Patent ID: 9604314
Date: 2017-03-28
CPC Classifications: B23K,G03F,H01L

Claim:
1. A method of forming a pattern on a mask sheet using a laser beam, the method comprising: determining a target scan line with respect to the mask sheet, which corresponds to a position of the pattern on a final mask sheet; determining a correction scan line with respect to the mask sheet, along which the laser beam is scanned to form the pattern of the final mask sheet; applying a counter force to the mask sheet; fixing the mask sheet onto a mask frame while the counter force is applied to the mask sheet; scanning the laser beam along the correction scan line; and releasing the counter force which is applied to the mask sheet; the determining the correction scan line of the laser beam includes: applying a counter force to a preparatory mask sheet; fixing the preparatory mask sheet to a preparatory mask frame while the counter force is applied to the preparatory mask sheet; scanning the laser beam along the target scan line; releasing the counter force which is applied to the preparatory mask sheet; determining an actual scan line of the laser, in a status when the counter force which is applied to the preparatory mask sheet is released; determining an error between the target scan line and the actual scan line of the laser beam; and setting the correction scan line of the laser beam using the error.