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CN-114496833-B - Cleaning device, cleaning system and cleaning method

CN114496833BCN 114496833 BCN114496833 BCN 114496833BCN-114496833-B

Abstract

The invention discloses a cleaning device, a cleaning system and a cleaning method, which relate to the technical field of chemical mechanical polishing and reduce the risk of under-cleaning and/or over-cleaning of the surface of a wafer under the condition of precisely controlling the cleaning pressure of a cleaning brush assembly included in the cleaning device on different areas to be cleaned of the wafer. The cleaning device is applied to cleaning of wafers after chemical mechanical polishing, the wafers are provided with at least two areas to be cleaned, and the impurity distribution characteristics on the at least two areas to be cleaned are different. The cleaning device comprises a liquid supply unit, a liquid supply pipeline and a cleaning brush assembly. The liquid supply unit supplies cleaning liquid to the cleaning brush assembly through a liquid supply pipeline. The cleaning brush assembly is provided with at least two cleaning areas, and one cleaning area corresponds to one area to be cleaned. The liquid supply pipeline provides different cleaning forces for at least two cleaning areas. The invention also provides a cleaning system and a cleaning method.

Inventors

  • JIN TAIYUAN
  • ZHANG YUE
  • YANG TAO
  • LU YIHONG
  • LIU QING

Assignees

  • 中国科学院微电子研究所
  • 真芯(北京)半导体有限责任公司

Dates

Publication Date
20260508
Application Date
20201028

Claims (8)

  1. 1. The cleaning device is characterized by being applied to cleaning after polishing of a wafer, wherein the wafer is provided with at least two areas to be cleaned, and the impurity distribution characteristics on the at least two areas to be cleaned are different; the liquid supply unit supplies cleaning liquid to the cleaning brush assembly through the liquid supply pipeline; the cleaning brush assembly is provided with at least two cleaning areas, and one cleaning area corresponds to one area to be cleaned; the liquid supply pipeline provides different cleaning forces for at least two cleaning areas so that the cleaning pressures acting on the areas to be cleaned through the cleaning areas are different; The liquid supply pipeline comprises a liquid supply main pipeline communicated with the liquid supply unit and at least two liquid supply branches communicated with the liquid supply main pipeline, wherein at least one liquid supply branch is used for providing the cleaning liquid for one cleaning area; The cleaning brush assembly comprises a rotating shaft and a brush head sleeved on the rotating shaft; the rotary shaft is provided with a channel which is arranged along the axial direction of the rotary shaft and an injection port which is arranged along the radial direction of the rotary shaft, wherein the injection port is communicated with the channel; at least the liquid supply branch included in the liquid supply pipeline is arranged in the channel.
  2. 2. The cleaning apparatus defined in claim 1, wherein each of the fluid supply branches has at least one flow control valve thereon.
  3. 3. A cleaning system, comprising: the communication unit is used for acquiring impurity distribution characteristic information of the surface of the wafer; the processing unit is in communication connection with the communication unit, and determines a region to be cleaned of the surface of the wafer and a cleaning pressure control signal required by the region to be cleaned according to the impurity distribution characteristic information of the surface of the wafer; and the cleaning device of claim 1 or 2, which is communicatively connected to the communication unit.
  4. 4. The cleaning system of claim 3, wherein the cleaning system further comprises: The device comprises a communication unit, an information acquisition unit and a communication unit, wherein the communication unit is used for communicating the impurity distribution characteristic information of the surface of the wafer, and the information acquisition unit is used for communicating the impurity distribution characteristic information of the surface of the wafer.
  5. 5. A cleaning system according to claim 3, characterized in that the communication unit is further adapted to send a cleaning pressure control signal to the cleaning device, which provides the cleaning pressure to the cleaning zone under control of the cleaning pressure control signal, in case the cleaning pressure required for the zone to be cleaned is determined.
  6. 6. A cleaning method, comprising: acquiring impurity distribution characteristic information of the surface of the wafer; Determining a region to be cleaned of the surface of the wafer and cleaning pressure required by the region to be cleaned according to the impurity distribution characteristic information of the surface of the wafer, and determining a cleaning pressure control signal according to the cleaning pressure; Providing the cleaning pressure control signal to a cleaning device, wherein the cleaning device provides the required cleaning pressure for the area to be cleaned under the control of the cleaning pressure control signal, and the cleaning device is the cleaning device according to claim 1 or 2.
  7. 7. The cleaning method according to claim 6, wherein the impurity distribution characteristic information of the wafer surface includes impurity distribution thickness information, impurity distribution density information, and impurity type information.
  8. 8. The cleaning method of claim 6, wherein the cleaning pressure control signal is provided to a cleaning device that provides the desired cleaning pressure to the area to be cleaned under control of the cleaning pressure control signal, comprising: and controlling the flow rate of the cleaning liquid supplied by the liquid supply pipeline to a cleaning area of the cleaning brush assembly, wherein the cleaning area is opposite to the area to be cleaned.

