This paper describes preliminary device work on GexSi1−x, based devices and examines progress towards the realization of a silicon based heterostructure technology. Target areas for further work are identified including: An enhanced understanding of metastable-growth processes; The need for defect confinement in discommensurate epitaxy; Elimination of manufacturing barriers caused by particulate induced defects in MBE and low growth rates in low temperature CVD.
Over the last five years, studies of GexSi1−x have yielded an understanding of crystal growth mechanisms and information on electrical and optical properties such as bandstructure and heterojunction band alignment. These in turn lead to a number of preliminary device applications including optical detectors, modulation doped transistors and heterojunction bipolar transistors. In this paper, I will try to answer the question posed by the symposium organizers: In the germanium silicide system, has our understanding and experience reached the point that we have the basis for a technology, and if not, where must further work be done?