Patent ID: 8216745

Claim:
A halftone mask including a glass substrate, the half tone mask comprising: a transparent portion using the glass substrate; a first semi-transparent portion including a first semi-transparent layer formed on the glass substrate; and a light shield portion including the first semi-transparent layer, a light shield layer superimposed above the first semi-transparent layer, and an etching stopper layer formed between the first semi-transparent layer and the light shield layer; wherein the first semi-transparent layer and the light shield layer are each formed from Cr or at least one selected from a group consisting of an oxide, nitride, carbide, oxynitride, oxycarbide, carbonitride, and oxycarbonitride of Cr; and the etching stopper layer includes a first element of at least one selected from a group consisting of Fe, Ni, and Co and a second element of at least one selected from a group consisting of Al, Si, Ti, Nb, Ta, Hf, and Zr.