Patent ID: 7745909

Claim:
A semiconductor structure comprising: a substrate; an insulator layer on said substrate, said insulator layer covering said substrate and having a top surface; a first film above and in contact with said top surface of said insulator layer, wherein said first film comprises a first material; and a trench isolation region comprising: a trench extending vertically through said first film to said top surface of said insulator layer and separating said first film into a first portion and a second portion; and a second film within said trench above and in contact with said top surface of said insulator layer, wherein said second film extends laterally from said first portion of said first film to said second portion of said first film, wherein said second film comprises a second material that is different from said first material, and wherein said second film comprises a first section in contact with said first portion of said first film and having a first thickness and a second section in contact with said second portion of said first film and having a second thickness that is different from said first thickness, said first thickness and said second thickness being predetermined such that said first portion of said first film exhibits first reflectance and absorption characteristics and said second portion of said first film exhibits second reflectance and absorption characteristics that are selectively different from said first reflectance and absorption characteristics.