Photomask blank and production method thereof, and photomask production method, and semiconductor device production method

Abstract

A photomask blank which is capable of preventing static buildup caused by electron beam pattern drawing for forming a resist pattern. The photomask blank provides a good pattern accuracy through optimization of the dry etching rate along the depth direction of the shielding film, and is capable of reducing the dry etching time by increasing the dry etching rate of the shielding film. The photomask blank includes a translucent substrate having thereon a shielding film composed mainly of chromium and the shielding film contains hydrogen. The shielding film is formed in such a manner that the film formation rate of the layer at the surface side is lower than the film formation rate of the layer at the translucent substrate side of the shielding film. The dry etching rate of the shielding film is lower at the translucent substrate side than at the surface side.