Patent ID: 8669022

Claim:
A photomask for providing a photoresist layer disposed on a substrate with a predetermined photoresist pattern upon light exposure, the photoresist pattern having at least one first wiring region and at least one second wiring region, the first wiring region being larger in wiring density than the second wiring region, the photomask comprising: a transparent substrate; at least one first photomask pattern unit disposed on a surface of said transparent substrate for forming the first wiring region, and including a plurality of first light-blocking regions for blocking exposure light or for permitting passage of light energy lower than threshold energy of the photoresist layer, and a plurality of first light transmissive regions alternating with said first light-blocking regions for passage of exposure light; and at least one second photomask pattern unit disposed on a surface of said transparent substrate corresponding in position to the second wiring region, and including a plurality of second light-blocking regions for blocking exposure light or for permitting passage of light energy lower than threshold energy of the photoresist layer, and a plurality of second light transmissive regions alternating with said second light-blocking regions for pas sage of exposure light; wherein said first and second light-blocking regions differ in thickness.