Method using sub-micron silicide structures formed by direct-write electron beam lithography for fabricating masks for extreme ultra-violet and deep ultra-violet lithography

Abstract

To fabricate masks for deep ultra-violet lithography and for extreme ultra-violet lithography, a layer of material opaque to deep ultra-violet radiation and an extreme ultra-violet radiation absorbent layer are each deposited successively with a layer of silicon and a layer of metal on a respective transparent substrate. A focused electron beam is displaced on the superposed layers of metal and silicon to form a structure of etch-resistant metal/silicon compound. The deep ultra-violet mask is then formed by etching the three layers to leave on the substrate, the metal/silicon compound structure with the extreme ultra-violet absorbent layer beneath it. The extreme ultra-violet mask is fabricated by forming the absorbent layer successively of an etch-stop sublayer, a repair buffer sublayer, and a sublayer of extreme ultra-violet radiation absorbent material, which, after etching, leaves on the substrate, the metal/silicon compound structure with the extreme ultra-violet radiation absorbent sub-layer and the repair buffer sublayer beneath it.