The material of synthesized quartz is used to improve transmittance in maximum without any loss in the manufacturing of photo mask that is used to block light optionally in the exposure process among semiconductor LCD manufacturing. As a general manufacturing process of Photo Mask, Blank Mask is first preceded and then CrPatterning Patterning is done. The step of Blank Mask manufacturing is as follows.



The purpose of chemical etching is to remove micro crack damage of 20~40㎛ thickness in the mechanical lapping processing, and it is required to keep strict quality of 3 dimensional flatness, TTV(Total Thickness Variance), roughness in etching process. The result of applying new GLET solution after blank mask lapping is done, it was verified that 3 dimensional flatness, TTV, roughness were improved. Currently GLET solution is applied as etching solution to make mass production for generation 6, 7 large-sized TFT-LCD photo mask. Below table is quality comparison of surface after mask etching is done by using HF 5% solution and GLET solution.