Search

CN-121977356-A - Vertical low-pressure diffusion furnace and sealing compensation method thereof

CN121977356ACN 121977356 ACN121977356 ACN 121977356ACN-121977356-A

Abstract

The invention provides a vertical low-pressure diffusion furnace and a sealing compensation method thereof, which relate to the field of semiconductor manufacturing and adopt the following scheme: the furnace door is arranged on the furnace door, the furnace door is arranged on the support in a lifting mode, a plurality of guide rods are uniformly arranged between the furnace door and the support along the circumferential direction, the guide rods penetrate through the support, springs are arranged on the guide rods, and two ends of each spring are respectively abutted to the furnace door and the support. The invention can carry out seal compensation, improves seal reliability and ensures product qualification rate.

Inventors

  • SONG DEPENG
  • LI XINZHAO

Assignees

  • 山东力冠微电子装备有限公司

Dates

Publication Date
20260505
Application Date
20260112

Claims (10)

  1. 1. The utility model provides a vertical low pressure diffusion furnace, includes furnace gate (3) and furnace body (1), be provided with sealing washer (2) on furnace gate (3), its characterized in that still includes support (4), furnace gate (3) set up on support (4), furnace gate (3) with evenly be provided with a plurality of guide bars (14) along the circumferencial direction between support (4), guide bar (14) run through support (4), be provided with spring (13) on guide bar (14), the both ends of spring (13) respectively with furnace gate (3) with support (4) butt, furnace gate (3) can be in vertical direction motion under the effect of spring (13).
  2. 2. The vertical low-pressure diffusion furnace according to claim 1, wherein a first sealing corrugated pipe (12) is arranged outside the spring (13), and the upper end and the lower end of the first sealing corrugated pipe (12) are respectively connected with the furnace door (3) and the support (4).
  3. 3. A vertical low-pressure diffusion furnace according to claim 2, characterized in that the support (4) is provided with a linear bearing (6), and the projecting end of the guide rod (14) is connected with the linear bearing (6).
  4. 4. A vertical low-pressure diffusion furnace according to claim 3, characterized in that the support (4) is arranged on a screw rod (7) in a lifting manner, the screw rod (7) is rotatably arranged on a stand column, the upper end of the screw rod (7) is connected with a lifting motor (8), and the lifting motor (8) is arranged on the stand column.
  5. 5. The vertical low-pressure diffusion furnace according to claim 4, further comprising a rotating motor (5), wherein a motor shaft (11) of the rotating motor (5) penetrates through the support (4) and the furnace door (3) upwards and then is connected with a rotating seat (18), the rotating seat (18) is located at the upper part of the furnace door (3), and a wafer boat (9) is arranged on the rotating seat (18).
  6. 6. The vertical low-pressure diffusion furnace according to claim 5, characterized in that a magnetic fluid seal (15) is arranged between the motor shaft (11) and the furnace door (3), the rotating motor (5) being arranged on the support (4) in a lifting manner.
  7. 7. The vertical low-pressure diffusion furnace according to claim 6, wherein the rotating motor (5) is arranged on the support (4) through a floating support (10), the floating support (10) comprises a cylinder body (1003), compressed gas is filled in the cylinder body (1003), a piston (1005) is arranged in the cylinder body (1003), the cylinder body (1003) is divided into a rod cavity (1002) and a rodless cavity (1004) by the piston (1005), a piston rod (1001) is arranged on the piston (1005), the piston rod (1001) is connected with a motor seat (17), the rotating motor (5) is arranged on the motor seat (17), the rodless cavity (1004) is also communicated with an overflow valve, an air inlet valve is arranged on the rodless cavity (1004), the air inlet valve is electrically connected with a controller, a spring (13) seat is arranged on the support (4), a pressure sensor I is arranged in the spring (13) seat, and the pressure sensor I is electrically connected with the controller.
  8. 8. The vertical low pressure diffusion furnace according to claim 7, wherein a second pressure sensor is arranged inside the rodless cavity (1004), and the second pressure sensor is electrically connected with the controller.
  9. 9. The vertical low-pressure diffusion furnace according to claim 8, characterized in that a second sealing bellows (16) is further provided between the rotating electric machine (5) and the magnetic fluid seal (15), and the motor shaft (11) penetrates through the second sealing bellows (16).
  10. 10. A method for compensating for the sealing of a vertical low pressure diffusion furnace according to claim 8, comprising the steps of: When a sealing gap is formed between the sealing ring (2) failure furnace body (1) and the furnace door (3), the spring (13) is gradually stretched to generate thrust to the furnace door (3), and meanwhile, the air inlet valve is opened as soon as the pressure sensor detects a signal of pressure reduction, and the floating support piece (10) drives the rotating motor (5) to ascend and generate thrust to the furnace door (3); When the pressure sensor II monitors that the pressure in the rodless cavity (1004) is continuously lower than a set threshold value, the lifting motor (8) drives the support (4) to lift, and the furnace door (3) is pushed tightly.

