
TFT-LCD Photomask market. Photomask consists of a fused silica (QZ) or, glass (SL) substrate coated with an opaque film, in to which an accurate replication of the device designer's pattern is etched. Photomask has a similar function as a film used in photography. Just like the identical pictures are printed from the film, photomask can reproduce thousands of circuits and patterns. The photolithography technique is employed in the photomask manufacturing process to create chrome pattern on a quartz substrate. The finished photomask is then used as photographic plates for LSI, LCD, PCB, etc.