Patent ID: 9012328
Filing Date: 2015-04-21
Classification: H01L

Abstract:
1. A method of forming a layer on a substrate, comprising: forming a first epitaxial layer and a first silicon-containing layer on the substrate, the first epitaxial layer and the first silicon-containing layer comprising carbon and a first concentration of phosphorus; forming a second epitaxial layer over the first epitaxial layer and forming a second silicon-containing layer over the first silicon-containing layer, wherein the second epitaxial layer and the second silicon-containing layer are formed simultaneously, and each of the second epitaxial layer and the second silicon-containing layer comprises carbon and a second concentration of phosphorus less than the first concentration of phosphorus; and exposing the substrate to an etchant to completely remove the second epitaxial layer, the first silicon-containing layer, and the second silicon-containing layer.