Patent ID: 9305845
Filing Date: 2016-04-05
CPC Classification: H01L,Y10S

Claim Text:
1. A method of forming a mandrel structure comprising: forming a plurality of first mandrel structures comprising a neighboring pair of first mandrel structures on a surface of a substrate; forming an additive mask on facing sidewall surfaces of said neighboring pair of first mandrel structures and on said surface of said substrate that is located between said neighboring pair of first mandrel structures; forming a first spacer on said additive mask and exposed surfaces of each first mandrel structure and said exposed surfaces of said substrate; removing portions of each first spacer and said additive mask to provide a first set of second mandrel structures having a first width on said facing sidewall surfaces of said neighboring pair of first mandrel structures and a second set of second mandrel structures having a second width that is less than said first width on non-facing sidewall surfaces of said neighboring pair of first mandrel structures; removing each first mandrel structure; forming a second spacer on a sidewall surface of said first and second sets of second mandrel structures, wherein in a region between said neighboring pair of first mandrel structures a merged spacer is formed; removing said first and second sets of second mandrel structures; and patterning a portion of said substrate utilizing said second spacer and said merged spacer as etch masks.