CN-122007095-A - Plasma in-situ cleaning method, equipment and storage medium

CN122007095ACN 122007095 ACN122007095 ACN 122007095ACN-122007095-A

Abstract

The application relates to the technical field of cleaning of heat treatment equipment, and particularly provides a plasma in-situ cleaning method, equipment and a storage medium, wherein the method comprises the steps of analyzing whether a heat treatment chamber needs to be cleaned according to the execution times of a heat treatment process after the last cleaning and pollutant parameter information; the method comprises the steps of determining gas supply flow, power supply working parameters, exhaust flow and single cleaning time according to historical heat treatment process types and pollutant parameter information, conveying cleaning gas into a heat treatment chamber according to the gas supply flow, starting to calculate the cleaning time after the pressure in the heat treatment chamber reaches a preset pressure range, controlling a pulse radio frequency power supply to provide a corresponding pulse signal for a radio frequency electrode according to the power supply working parameters so as to ionize the cleaning gas into plasma, controlling an exhaust assembly to work according to the exhaust flow so as to exhaust byproduct gas formed by the plasma and pollutants, and effectively reducing pollutant accumulation in the heat treatment chamber.

Inventors

DAI KEFENG
WU GUOFA
TAN YONGXIN
ZHANG NAN

Assignees

季华实验室

Dates

Publication Date: 20260512
Application Date: 20260415

Claims (10)

