Patent ID: 6627356
Filing Date: 2003-09-30
Classification: G03F

Abstract:
A photomask, comprising:a transparent substrate having a first main surface and a second main surface opposite to said first main surface, said substrate transmitting exposed light; a pattern formed on said first main surface of said transparent substrate and having at least one of a translucent film and a phase control film, said translucent film transmitting partly said exposed light, and said phase control film serving to control the phase of the exposed light; and a film of a laminate structure formed on said second main surface of the transparent substrate and including at least a first thin film containing magnesium oxide and a second thin film containing magnesium fluoride, said first thin film being interposed between said second main surface and said second thin film, and the refractive coefficient of the first thin film being larger than the refractive coefficient of said second thin film; wherein said photomask meets the relationship of nf1&gE;nf2Ã—ns1/2, where ns represents the refractive coefficient of the transparent substrate relative to the wavelength of the exposed light, nf1 represents the refractive coefficient of the first film thin film, and nf2 represents the refractive coefficient of the second thin film.