EXTREME ULTRA-VIOLET PHOTOLITHOGRAPHY MASK, WITH RESONANT BARRIER LAYER

摘要

The invention relates to extreme ultraviolet photolithography masks operating by reflection. These masks comprise a lower mirror (22) covering a substrate (20), and two types of reflecting zones (Z1 and Z2) to constitute a phase shifting mask. An etching barrier layer (23) is interposed between the lower mirror (22) and an upper reflecting structure (24). This layer has a thickness such that it behaves as a reflecting resonant cavity flanked by the upper (24) and lower (22) reflecting structures.