Patent ID: 7954340
Filing Date: 2011-06-07
Classification: C03B,C03C,Y02P

Abstract:
1. A method for preparing a synthetic quartz glass substrate for use with excimer lasers, comprising the steps of: (i) hot shaping a synthetic quartz glass ingot at a temperature in the range of 1700 to 1900° C. into a block of desired shape; (ii) annealing the synthetic quartz glass block at a temperature in the range of 1,000 to 1,300° C.; (iii) slicing the synthetic quartz glass block as annealed into a substrate of desired thickness; and (iv) polishing the sliced synthetic quartz glass substrate; and (v) heat treating the sliced synthetic quartz glass substrate at a temperature in the range of 700 to 1,300° C. in air or in an inert gas atmosphere for a time of 5 to 12 hours, and then irradiating ultraviolet radiation thereto for a time of 12 to 60 hours.