 5 fills the inside of the quartz tube body 10 with inert gas to keep the inside of the quartz tube body 10 dry and clean.

[0020] In a preferred embodiment of the present invention, the resistance heater is a coil-type resistance heater.

[0021] In a preferred embodiment of the present invention, the side of the quartz tube fixing bracket 9 is provided with a groove for placing the quartz tube body 10.

[0022] As a preferred embodiment of the present invention, the side panel 8 of the box includes vertically spliced ​​limiting and fixing plates 82, and semi-circular holes are opened on the sides of two adjacent limiting and fixing plates 82 for supporting and limiting the end of the quartz tube body 10; it also includes a support plate 81 for limiting the movement of the box cover 11.

[0023] In a preferred embodiment of the present invention, the quartz tube body 10 extends to the side of the limiting and fixing plate 82 away from the box cover 11 and is connected to a bellows 6 through a sealing joint 7. The end of the bellows 6 away from the quartz tube body 10 is connected to the inert gas inflation mechanism 5.

[0024] In a preferred embodiment of the present invention, the corrugated pipe 6 is made of materials such as plastic or metal. In this embodiment, the corrugated pipe 6 is preferably made of metal.

[0025] In a preferred embodiment of the present invention, the guide rail mechanism 12 includes a first slide rail 121 disposed on a fixed base plate 1 and a second slide rail 122 disposed on a movable base plate 13. The cover 11 is provided with pulleys adapted to the first slide rail 121 and the second slide rail 122. After the quartz tube body 10 is fixed, the cover 11 is pushed to slide on the second slide rail 122 and the first slide rail 121, so that the cover 11 slides onto the fixed base plate 1 and covers the quartz tube body 10 for drying. After drying, the cover 11 is pushed to slide onto the movable base plate 13, which facilitates the loading and unloading of the quartz tube body 10.

[0026] In a preferred embodiment of the present invention, both the fixed base plate 1 and the movable base plate 13 are provided with limiting buckles 15; the side of the box cover 11 is provided with a limiting member 14, which is used to engage with the limiting buckle 15 and limit the box cover 11. After the box cover 11 has moved, the limiting buckle 15 engages with the limiting member 14, thereby limiting the box cover 11 and preventing the box cover 11 from sliding and affecting its use.

[0027] In a preferred embodiment of the present invention, a support frame 3 is also included for supporting the inert gas filling mechanism 5.

[0028] In a preferred embodiment of the present invention, resistance heaters are distributed on the top of the fixed base plate 1 and on the inner wall of the box cover 11.

[0029] The quartz tube body 10 is fixed to the base plate 1 by the quartz tube fixing bracket 9. The cover 11 is slid to cover the quartz tube body 10. The quartz tube body 10 is heated and dried using a resistance heater. During the drying process, the vacuum pump mechanism 4 evacuates the inside of the quartz tube body 10 to remove water vapor and other impurities. When the pressure inside the quartz tube body 10 is reduced to below 100 Pa, inert gas is introduced into the quartz tube body 10 through the inert gas filling mechanism 5 to maintain the quartz tube. The body 10 is dry and clean. After the quartz tube body 10 is fixed, the cover 11 is pushed to slide on the second slide rail 122 and the first slide rail 121, so that the cover 11 slides onto the fixed base plate 1 and covers the quartz tube body 10 for drying. After drying, the cover 11 is pushed to slide onto the movable base plate 13, which facilitates the loading and unloading of the quartz tube body 10. After the cover 11 is moved, the limiting buckle 15 is engaged with the limiting member 14, thereby limiting the cover 11 and preventing the cover 11 from sliding and affecting its use.

[0030] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and inventive concept of the present invention, should be covered within the scope of protection of the present invention.

[0031] This application is a divisional application of the invention patent application No. 202210353014.6, filed on April 1, 2022, entitled "A Quartz Tube Drying System for Polycrystalline Indium Phosphide Production". The original parent application describes two independent technical solutions: one is a movable drying machine frame with a split base plate, slide rail, and sliding box cover; the other is a vacuum heating and sealed gas path drying mechanism for quartz tubes adapted for polycrystalline indium phosphide production. The two solutions do not belong to the same general inventive concept and do not meet the unity of invention requirement, therefore this divisional application is split.

