Patent ID: 7901849
Filing Date: 2011-03-08
Classification: G03F

Abstract:
1. A photomask, comprising: a light transmitting substrate; patterns disposed over the light transmitting substrate to define a light transmitting region of the substrate; and a light transmittance control layer disposed between the light transmitting substrate and the patterns, said control layer having a relatively high light transmittance in a first control layer region overlapping a first portion of the light transmitting region adjacent to a poor pattern having a size larger than a normal size, said control layer having a relatively low light transmittance in a second control layer region overlapping a second portion of the light transmitting region disposed between normal patterns having a normal size wherein the light transmitting control layer comprises a material having light transmittance that varies with an oxidation level of the material with a relatively high light transmittance in an oxidized portion of the layer compared to a non-oxidized portion of the layer.