Description

Vertical low-pressure diffusion furnace and sealing compensation method thereof Technical Field The invention relates to the field of semiconductor manufacturing, in particular to a vertical low-pressure diffusion furnace and a sealing compensation method thereof. Background The diffusion furnace is core process equipment in the fields of microelectronics, photoelectronics and new materials, specific impurities or functional materials are uniformly doped or deposited on the surface and inside of a workpiece through a thermal diffusion principle under a high-temperature controllable atmosphere environment, the electrical and physical properties of the materials are accurately regulated and controlled, the low-pressure diffusion can improve the uniformity of air flow in a diffusion furnace tube, and the generation of turbulence is avoided, so that the diffusion uniformity is improved, the absorption efficiency of chemicals in the diffusion process is greatly improved, the consumption of the chemicals in the process can be greatly reduced, the cost is saved, and the low-pressure diffusion becomes the trend of future diffusion process development. In the prior art, the furnace door structure of the low-pressure diffusion furnace takes the negative pressure in the furnace as a core, and is designed in a rigid sealing or manual compression mode, sealing is realized mainly through the joint of the furnace door and the sealing surface of the furnace body, and the sealing effect is enhanced by matching with a sealing ring. By adopting the furnace door structure, the furnace tube temperature in the diffusion process is very high, the sealing ring is easy to melt and damage due to overhigh temperature, the service life is short, sealing failure is very easy to cause, the low-pressure environment required by decompression diffusion cannot be formed, the negative pressure condition requirement of the process cannot be met, under the action of external atmospheric pressure, gas, impurities and the like outside the reaction tube can enter the reaction tube, the preparation quality of a workpiece is seriously influenced, the product is scrapped, and meanwhile, corrosive gas in the tube can leak outside the furnace door, so that equipment metal substances outside the furnace door are corroded. Disclosure of Invention In order to solve the technical problem that the sealing performance of the low-pressure diffusion furnace in the prior art is poor, the invention provides the vertical low-pressure diffusion furnace and the sealing compensation method thereof, which can carry out sealing compensation and improve the sealing reliability. In a first aspect, the present invention provides a vertical low pressure diffusion furnace and a sealing compensation method thereof for solving the above-mentioned problems, where the vertical low pressure diffusion furnace includes a furnace door and a furnace body, the furnace door is provided with a sealing ring, and further includes a support, the furnace door is provided on the support, a plurality of guide rods are uniformly provided between the furnace door and the support along a circumferential direction, the guide rods penetrate through the support, a spring is provided on the guide rods, two ends of the spring are respectively abutted to the furnace door and the support, and the furnace door can move along a vertical direction under the action of the spring. According to the invention, the spring and the guide rod are arranged to uniformly seal and compensate after the sealing ring fails, so that a stable sealing effect is effectively maintained, the influence of the diffusion process on the product quality caused by the entry of gas outside the furnace is greatly avoided, and the environmental pollution caused by the leakage of corrosive gas in the furnace to the outside can be prevented. Further, a first sealing corrugated pipe is arranged outside the spring, and the upper end and the lower end of the first sealing corrugated pipe are respectively connected with the furnace door and the support. According to the invention, the sealing corrugated pipe I is arranged, so that the spring can be protected, and the influence of corrosion of the spring under the action of corrosive gas on the service life of the spring is avoided. Further, a linear bearing is arranged on the support, and the extending end of the guide rod is connected with the linear bearing. Further, the support is arranged on the screw in a lifting manner, the screw is arranged on the upright in a rotating manner, the upper end of the screw is connected with a lifting motor, and the lifting motor is arranged on the upright. Further, the furnace door comprises a rotating motor, a motor shaft of the rotating motor upwards penetrates through the support and the furnace door, a rotating seat is connected to the rear of the furnace door, the rotating seat is located on the upper portion of the furnace door, and a wafer boa