Patent ID: 6994940
Filing Date: 2006-02-07
Classification: G03F

Abstract:
1. A phase shift mask comprising: a substrate made of a material transmitting exposure light; and a half tone light blocking film formed on said substrate and having an aperture exposing a portion of the surface of said substrate, wherein the phase of the exposure light transmitted through said halftone light blocking film differs from the phase of the exposure light transmitted through said aperture, the light transmission rate defined by the ratio of the light intensity of the exposure light transmitted through said half tone light blocking film to the light intensity of the exposure light transmitted through said aperture is not less than 15% to not more than 25%, and the dimension of said aperture is not less than 0.26 to not more than 0.45 on the basis of the measurement that exposure light wavelength λ/numerical aperture NA is set at 1.