Damascene extreme ultraviolet lithography alternative phase shift photomask and method of making

A photolithography mask comprising:

• a pattern layer selectively formed on a substrate in a photomask pattern;
• a multilayer stack formed on said pattern layer and said substrate comprised of a plurality of pairs of thin films;
• and
• an absorptive layer disposed in trenches formed within said multilayer stack, said absorptive layer being substantially absorptive of an EUV illuminating radiation, said trenches being located substantially over the borders between said pattern layer and said substrate.

A method for forming a photolithography mask comprising:

• providing a pattern layer selectively disposed upon a substrate, said pattern layer in a photomask pattern;
• forming over said pattern layer and said substrate a multilayer stack comprised of a plurality of pairs of thin films;
• forming a supplemental multilayer stack on said multilayer stack;
• patterning and etching trenches in said supplemental multilayer stack, said trenches being located substantially over the borders between said pattern layer and said substrate;
• and
• forming an absorptive layer into said trenches, said absorptive layer being substantially absorptive of an EUV illuminating radiation.

A photolithography mask for use with extreme ultraviolet lithography (EUVL) that uses extreme ultraviolet (EUV) illuminating radiation, said mask comprising:

• a substrate having recesses etched therein to form a photomask pattern;
• a multilayer stack formed over said recesses and said substrate that is substantially reflective of said EUV illuminating radiation;
• a supplemental multilayer stack formed atop said multilayer stack;
• and
• an absorber material formed in trenches patterned into said supplemental multilayer stack, said absorber material being substantially absorptive of said EUV illuminating radiation, said trenches being located substantially over the borders between said recesses and said substrate.

A method for forming a photolithography mask comprising:

• selectively etching a substrate such that recesses are formed, said recesses in a photomask pattern;
• forming over said recesses and said substrate a multilayer stack comprised of a plurality of pairs of thin films;
• forming a supplemental multilayer stack on said multilayer stack;
• patterning and etching trenches in said supplemental multilayer stack, said trenches being located substantially over the borders between said recesses and said substrate;
• and
• forming an absorptive layer into said trenches, said absorptive layer being substantially absorptive of an EUV illuminating radiation.