Silicon germanium (SiGe) is a semiconductor material that has a band gap that is smaller than that of silicon and which can be controlled by varying the germanium content. In recent years, the use of silicon germanium for advanced metal oxide semiconductor field effect transistor (MOSFET) devices has been widely investigated. Silicon germanium used in combination with silicon produces a heterojunction that provides for a transistor device having a low junction leakage and high mobility. Such high mobility is attractive in high speed devices, for example.