Patent ID: 9684236
Date: 2017-06-20
CPC Classifications: B82Y,G03F,H01L

Claim:
1. A method comprising: forming a first patterned hard mask (HM) over a material layer, the first patterned hard mask defining an opening; forming a direct-self-assembly (DSA) layer by depositing a block co-polymer (BCP) layer over the first patterned HM and annealing the BCP layer at a first temperature, wherein the DSA layer has a first portion and a second portion within the opening; removing the first portion of the DSA layer; forming spacers along sidewalls of the second portion of the DSA layer; and removing the second portion of the DSA layer by annealing with a second temperature that is higher than the first temperature, resulting in the spacers forming a second patterned hard mask over the material layer.