Patent ID: 8889562

Claim:
A patterning method comprising: forming a first mask layer on a substrate; performing at least two dopant implantation processes using at least two additional mask layers to form, within said first mask layer, a doped region that comprises said dopant and that laterally surrounds multiple undoped regions, each undoped region having a shape with four sides and being laterally surrounded by said doped region such that each of said four sides is immediately adjacent to said doped region, said performing of said at least two dopant implantation processes using said at least two additional mask layers comprising: forming a second mask layer on said first mask layer, said second mask layer being patterned into a stripe mask pattern so that first portions of said first mask layer are exposed; doping said first portions with said dopant; removing said second mask layer; forming a third mask layer on said first mask layer, said third mask layer being patterned into an additional stripe mask pattern oriented at a different angle than said stripe mask pattern such that second portions of said first mask layer, which traverse said first portions, are exposed; doping said second portions with said dopant such that said first portions and said second portions in combination form said doped region that comprises said dopant and that laterally surrounds said multiple undoped regions; and, removing said third mask layer; selectively removing said doped region to form a mask pattern above said substrate; and, performing an etch process to transfer said mask pattern into said substrate to form multiple discrete features having said shape in said substrate, said dopant comprising phosphorous.