A method is provided for patterning a target layer, the method comprising: (i) forming above the target layer a line mask and a mandrel mask, wherein forming the line mask comprises forming parallel material lines extending in a longitudinal direction, wherein forming the mandrel mask comprises forming a mandrel mask having sidewalls including at least a first sidewall extending transverse to a plurality of the material lines; (ii) forming on the sidewalls of the mandrel mask a sidewall spacer including a first sidewall spacer portion extending along the first sidewall; (iii) partially removing the sidewall spacer such that a remainder of the sidewall spacer comprises at least a part of the first sidewall spacer portion; and (iv) subsequent to removing the mandrel mask, transferring into the target layer a pattern defined by the line mask and the remainder of the sidewall spacer.