Half-tone stacked film, photomask-blank, photomask and fabrication method thereof

摘要

Ahalf-tone stacked film is designed so as to have a stacked structure of a first half-tone film (13) and a second half-tone film (14), and the film thickness d, the refractive index n to exposure light and the extinction coefficient k of these half-tone films are designed so that one of these half-tone films becomes a phase advancement film and the other becomes a phase retardation film. When the film thickness (nm), the refractive index, and the extinction coefficient of the phase advancement film are represented by d (+) , n (+) and k (+) , respectively; and the film thickness (nm), the refractive index, and the extinction coefficient of the phase retardation film are d (-) , n (-) , and k (-) , respectively; the phase advancement film has the relationship of k (+) > a 1 ·n (+) + b 1 , and the phase retardation film has the relationship of k (-) < a 2 ·n (-) + b 2 .