1. The in-situ plasma cleaning method is used for in-situ plasma cleaning of a heat treatment chamber and is characterized by being applied to a in-situ plasma cleaning system, wherein the in-situ plasma cleaning system comprises a plasma generation unit, a cleaning gas conveying component, a pollutant information acquisition component and an exhaust component, the plasma generation unit comprises a radio frequency electrode and a pulse radio frequency power supply, the pollutant information acquisition component is used for acquiring pollutant parameter information in the heat treatment chamber, and the in-situ plasma cleaning method comprises the following steps: S1, when the heat treatment process is not carried out on the heat treatment chamber, analyzing whether the heat treatment chamber needs to be cleaned according to the execution times of the heat treatment process after the previous cleaning and the pollutant parameter information, if so, executing the step S2, and if not, ending; s2, determining gas supply flow, power supply working parameters, exhaust flow and single cleaning duration according to the historical heat treatment process type and the pollutant parameter information; S3, controlling the cleaning gas conveying assembly to convey cleaning gas into the heat treatment chamber according to the gas supply flow; And S4, after the pressure in the heat treatment cavity reaches a preset pressure range, starting to calculate a cleaning time length, controlling the pulse radio frequency power supply to provide a corresponding pulse signal for the radio frequency electrode according to the power supply working parameter so as to ionize the cleaning gas into plasma, and controlling the exhaust assembly to work according to the exhaust flow so as to exhaust the by-product gas formed by the plasma and pollutants until the pollutant parameter information is smaller than or equal to a preset cleaning end threshold value or the cleaning time length reaches the single cleaning time length.
2. The plasma cleaning-in-place method of claim 1, wherein step S1 comprises: S11, when the heat treatment process is not carried out on the heat treatment chamber, obtaining process type information of the next heat treatment process to be executed; s12, determining the cleanliness requirement of the chamber according to the process type information; s13, determining a cleaning trigger threshold according to the chamber cleanliness requirement; S14, analyzing whether the execution times of the heat treatment process after the last cleaning reaches the preset times or the pollutant parameter information reaches the cleaning trigger threshold, if so, considering that the heat treatment chamber needs to be cleaned, executing the step S2, and if not, considering that the heat treatment chamber does not need to be cleaned, and ending.
3. The plasma cleaning-in-place method of claim 2, wherein step S13 comprises: s131, determining an initial trigger threshold according to the chamber cleanliness requirement; s132, obtaining process parameter information and material batch information of a next heat treatment process to be executed; s133, adjusting the initial trigger threshold according to the process parameter information and the material batch information, and taking the adjusted initial trigger threshold as a cleaning trigger threshold.
4. The plasma in-situ cleaning method of claim 2, wherein the contaminant parameter information includes particulate matter quantity information and concentration information corresponding to each component gas in the contaminated gas, the cleaning trigger threshold includes a first particulate matter quantity threshold and a first gas concentration threshold corresponding to each component gas, the cleaning end threshold includes a second particulate matter quantity threshold and a second gas concentration threshold corresponding to each component gas, and for the same component gas, the corresponding first particulate matter quantity threshold is greater than its corresponding second particulate matter quantity threshold, and the corresponding first gas concentration threshold is greater than its corresponding second gas concentration threshold.
5. The plasma cleaning-in-place method of claim 1, wherein step S2 comprises: s21, extracting corresponding supply flow as initial supply flow, corresponding power supply parameter as initial working parameter, corresponding exhaust quantity as initial exhaust quantity and corresponding cleaning time from a pre-constructed mapping relation table of executed process type and pollutant parameter combination and corresponding supply flow, power supply parameter, exhaust quantity and cleaning time according to historical heat treatment process type and pollutant parameter information; S22, acquiring a preset tolerance threshold value corresponding to each device in the heat treatment equipment; S23, adjusting the initial supply flow, the initial working parameters, the initial exhaust gas amount and the initial duration according to the minimum value of the preset tolerance threshold; S24, taking the adjusted initial supply flow as the gas supply flow, taking the adjusted initial working parameter as the power supply working parameter, taking the adjusted initial exhaust gas amount as the exhaust flow, and taking the adjusted initial duration as the single cleaning duration.
6. The plasma cleaning-in-place method of claim 5, wherein step S23 comprises: S231, acquiring accumulated running time and accumulated cleaning times of all devices in the heat treatment equipment; S232, determining the attenuation degree of each device in the heat treatment equipment according to the accumulated running time and the accumulated cleaning times corresponding to the device, and correcting the preset tolerance threshold corresponding to the device according to the attenuation degree to obtain the corrected tolerance threshold corresponding to the device; S233, adjusting the initial supply flow, the initial operating parameter, the initial exhaust gas amount and the initial duration according to the minimum value of the correction tolerance threshold.
7. The plasma cleaning-in-place method of claim 1, wherein step S4 comprises: S41, after the pressure in the heat treatment chamber reaches a preset pressure range, starting to calculate a cleaning time length, controlling the pulse radio frequency power supply to provide a corresponding pulse signal for the radio frequency electrode according to the power supply working parameter so as to ionize the cleaning gas into plasma, and controlling the exhaust assembly to work according to the exhaust flow so as to exhaust the byproduct gas formed by the plasma and pollutants; S42, when the pollutant parameter information is smaller than or equal to a preset cleaning end threshold, considering that in-situ cleaning is completed, controlling the pulse radio frequency power supply and the cleaning gas conveying assembly to stop working, and controlling the exhaust assembly to work until the pressure in the heat treatment cavity reaches a preset pressure threshold, wherein the preset pressure threshold is smaller than the lower limit value of the preset pressure range; S43, when the cleaning time length reaches the single cleaning time length and the pollutant parameter information is larger than the cleaning end threshold value, analyzing whether the actual cleaning times reach the preset times, if so, generating alarm information, otherwise, setting the cleaning time length to 0, and returning to the step S41.
8. The plasma cleaning-in-place method of claim 7, wherein step S4 further comprises the steps of: a1, continuously acquiring real-time temperature information of the heat treatment chamber in the cleaning process; A2, when the real-time temperature information is larger than a preset temperature threshold value, the duty ratio of the pulse radio frequency power supply is reduced according to the deviation between the real-time temperature information and the preset temperature threshold value.
9. An electronic device comprising a processor and a memory storing computer readable instructions that, when executed by the processor, perform the steps in the method of any of claims 1-8.
10. A computer readable storage medium, on which a computer program is stored, characterized in that the computer program, when being executed by a processor, performs the steps of the method according to any of claims 1-8.

