Patent ID: 9257280
Filing Date: 2016-02-09
CPC Classification: H01L

Claim Text:
1. A method for self-aligned pattern etching, the method comprising: providing a substrate having spacers formed on a sidewall of one or more mandrels, wherein the spacers are formed on an underlying layer, and the spacers are formed of a first material, and wherein the underlying layer is formed of a second material; removing the one or more mandrels, such that the resulting spacers have a cross sectional shape in which a first sidewall is relatively planar and a second sidewall, on an opposite side of a respective spacer, is faceted having a non-planar surface; etching a first portion of the underlying layer using the spacers as a mask; depositing or growing a protective layer on sidewalls of the underlying layer created during etching of the first portion; and etching a remaining portion of the underlying layer using the spacers as a mask; wherein the etching of the first portion and the etching of the second portion are performed by plasma etching; wherein etching is stopped during the depositing or growing of the protective layer; wherein during the depositing or growing of the protective layer upon the sidewalls that are formed during the etching of the first portion, the protective layer is also deposited on a bottom wall of the underlying layer, and wherein the method further comprises performing a breakthrough etch to etch through the protective layer on the bottom wall of the underlying layer; and wherein during the breakthrough etch, both: