Method of forming a germanium film on a semiconductor substrate that includes the formation of a graded silicon-germanium buffer layer prior to the formation of a germanium layer

摘要

A composite of germanium film for a semiconductor device and methods of making the same. The method comprises growing a graded germanium film on a semiconductor substrate in a deposition chamber while simultaneously decreasing a deposition temperature and decreasing a silicon source gas and increasing a germanium source gas over a predetermined amount of time. The graded germanium film comprises an ultra-thin silicon-germanium buffer layer and a germanium film.