Patent ID: 9558944
Date: 2017-01-31
CPC Classifications: G03F,H01L

Claim:
1. A method for patterning a semiconductor device in an extreme ultraviolet (EUV) lithography apparatus, said method comprising: providing an EUV lithography apparatus with an EUV radiation source; providing a substrate to be patterned, on a stage in said EUV lithography apparatus, said substrate coated with photoresist; positioning a reticle having a pattern side in confronting relation with said coated substrate; and directing a light beam from said EUV radiation source, to said pattern side at an oblique angle such that said light beam reflects off said reticle and onto said coated semiconductor substrate coated with photoresist, wherein said reticle includes a back side opposite the patterned side and includes a base material having a trench formed in said base material at an interface between an image field and an opaque border of said reticle or in said opaque border, said trench extending inwardly from said pattern side and having an absorber material along sidewalls and a bottom of said trench.