US 12,066,765 B2
Operating method for preventing photomask particulate contamination
Jui-Chieh Chen, Hsinchu (TW); Tsung-Chih Chien, Nantou County (TW); Chih-Tsung Shih, Hsinchu (TW); and Tsung-Chuan Lee, Taipei (TW)
Assigned to TAIWAN SEMICONDUCTOR MANUFACTURING CO., LTD., Hsinchu (TW)
Filed by TAIWAN SEMICONDUCTOR MANUFACTURING CO., LTD., Hsinchu (TW)
Filed on Nov. 16, 2022, as Appl. No. 17/988,432.
Application 17/988,432 is a continuation of application No. 16/396,911, filed on Apr. 29, 2019, granted, now 11,506,985.
Prior Publication US 2023/0073062 A1, Mar. 9, 2023
Int. Cl. G03F 7/00 (2006.01); G03F 1/66 (2012.01)
CPC G03F 7/70708 (2013.01) [G03F 1/66 (2013.01); G03F 7/70916 (2013.01)] 20 Claims
OG exemplary drawing
 
1. A method, comprising:
securing a photomask on a bottom surface of an electrostatic chuck;
generating a first voltage at a peripheral area of the bottom surface of the electrostatic chuck to attract a particle onto the peripheral area of the bottom surface of the electrostatic chuck in a direction to the bottom surface of the electrostatic chuck, wherein the peripheral area of the bottom surface of the electrostatic chuck is not directly above the photomask;
after generating the first voltage, generating a second voltage at the peripheral area of the bottom surface of the electrostatic chuck to repulse the particle, wherein the first voltage and the second voltage have opposite electrical properties; and
generating a third voltage, by using a collecting plate, near a sidewall of the photomask to attract the repulsed particle.