[0032] This divisional application completely eliminates the fixed base plate, movable base plate, guide rails, casters, limit buckles, and other frame movement structures, protecting only the drying mechanism and its supporting drying process, which includes quartz tube clamping and positioning, resistance heating, simultaneous heating and vacuum steam extraction, bellows-sealed gas path, and 100Pa threshold inert gas replacement. All structural, process parameters, and component features of this divisional application are fully described in the original text of the original application, and there is no new technical content exceeding the scope of the original application.

Claims

1. A quartz tube vacuum inert gas drying mechanism for semiconductor crystal synthesis, characterized in that, include: Quartz tube fixing bracket, limiting fixing plate, resistance heater, vacuum pump mechanism, inert gas charging mechanism, sealing joint, bellows; The limiting and fixing plate has a semi-circular clamping hole for inserting and limiting the end of the quartz tube; The resistance heaters are distributed around the outer wall of the quartz tube to heat the entire quartz tube. One end of the bellows is sealed and connected to the end of the quartz tube that passes through the limiting and fixing plate through a sealing joint, and the other end of the bellows is divided into two paths that are respectively connected to the vacuum pump mechanism and the inert gas filling mechanism. The vacuum pump mechanism is configured such that: throughout the entire process of heating and drying the quartz tube, a negative pressure is continuously drawn inside the quartz tube to exhaust the heated and vaporized water vapor inside the tube to the outside. The inert gas filling mechanism is set with a pressure linkage threshold: when the vacuum pump draws the internal pressure of the quartz tube to 100Pa or below, inert gas is filled into the quartz tube to isolate air and moisture and maintain the tube's cleanliness and dryness. The corrugated pipe simultaneously achieves three functions: pipeline deformation compensation, vacuum sealing, and inert gas transportation.

2. The quartz tube vacuum inert gas drying mechanism for semiconductor crystal synthesis according to claim 1, characterized in that, The limiting and fixing plate is a structure of multiple vertically spliced ​​pieces. Adjacent limiting and fixing plates are aligned to form a pair of semi-circular holes to clamp the quartz tube. A support plate is also provided to limit the sliding stroke of the external drying oven lid.

3. The quartz tube vacuum inert gas drying mechanism for semiconductor crystal synthesis according to claim 1, characterized in that, The resistance heater is a coil-type resistance heater, which is installed in two places: one is attached to the top surface of the quartz tube fixing bracket, and the other is arranged on both sides of the inner wall of the box covering the quartz tube, so as to realize synchronous and uniform heating inside and outside the quartz tube.

4. The quartz tube vacuum inert gas drying mechanism for semiconductor crystal synthesis according to claim 1, characterized in that, A vertical support frame is also provided, and the inert gas inflation mechanism is fixedly installed on the support frame. The bottom of the support frame is equipped with casters, which can move synchronously with the quartz tube fixing bracket.

5. The quartz tube vacuum inert gas drying mechanism for semiconductor crystal synthesis according to claim 1, characterized in that, The side of the quartz tube fixing bracket has multiple grooves, and each groove independently holds a quartz tube, so as to realize the simultaneous vacuum drying and simultaneous inert gas replacement of multiple quartz tubes.

6. A method for clean drying of quartz tubes produced by polycrystalline indium phosphide production, characterized in that, The drying process, performed using the drying mechanism described in any one of claims 1-5, includes the following steps: S1. Insert multiple quartz tubes to be dried into the groove of the quartz tube fixing bracket, and pass the end of the quartz tube through the semi-circular hole of the limiting fixing plate and connect it to the corrugated pipe through the sealing joint. S2. Close the outer cover and start the resistance heater to heat the quartz tube as a whole. S3. Simultaneously with heating, the vacuum pump mechanism is activated to continuously remove vaporized water vapor from the quartz tube and monitor the vacuum level inside the tube in real time. S4. When the pressure inside the tube drops below the threshold of 100Pa, the inert gas filling mechanism is automatically activated to fill the quartz tube with high-purity inert gas to replace the residual water vapor and air inside the tube. S5. After drying, maintain positive pressure of inert gas inside the tube, open the box cover and take out the quartz tube directly for the polycrystalline indium phosphide synthesis process.

7. The method for clean drying of quartz tubes used in the production of polycrystalline indium phosphide according to claim 6, characterized in that, The inert gas used is high-purity argon. After filling the tube, it is kept under pressure for 3-8 minutes to fully isolate oxygen and water vapor.

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