Patent ID: 11953839
Assignee: TAIWAN SEMICONDUCTOR MANUFACTURING COMPANY LTD.
Field: Optics (Instruments)
Classification: CPC G | IPC G

Claim 15:
16. A cleaning method, comprising:
directing a fan shape stream of gas to enter into a chamber of a wafer table of a lithography system;
rotating the fan shape stream of gas to sweep an area and to impinge onto walls and surfaces of one or more wafer chucks in the chamber to extract one or more particles from the walls and the surfaces of the one or more wafer chucks;
directing the entered gas and the extracted one or more particles as a first stream of gas to a gas filter system outside the chamber of the wafer table to clean the first stream of gas;
recycling the cleaned first stream of gas into the chamber of the wafer table when a number of particles in the first stream of gas is below a first threshold and an amount of organic material in the first stream of gas is below a second threshold; and
ending the first stream of gas when the number of particles in the first stream of gas continuously stays below the first threshold for a predetermined amount of time and the amount of organic material in the first stream of gas continuously stays below the second threshold for the predetermined amount of time.