International Business Machines Corporation
DOUBLE PATTERNED LITHOGRAPHY USING SPACER ASSISTED CUTS FOR PATTERNING STEPS

Abstract:

A method includes forming a dielectric layer on a semiconductor substrate, forming a first mandrel layer and a second mandrel layer on the dielectric layer and patterning the first mandrel layer and the second mandrel layer to form respective first and second patterns in the first and second mandrel layers. The first pattern includes a first line segment and a first wing segment. The first wing segment is filled with a first spacer material to form a first spacer. The method further includes removing exposed portions of the first and second mandrel layers, transferring an image of the first and second patterns, patterning the dielectric layer and depositing a metal into the patterned dielectric layer to form a metallic interconnect structure. The metallic interconnect structure includes first and second metallic lines with the second metallic line having a line break corresponding to the first spacer.