Patent ID: 9362290
Filing Date: 2016-06-07
CPC Classification: G11C,H01L

Claim Text:
1. A method for manufacturing an SRAM, the method comprising: receiving a substrate; forming a first dummy pattern and a second dummy pattern adjacent to the first dummy pattern over the substrate, wherein the first dummy pattern has a first width and the second dummy pattern has the first width; forming a first spacer along a first sidewall of the first dummy pattern; forming a second spacer along a second sidewall of the first dummy pattern, wherein the second sidewall is opposite to the first sidewall; removing the first dummy pattern; forming a first fin of the SRAM by removing first portions of the substrate uncovered by the first spacer and forming a second fin of the SRAM by removing second portions of the substrate uncovered by the second spacer, wherein the forming the second fin is performed by a first patterning, wherein the removing first portions of the substrate and the removing second portions of the substrate are performed with the first spacer and the second spacer over the substrate, wherein the first spacer is a top-most mask over the substrate during the forming the first fin; removing the first spacer from a top surface of the first fin such that the top surface and sidewalls of the first fin are exposed, the top surface comprising semiconductor material; performing an additional patterning on the second fin such that the second fin has a shorter length than the first fin; and forming a first pull-down channel region in the first fin and a first pull-up channel region in the second fin.