Extreme Ultraviolet Mask Blank Hard Mask Materials

An extreme ultraviolet (EUV) mask blank comprising:

• a substrate;
• a multilayer stack which reflects EUV radiation, the multilayer stack comprising a plurality of reflective layer pairs;
• a capping layer on the multilayer stack of reflecting layers;
• an absorber layer, the absorber layer comprising an antimony-containing material;
• and
• a hard mask layer on the absorber layer, the hard mask layer comprising a hard mask material selected from the group consisting of CrO, CrON, TaNi, TaRu and TaCu.

An extreme ultraviolet (EUV) mask blank comprising:

• a substrate;
• a multilayer stack which reflects EUV radiation, the multilayer stack comprising a plurality of reflective layer pairs including molybdenum (Mo) and silicon (Si);
• a capping layer on the multilayer stack of reflecting layers;
• an absorber layer, the absorber layer comprising an antimony-containing material selected from the group consisting of SbN, an alloy of carbon and antimony, and an alloy of tantalum and antimony;
• and
• a hard mask layer on the absorber layer, the hard mask layer comprising a hard mask material selected from the group consisting of CrO, CrON, TaNi, TaRu and TaCu, wherein the hard mask layer has an etch rate and the absorber layer has an etch rate such that there is an etch selectivity of the hard mask layer to the absorber layer is in a range of from 5:1 to 30:1.