Patent ID: 9252021
Filing Date: 2016-02-02
CPC Classification: H01L

Claim Text:
1. A method of forming a non-rectangular pattern defined by an outer boundary, the method comprising: providing a semiconductor substrate; forming a plurality of elongated protrusions on the semiconductor substrate, the elongated protrusions extending in a first direction; forming a mask covering a first portion of the elongated protrusions, the mask being formed of a first material having a first etch rate; forming a spacer surrounding the mask, the spacer being formed of a second material with an etch rate lower than the etch rate of the first material, the mask and the spacer together covering a second portion of the elongated protrusions larger than the first portion of the elongated protrusions, and wherein an outer boundary of the spacer corresponds to the outer boundary of the non-rectangular pattern; and removing a remaining portion of the plurality of elongated protrusions not covered by the mask and spacer.