causing a self - assemblable block copolymer having first and second blocks to migrate from a region surrounding a lithography recess of the substrate and a dummy recess on the substrate to within the lithography recess and the dummy recess , causing the bcp to self - assemble into an ordered layer within the lithography recess , the layer having a first block domain and a second block domain , and selectively removing the first domain to form a lithography feature having the second domain within the lithography recess , wherein a width of the dummy recess is smaller than the minimum width required by the bcp to self - assemble , the dummy recess is within the region of the substrate surrounding the lithography recess from which the bcp is caused to migrate , and the width between portions of a side - wall of the lithography recess is greater than the width between portions of a side - wall of the dummy recess .