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CN-122028673-A - Etching machine chamber air balance characterization method, monitoring method and system

CN122028673ACN 122028673 ACN122028673 ACN 122028673ACN-122028673-A

Abstract

The invention provides an air balance characterization method, a monitoring method and a system for an etching machine chamber, which belong to the technical field of semiconductor manufacturing, wherein the air balance characterization method for the etching machine chamber comprises the steps of obtaining the exhaust pressure in the machine chamber in the etching process and obtaining the pH value of the environment in the machine chamber in the etching process; and repeating the steps for a plurality of times, and calibrating the target exhaust pressure and the target environment pH value according to the exhaust pressure, the environment pH value and the etching condition of the wafer obtained by each etching. According to the etching machine chamber air balance characterization method, the air balance of the etching machine chamber is defined through the target exhaust pressure and the target environment pH value, the air balance characterization is carried out through the number of wafer defect conditions after the etching of the machine chamber is finished, the air balance of the machine chamber can be effectively defined and characterized, and the etching process of the machine chamber is effectively monitored.

Inventors

  • LIU HAO
  • LI QI

Assignees

  • 芯恩（青岛）集成电路有限公司

Dates

Publication Date
20260512
Application Date
20241106

Claims (13)

  1. 1. The method for characterizing the air balance of the chamber of the etching machine is characterized by comprising the following steps of: Acquiring exhaust pressure in a machine cavity in the etching process, and acquiring the pH value in the machine cavity in the etching process; Acquiring the etching condition of the wafer after the etching is finished; repeating the steps for a plurality of times, and calibrating the target exhaust pressure and the target environment pH value according to the exhaust pressure, the environment pH value and the etching condition of the wafer obtained by each etching.
  2. 2. The method for characterizing air balance of a chamber of an etching machine according to claim 1, wherein the method is characterized in that the exhaust pressure in the chamber of the etching machine is obtained, and the exhaust pressure is an average value of the exhaust pressure of the chamber of the etching machine at a preset position in the etching process obtained by a plurality of times with a fixed frequency, and the environmental ph is an average value of the environmental ph in the chamber of the etching machine obtained by a plurality of times with a fixed frequency.
  3. 3. The method of claim 1, wherein calibrating the target exhaust pressure and the target environmental ph according to the exhaust pressure, the environmental ph, and the etching condition of the wafer obtained by each etching, comprises: and comparing the wafer surface image obtained after each etching with a preset standard etched wafer surface image, wherein the exhaust pressure and the environmental pH value in the etching process corresponding to the wafer surface image with the minimum difference with the standard etched wafer surface image are the target exhaust pressure and the target environmental pH value.
  4. 4. The method for monitoring the air balance of the etching machine chamber is characterized by comprising the following steps of: Acquiring exhaust pressure in a machine cavity in the etching process, and acquiring the pH value in the machine cavity in the etching process; comparing the exhaust pressure with a target exhaust pressure, and comparing the environmental pH value with a target environmental pH value; and when the difference value between the exhaust pressure and the target exhaust pressure is larger than a first preset value and the difference value between the pH value of the environment and the pH value of the target environment is smaller than a second preset value, adjusting the power of the exhaust equipment of the machine chamber.
  5. 5. The method for monitoring air balance of etching machine chamber according to claim 4, wherein the exhaust pressure in the machine chamber during etching is obtained, and the exhaust pressure is an average value of the exhaust pressure of the machine chamber at a preset position during etching obtained by using a fixed frequency for a plurality of times, and the environmental pH value is an average value of the environmental pH value in the machine chamber during etching obtained by using a fixed frequency for a plurality of times.
  6. 6. The method of claim 5, wherein comparing the exhaust pressure with a target exhaust pressure, and comparing the environmental ph with a target environmental ph further comprises: And controlling the etching machine to alarm when the difference value between the exhaust pressure and the target exhaust pressure is larger than a third preset value and/or the difference value between the pH value of the environment and the pH value of the target environment is larger than or equal to the second preset value.
  7. 7. The method of claim 6, wherein the first preset value is 0.1-0.2kpa, and/or the second preset value is 0.1-0.2, and/or the third preset value is 0.8-1.2kpa.
  8. 8. An etching machine chamber air balance monitoring system, comprising: The device comprises a base, an air pressure sensor, a liquid drop collector, a pH value tester, an exhaust device and a controller; the air pressure sensor is located on the chamber exhaust path and used for detecting exhaust pressure, the liquid drop collector is used for collecting mist liquid drops in the etching process in the chamber, the pH value tester is used for testing the pH value of the mist liquid drops to obtain environmental pH value, and the controller is used for: Acquiring exhaust pressure in a machine cavity in the etching process, and acquiring the pH value in the machine cavity in the etching process; comparing the exhaust pressure with a target exhaust pressure, and comparing the environmental pH value with a target environmental pH value; and when the difference value between the exhaust pressure and the target exhaust pressure is larger than a first preset value and the difference value between the pH value of the environment and the pH value of the target environment is smaller than a second preset value, adjusting the power of the exhaust equipment of the machine chamber.
  9. 9. The etching tool chamber air balance monitoring system of claim 8, wherein the droplet collector comprises a collection tray and a driving structure, the driving structure is configured to drive the collection tray to be in a first state or a second state, the collection tray is configured to collect mist droplets when the collection tray is in the first state, and the air pressure sensor is configured to detect the exhaust pressure, the collection tray is in the second state.
  10. 10. The etching tool chamber air balance monitoring system of claim 9, wherein, The first state is a horizontal state, the second state is a vertical state, or the first state is an extended state, and the second state is a contracted state.
  11. 11. The etching tool chamber air balance monitoring system of claim 9, wherein a hydrophobic coating is disposed within the collection tray.
  12. 12. The etching machine chamber air balance monitoring system according to claim 8, further comprising an alarm, wherein the alarm is in signal connection with the controller, and the controller is further configured to control the etching machine to alarm when a difference between the exhaust pressure and a target exhaust pressure is greater than a third preset value, and/or when a difference between the environmental ph and a target environmental ph is greater than or equal to the second preset value.
  13. 13. The etching machine chamber air balance monitoring system according to any one of claims 8 to 12, wherein the air pressure sensor is made of polyether-ether-ketone, the accuracy of the air pressure sensor is less than 0.01kpa, and the accuracy of the ph tester is 0.01.

