Lam Research Corporation
SELECTIVELY ETCHING FOR NANOWIRES

Abstract:

A method for selectively etching layers of a first material with respect to layers of a second material in a stack is provided. The layers of the first material are partially etched with respect to the layers of the second material. A deposition layer is selectively deposited on the stack, wherein portions of the deposition layer covering the layers of the second material are thicker than portions covering the layers of the first material, the selective depositing comprising providing a first reactant, purging some of the first reactant, wherein some undeposited first reactant is not purged, and providing a second reactant, wherein the undeposited first reactant combines with the second reactant and selectively deposits on the layers of the second material with respect to the layers of the first material. The layers of the first material are selectively etched with respect to the layers of the second material.