title: Fabry-perot-type antireflective coating for deep-ultraviolet binary photomask applications.
abstract: We demonstrate an antireflective coating structure, which is based on the three-layer metal interference called the Fabry-Perot structure, for a deep-ultraviolet binary mask. The antireflective coating structure is composed of a metal-oxide-metal stack. By addition of different optimized structures, reflectances of less than 1.5% at both 248 and 193 nm have been achieved. At the three-layer Fabry-Perot structure, the bottom chrome layer provides suitable absorption. By controlling the thickness of the intermediate silicon oxide layer, we can tune the minimum-reflection regime to the desired exposure wavelength. The top metal layer can prevent charge accumulation during e-beam writing.
authors.affiliation: National Nano Device Laboratory, Hsinchu, Taiwan. hlchen@ndl.gov.tw
authors.forename: Hsuen-Li
authors.initials: HL
authors.lastname: Chen
authors.forename: Tieh-Chi
authors.initials: TC
authors.lastname: Chu
authors.forename: Chien-Kui
authors.initials: CK
authors.lastname: Hsu
authors.forename: Fu-Hsiang
authors.initials: FH
authors.lastname: Ko
authors.forename: Tiao-Yuan
authors.initials: TY
authors.lastname: Huang