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JP-7855689-B2 - Liquid filter device equipped with a heat shield

JP7855689B2JP 7855689 B2JP7855689 B2JP 7855689B2JP-7855689-B2

Inventors

  • マハウィリ イマド

Assignees

  • エドワーズ バキューム リミテッド ライアビリティ カンパニー

Dates

Publication Date
20260508
Application Date
20221108
Priority Date
20211116

Claims (15)

  1. A liquid filter device for semiconductor process waste, A housing having a filter chamber, a process waste inlet, a process waste outlet, and a supply pipe communicating with the process waste inlet and the filter chamber, wherein the supply pipe has a supply pipe outlet, the filter chamber forms a liquid tank for holding filter liquid, and the process waste outlet communicates with the filter chamber, A deflection surface disposed between the filter liquid and the outlet of the supply pipe, wherein the deflection surface deflects the process waste flowing from the supply pipe so as to prevent the process waste from directly colliding with the filter liquid, and further absorbs heat from the process waste, A first cup-shaped body that forms the deflection surface and forms a first volume into which the process waste flows in from the supply pipe, Equipped with , A liquid filter device in which the deflection surface is formed by a stainless steel plate of the first cup-shaped body that absorbs heat from the process waste .
  2. The liquid filter device according to claim 1 , wherein the stainless steel plate is non-porous.
  3. The liquid filter apparatus according to claim 1, wherein the supply pipe includes an open distal end, and the open distal end forms the outlet of the supply pipe.
  4. The liquid filter apparatus according to claim 1, wherein the supply pipe outlet has a predetermined diameter, the deflection surface has an outer circumference, and the outer circumference of the deflection surface is larger than the diameter of the supply pipe outlet.
  5. The liquid filter apparatus according to claim 1, wherein the housing includes a discharge chamber between the liquid tank and the process waste outlet for guiding the flow of filtered process waste from the liquid tank to the process waste outlet.
  6. The liquid filter apparatus according to claim 5 , wherein the housing includes an internal conduit that is in fluid communication with the liquid tank and the discharge chamber, and guides the flow of the filtered process waste from the liquid tank to the discharge chamber.
  7. The liquid filter apparatus according to claim 1, further comprising a filter liquid control system for controlling the inflow and outflow of the filter liquid into the liquid tank.
  8. The liquid filter apparatus according to claim 7 , wherein the filter liquid control system comprises a control device and a fluid circuit, and the control device controls the fluid circuit to adjust the flow of filter liquid into and out of the liquid tank.
  9. The liquid filter device according to claim 7 , further comprising at least one support that supports the deflection surface above the filter liquid in the liquid tank.
  10. The liquid filter device according to claim 1 , wherein the first cup-shaped body has a cylindrical wall positioned at a distance from the supply pipe.
  11. The liquid filter apparatus according to claim 1, further comprising a second cup-shaped body, wherein the first cup-shaped body is positioned within the second cup-shaped body, and the second cup-shaped body forms a second volume through which the process waste flows from the first cup-shaped body and to the process waste outlet.
  12. The liquid filter device according to claim 11 , wherein at least one of the first cup-shaped body and the second cup-shaped body is made of stainless steel.
  13. A method for separating solid materials from process waste in a semiconductor processing system using a liquid filter, A step of providing a liquid filter comprising a supply pipe, a filter chamber , an outlet , and a cup-shaped body , wherein the supply pipe has a supply pipe outlet , the cup-shaped body forms a deflection surface and a volume into which the process waste flows from the supply pipe, and the deflection surface is formed of a stainless steel plate , The steps include forming a liquid tank in the filter chamber, The steps include: holding the filter liquid in the liquid tank below the deflection surface ; The steps include providing a secondary pre-filter fluid path from the supply pipe outlet to the liquid tank using the cup-shaped body , A step of introducing the process waste from the supply pipe into the secondary pre-filter fluid path of the filter chamber, wherein the deflecting surface deflects the process waste so as to prevent the process waste flowing in from the supply pipe from directly colliding with the filter fluid, and absorbs heat from the process waste. The steps include: guiding the process waste to the secondary pre-filter fluid path , and then guiding the process waste to the liquid tank of the filter chamber; A method that includes this.
  14. The method according to claim 13 , further comprising the step of making the deflection surface larger than the diameter of the supply pipe outlet.
  15. The method according to claim 13 , further comprising the step of supporting the deflection surface above the filter liquid in the liquid tank.

