Low-temperature selective epitaxy contact approach

Abstract

Semiconductor devices and methods for manufacturing the same are provided. The method includes epitaxially growing a doped crystalline silicon-containing layer over a source/drain feature and growing a doped amorphous silicon-containing layer over a field region of a semiconductor layer. The trench is formed in the semiconductor layer and the trench exposes the source/drain feature. The method further includes epitaxially growing an undoped crystalline silicon-containing capping layer over the doped crystalline silicon-containing layer and growing an undoped amorphous silicon-containing layer over the doped silicon-containing amorphous layer. The method further includes selectively removing the doped amorphous silicon-containing layer and the undoped amorphous silicon-containing layer relative to the silicon-containing crystalline capping layer. The method further includes removing the silicon-containing crystalline capping layer to expose the doped silicon-containing crystalline layer.