This project explores the potential of narrow bandgap semiconductors such as rhenium(Rh) molybdenum(Mo) silicide for use as a silicon microelectronics compatible wavelength adjustable infrared sensitive detector material. Determining the compositional (Rh, Mo) dependence of the bandgap value, and the influence of epitaxial crystal growth parameters on the microstructure of the films are major goals. Thin films of Rh and Mo will be deposited in stoichiometric proportions by e-beam evaporation onto silicon substrates. Silicide formation will be completed through thermally driven solid state reactions by two distinct modes--reactive deposition epitaxy, and solid phase epitaxy. The films will be evaluated by electron and x-ray spectroscopies, and the type of bandgap and its value will be determined by comparing optical data to theoretical models. This work, by providing information on fundamental materials synthesis, processing, and physical properties, is expected to lay the foundation for development of monolithically integrated silicon based intrinsic infrared detector prototypes suitable for use in the 8-14 micron wavelength range.