Description

Etching machine chamber air balance characterization method, monitoring method and system Technical Field The invention belongs to the technical field of semiconductor manufacturing, and particularly relates to an etching machine chamber air balance characterization method, a monitoring method and a system. Background The wafer back process is mainly a wafer back thinning process, and after the wafer back is physically thinned, a single-chip etching machine is generally used for carrying out chemical etching thinning on the wafer back. One of the key factors affecting the etching effect of a monolithic etching tool is aerodynamics, i.e., the air balance of the tool chamber. In the etching reaction process, gas reaction products are usually generated, mist droplets are formed after the gas reaction products and solvent droplets sprayed on the surface of the wafer collide, and in order to reduce the influence of factors such as the reaction products, the volatilization of the solvent droplets and the like, an exhaust device is designed in the machine chamber. However, the excessive or insufficient exhaust rate of the exhaust device can affect the air balance of the chamber, thereby causing defects of the wafer back surface that are not in accordance with the standard to reduce the wafer yield and even discard the wafer. The existing single-chip etching machine has no effective definition on the air balance of the machine cavity, cannot characterize the air balance of the machine cavity and effectively and accurately monitor the air balance, cannot control the exhaust equipment in a system, often causes the air balance unbalance to cause the defect of an etching product, and the etching machine also has no reaction after the air balance unbalance. Disclosure of Invention The invention aims to provide an air balance characterization method, a monitoring method and a system for an etching machine chamber, the air balance characterization method, the monitoring method and the system for the etching machine chamber can effectively define the air balance of the etching chamber, effectively monitor the machine chamber to enable the etching chamber to be air balanced, and improve the etching yield of wafers. In order to achieve the purpose, the invention adopts the technical scheme that the first aspect of the invention provides an etching machine chamber air balance characterization method, which comprises the following steps: Acquiring exhaust pressure in a machine cavity in the etching process, and acquiring the pH value in the machine cavity in the etching process; Acquiring the etching condition of the wafer after the etching is finished; repeating the steps for a plurality of times, and calibrating the target exhaust pressure and the target environment pH value according to the exhaust pressure, the environment pH value and the etching condition of the wafer obtained by each etching. In an embodiment, the exhaust pressure in the chamber of the machine during the etching process is obtained, and the exhaust pressure is an average value of the exhaust pressure of the chamber of the machine at a preset position in the etching process obtained by adopting a fixed frequency for a plurality of times, and the environmental ph is an average value of the environmental ph in the chamber of the machine during the etching process obtained by adopting the fixed frequency for a plurality of times. In an embodiment, calibrating the target exhaust pressure and the target environmental ph according to the exhaust pressure, the environmental ph, and the etching condition of the wafer obtained by each etching includes: and comparing the wafer surface image obtained by each etching with a preset standard etched wafer surface image, wherein the exhaust pressure and the environmental pH value in the etching process corresponding to the wafer surface image with the minimum difference with the standard etched wafer surface image are the target exhaust pressure and the target environmental pH value. The second aspect of the invention provides a method for monitoring air balance of a chamber of an etching machine, comprising the following steps: Acquiring exhaust pressure in a machine cavity in the etching process, and acquiring the pH value in the machine cavity in the etching process; comparing the exhaust pressure with a target exhaust pressure, and comparing the environmental pH value with a target environmental pH value; and when the difference value between the exhaust pressure and the target exhaust pressure is larger than a first preset value and the difference value between the pH value of the environment and the pH value of the target environment is smaller than a second preset value, adjusting the power of the exhaust equipment of the machine chamber. In one embodiment, the exhaust pressure in the chamber of the machine during etching is obtained, and the exhaust pressure is the average value of the exhaust pressure of the ch