Description

Cleaning device, cleaning system and cleaning method Technical Field The invention relates to the technical field of chemical mechanical polishing, in particular to a cleaning device, a cleaning system and a cleaning method. Background Chemical mechanical Polishing (CHEMICAL MECHANICAL Polishing, abbreviated CMP) is a surface global planarization technique. With the widespread use of chemical mechanical polishing in semiconductor device manufacturing processes, for example, CMP after forming an interlayer dielectric layer (ILD), CMP after forming a metal plug, CMP after forming a metal interconnect. post-CMP cleaning becomes particularly important. The main purpose of the post-CMP cleaning is to remove impurities such as abrasive particles, particles of the polished material, and chemical stains from the abrasive, etc., which are brought about in the CMP process. The cleaning methods provided by the related art generally comprise brush cleaning, acid spraying cleaning, megasonic cleaning and the like. Compared with other cleaning modes, the brush cleaning is widely applied due to the strong impurity removing capability and high efficiency. However, when the brush cleaning device provided by the related art is used for cleaning the surface of the wafer, there is a problem of under-cleaning and/or over-cleaning. Disclosure of Invention The invention aims to provide a cleaning device, a cleaning system and a cleaning method, which can reduce the risk of under-cleaning and/or over-cleaning of the surface of a wafer under the condition of precisely controlling the cleaning pressure of a cleaning brush assembly included in the cleaning device on different areas of the wafer to be cleaned. In order to achieve the above object, the present invention provides a cleaning device applied to cleaning after polishing a wafer, the wafer having at least two regions to be cleaned, the impurity distribution characteristics on the at least two regions to be cleaned being different. The cleaning device comprises a liquid supply unit, a liquid supply pipeline and a cleaning brush assembly. The liquid supply unit supplies cleaning liquid to the cleaning brush assembly through a liquid supply pipeline. The cleaning brush assembly is provided with at least two cleaning areas, and one cleaning area corresponds to one area to be cleaned. The liquid supply line provides different cleaning forces to at least two cleaning zones, so that the cleaning pressures acting on the areas to be cleaned through the cleaning zones are different. Compared with the prior art, when the cleaning device provided by the invention is applied to cleaning of the wafer after chemical mechanical polishing, under the condition that at least two areas to be cleaned are arranged on the surface of the wafer and the cleaning pressures required by the at least two areas to be cleaned are different, the accurate cleaning of different areas to be cleaned on the surface of the wafer can be realized by controlling the cleaning force provided by the liquid supply pipeline to the cleaning areas (corresponding to the areas to be cleaned in space) of the cleaning brush assembly. That is, when the cleaning pressure required for one of the areas to be cleaned on the surface of the wafer is large, the flow rate of the cleaning liquid supplied from the liquid supply line to the cleaning area (corresponding to the above-described area to be cleaned) provided in the cleaning brush assembly can be increased, and in the case where the flow rate of the cleaning liquid in the cleaning area is increased, the impact force of the cleaning liquid on the area to be cleaned can be increased to increase the cleaning pressure acting on the area to be cleaned provided in the wafer through the cleaning area. Based on the method, impurities on the to-be-cleaned area can be effectively removed, so that the risk of undercleaning on the to-be-cleaned area is reduced. When the cleaning pressure required by another area to be cleaned on the surface of the wafer is smaller, the flow rate of the cleaning liquid supplied by the liquid supply pipeline to the cleaning area (corresponding to the area to be cleaned) of the cleaning brush assembly can be reduced, and under the condition that the flow rate of the cleaning liquid in the cleaning area is reduced, the impact force of the cleaning liquid on the area to be cleaned can be reduced, so that the cleaning pressure acting on the area to be cleaned of the wafer through the cleaning area can be reduced. Based on this, the impurity on the above-mentioned area of waiting to wash of effective removal simultaneously, can also reduce the risk of the overcleaning that causes to above-mentioned area of waiting to wash. The invention also provides a cleaning system which comprises a communication unit for acquiring the impurity distribution characteristic information of the surface of the wafer. The processing unit is in communication with the communication un