SELF-ALIGNED NANOWIRE FORMATION USING DOUBLE PATTERNING

摘要

A method comprises forming a pattern-reservation layer above a semiconductor substrate. The semiconductor substrate has a major surface. A first self-aligned multi-patterning process is performed to pattern a pattern-reservation layer. The remaining portions of the pattern-reservation layer comprise pattern-reservation strips extended in a first direction which is in parallel to the major surface of the semiconductor substrate. A second self-aligned multi-patterning process is performed to pattern the pattern-reservation layer in a second direction which is in parallel to the major surface of the semiconductor substrate. The remaining portions of the pattern-reservation layer comprise patterned features. The patterned features are used as an etching mask to form semiconductor nanowires by etching the semiconductor substrate.