Description

Plasma in-situ cleaning method, equipment and storage medium Technical Field The application relates to the technical field of cleaning of heat treatment equipment, in particular to a plasma in-situ cleaning method, equipment and a storage medium. Background Rapid Thermal Processing (RTP) equipment generally adopts a cold wall design structure, realizes rapid heating of a wafer by high-intensity lamp tube radiation, and simultaneously maintains a low-temperature state of a reaction cavity wall by a water cooling system. Although this design can effectively reduce the thermal mass, achieve rapid temperature rise and drop and avoid cavity thermal contamination, significant contamination problems are exposed during actual high temperature processes. When the process temperature exceeds 1000 ℃, trace water vapor, oxygen, metal impurities and other pollutants adsorbed on the inner wall surface of the chamber can be desorbed at high temperature due to the acquisition of enough energy, and are released into the process environment in a gaseous form. During the subsequent cool down phase, as the chamber wall temperature and wafer temperature drop simultaneously, these gaseous contaminants will recondense and randomly deposit on the wafer surface, forming surface contaminants that are difficult to detect and control. This cold wall redeposition phenomenon, which is caused by the cold wall effect, has become a key factor affecting the yield of semiconductor devices. The traditional cleaning method mainly adopts a periodic off-line cleaning mode, and has three main defects that firstly, a fixed cleaning period cannot adapt to pollutant differences generated by different processes, so that insufficient cleaning or excessive cleaning is caused, secondly, the off-line cleaning needs to interrupt the production flow, the equipment utilization rate is obviously reduced, and furthermore, the conventional cleaning parameter setting lacks dynamic response capability to the pollution characteristics of the historical process. In view of the above problems, no effective technical solution is currently available. Disclosure of Invention The application aims to provide a plasma in-situ cleaning method, equipment and a storage medium, which can effectively reduce pollutant accumulation in a heat treatment cavity. In a first aspect, the present application provides a plasma in-situ cleaning method for cleaning a thermal processing chamber in-situ, applied in a plasma in-situ cleaning system, the plasma in-situ cleaning system includes a plasma generating unit, a cleaning gas delivery assembly, a pollutant information acquisition assembly and an exhaust assembly, the plasma generating unit includes a radio frequency electrode and a pulsed radio frequency power supply, the pollutant information acquisition assembly is used for acquiring pollutant parameter information in the thermal processing chamber, the plasma in-situ cleaning method includes the following steps: s1, when the heat treatment process is not performed on the heat treatment chamber, analyzing whether the heat treatment chamber needs to be cleaned according to the execution times of the heat treatment process after the previous cleaning and pollutant parameter information, if so, executing the step S2, and if not, ending; S2, determining gas supply flow, power supply working parameters, exhaust flow and single cleaning duration according to the historical heat treatment process type and pollutant parameter information; S3, controlling the cleaning gas conveying assembly to convey the cleaning gas into the heat treatment chamber according to the gas supply flow; And S4, after the pressure in the heat treatment chamber reaches a preset pressure range, starting to calculate the cleaning time, controlling a pulse radio frequency power supply to provide a corresponding pulse signal for a radio frequency electrode according to a power supply working parameter so as to ionize cleaning gas into plasma, and controlling an exhaust assembly to work according to an exhaust flow so as to exhaust by-product gas formed by the plasma and pollutants until the pollutant parameter information is smaller than or equal to a preset cleaning end threshold value or the cleaning time reaches a single cleaning time. According to the plasma in-situ cleaning method provided by the application, through intelligent monitoring and dynamic adjustment of the cleaning process, the accumulation of pollutants in the heat treatment cavity is effectively reduced, so that the redeposition of the pollutants caused by the cold wall effect is prevented. Optionally, step S1 includes: S11, when the heat treatment process is not performed in the heat treatment chamber, obtaining process type information of the next heat treatment process to be performed; S12, determining the chamber cleanliness requirement according to the process type information; s13, determining a cleaning trigger threshold according to the ch