그림자 효과 완화 및 내화학성 향상을 위한 탄탈륨-니켈 화합물 극자외선 흡수체

Abstract

Extreme ultraviolet lithography (EUVL) runs in reflective optics and the shadowing effect causes several new issues limiting the performance of EUV mask. To get over this shadowing effect, many studies are made by reducing the absorber thickness with high extinction coefficient materials. Nickel is a promising absorber material candidate which can replace tantalum compounds due to its high extinction coefficient. However, nickel is vulnerable to conventional mask cleaning process. In this paper, novel Ta-Ni compound material is fabricated by co-sputtering process and its improved chemical durability and shadowing effect is presented.