Description

(Related applications) The present invention relates to U.S. Patent Application No. 16/893,504, filed on June 5, 2020, the entire disclosure of which is incorporated herein by reference. Typically, semiconductor device manufacturing utilizes the conversion of specific chemicals through oxidation at moderate to high silicon wafer temperatures to form the desired thin films that constitute the circuit layers of the semiconductor device. For example, in the chemical vapor deposition (CVD) process, silicon dioxide films deposited on a silicon wafer are formed by the oxidation of silane with oxygen at a wafer temperature of approximately 400°C and a processing chamber pressure of approximately 300 mTorr. Silicon dioxide films can also be formed by oxidizing vaporized tetraethylsiloxane (TOES) with oxygen and ozone under nearly identical processing conditions. Furthermore, silicon dioxide films can be formed at lower temperatures using low-pressure vapor-phase plasma enhancement (PECVD). Another process involves reacting silane with ammonia to form silicon nitride at low pressure and moderate wafer temperatures. In almost all other CVD reactions, such as the formation of tungsten and tungsten silicide thin films, approximately 75% of the gas-supplied reactants supplied to the processing chamber pass through the chamber unconverted. The typical semiconductor processing chamber discharge is a gaseous stream, which is low-pressure and consists of unconverted feed reactants, reaction byproducts, diluent nitrogen carrier gas, and particles. These particles are byproducts of gas-phase reactants of the reactants heated in the gas phase, and continue to form and increase in volume along a foreline extending over the distance between the processing chamber and the vacuum pump. Figure 1 is a schematic diagram of a typical CVD or PECVD system comprising a processing chamber connected to a vacuum pump via a foreline. The vacuum pump is connected via a discharge line to a typical gas discharge abatement system, which uses a natural gas flame to break down unreacted process gases and then removes acidic gaseous byproducts in a gas/water absorption column. The products of such abatement systems typically consist of an acidic wastewater stream, which is usually neutralized and discharged, and a gaseous stream containing particulate matter, which is released into the atmosphere after passing through a large-surface-area mechanical particle filter. Particles cover all connection lines between the processing chamber, vacuum pump, and abatement system, frequently clogging and blocking these lines, resulting in significant maintenance downtime and substantial additional operating costs. Often, vacuum pumps become inoperable due to high levels of particle buildup, forcing shutdown. Vacuum pumps are periodically removed and replaced from such lines at very high material and labor costs. In some processes, mechanical filters are placed in the vacuum foreline to capture these particles and extend the life of the vacuum pump. Often, both the foreline and pump discharge lines are heated to prevent condensation of unconverted condensable reactants, which then help absorb and agglomerate gas-containing particles, resulting in liquid/solid clumps that are extremely difficult and costly to remove. The best method for achieving particle separation from a gas-containing particle stream is to use a liquid medium. For example, particles can be separated from a large gas flow by passing the gas-containing particle stream through a high-flow water shower. High-level particle separation into a water stream can be achieved by appropriately sizing the tank volume and water discharge rate. While such a separation process is effective and economical when using water, it cannot be used in semiconductor processes due to the possibility of harmful chemical reactions between reactants in the gas stream and water, and the extremely high water vapor pressure in low-pressure forelines. In vacuum CVD and PECVD semiconductor processes, molecular water present in the foreline diffuses backward into the processing chamber itself, degrading the chemical composition of the semiconductor thin film being processed. This is a schematic diagram of a prior art CVD or PECVD system, which consists of a processing chamber connected to a vacuum pump via a foreline.This is a schematic diagram of a liquid filter device for separating solids from semiconductor process gases.This is a schematic diagram of a liquid filter device with a modified gas flow path.This is a schematic diagram of a liquid filter device equipped with a venturi.This is a schematic diagram of a liquid filter device equipped with a heat shield.This is a schematic diagram of a liquid filter apparatus that agitates the filter liquid.This diagram is similar to Figure 6, which shows the sequence of valve openings.This diagram is similar to Figure 6, which shows the sequence of valve openings.This diagram is simil