Mask for lithographic patterning and a method of manufacturing the same

Claim 1

A method of manufacturing a mask for electron beam lithographic patterning, comprising the steps of: joining a lower major surface of a silicon substrate having upper and lower major surfaces to a top side of a silicon oxide base body; reducing a thickness of said silicon substrate joined to said base body by polishing said upper major surface of said silicon substrate such that said silicon substrate has a reduced and uniform thickness which is smaller than about 20 μm but is large enough for interrupting an electron beam; patterning said silicon substrate to from a mask pattern region in said silicon substrate by forming apertures in said mask pattern region to define a plurality of mask patterns; and etching said base body such that a part of said base body located under said mask pattern region is removed, said step of etching being continued until portions of said lower major surface of said silicon substrate that are in said mask pattern region and that surround said apertures are completely exposed.

Claim 2

A method of manufacturing a mask for electron beam lithographic patterning, comprising the steps of: joining a lower major surface of a silicon substrate having upper and lower major surfaces to a top side of a silicon oxide base body; reducing a thickness of said silicon substrate joined to said base body by polishing said upper major surface of said silicon substrate such that said silicon substrate has a reduced and uniform thickness which is smaller than about 20 μm but is large enough for interrupting an electron beam; patterning said silicon substrate to from a mask pattern region in said silicon substrate by forming apertures in said mask pattern region to define a plurality of mask patterns; and etching said base body such that a part of said base body located under said mask pattern region is removed, said step of etching being continued until portions of said lower major surface of said silicon substrate that are in said mask pattern region and that surround said apertures are completely exposed.

Claim 6

A method of manufacturing a mask for electron beam lithographic patterning, comprising the steps of: joining a lower major surface of a silicon substrate having upper and lower major surfaces to an upper major surface of a base body having upper and lower major surfaces, said base body comprising a silicon oxide layer having upper and lower major surfaces and a base part having upper and lower major surfaces, said upper major surface of said base part being in contact with said lower major surface of said silicon oxide layer, said upper major surface of said silicon oxide layer being coincident with said upper major surface of said base body, and said lower major surface of said base part being coincident with said lower major surface of said base body; reducing a thickness of said silicon substrate joined to said base body by polishing said upper major surface of said silicon substrate such that said silicon substrate has a reduced and uniform thickness which is smaller than about 20 μm but is large enough for interrupting an electron beam; patterning said silicon substrate to form a mask pattern region in said silicon substrate by forming apertures in said mask pattern region to define a plurality of mask patterns; and etching said base body such that a part of said base body located under said mask pattern region is removed, said step of etching including a first step of etching said base body starting from said lower major surface of said base part to expose said lower major surface of said silicon oxide layer and a second step of selectively etching said silicon oxide layer starting from said exposed lower major surface of said silicon oxide layer until portions of said lower major surface of said silicon substrate that are in said mask pattern region and that surround said apertures are completely exposed.

Claim 7

A method of manufacturing a mask for electron beam lithographic patterning, comprising the steps of: joining a lower major surface of a silicon substrate having upper and lower major surfaces to an upper major surface of a base body having upper and lower major surfaces, said base body comprising a silicon oxide layer having upper and lower major surfaces and a base part having upper and lower major surfaces, said upper major surface of said base part being in contact with said lower major surface of said silicon oxide layer, said upper major surface of said silicon oxide layer being coincident with said upper major surface of said base body, and said lower major surface of said base part being coincident with said lower major surface of said base body; reducing a thickness of said silicon substrate joined to said base body by polishing said upper major surface of said silicon substrate such that said silicon substrate has a reduced and uniform thickness which is smaller than about 20 μm but is large enough for interrupting an electron beam; patterning said silicon substrate to form a mask pattern region in said silicon substrate by forming apertures in said mask pattern region to define a plurality of mask patterns; and etching said base body such that a part of said base body located under said mask pattern region is removed, said step of etching including a first step of etching said base body starting from said lower major surface of said base part to expose said lower major surface of said silicon oxide layer and a second step of selectively etching said silicon oxide layer starting from said exposed lower major surface of said silicon oxide layer until portions of said lower major surface of said silicon substrate that are in said mask pattern region and that surround said apertures are completely exposed.