Low temperature epitaxy of a semiconductor alloy including silicon and germanium employing a high order silane precursor

摘要

A high order silane having a formula of SinH2n+2, in which n is an integer greater than 3, in combination with a germanium precursor gas is employed to deposit an epitaxial semiconductor alloy material including at least silicon and germanium on a single crystalline surface. The germanium precursor gas effectively reduces the gas phase reaction of the high order silane, thereby improving the thickness uniformity of the deposited epitaxial semiconductor alloy material. The combination of the high order silane and the germanium precursor gas provides a high deposition rate in the Frank-van der Merwe growth mode for deposition of a single crystalline semiconductor alloy material.

主权项

1. A method of depositing a semiconductor alloy material including at least silicon and germanium comprising performing cycles of alternating deposition steps and etch steps, wherein each of said deposition steps deposits a semiconductor alloy material including at least silicon and germanium on a substrate by flowing a high order silane gas having a chemical formula of SinH2n+2 and a germanium precursor gas as reactant gases into a process chamber including said substrate, wherein n is an integer greater than 3, and each of said etch steps etches at least a portion of said deposited semiconductor alloy material by flowing a combination of a hydrogen chloride gas and a germanium-containing gas into said process chamber.