Fundamental research to investigate the formation of silicide and silicide-germanide films on coherently strained Si and Si1-xGex films will be conducted. Special features of the research are the ability to alter film-substrate strain independently of film-substrate interfacial chemical composition; the direct correlation of strain, independent of chemical factors, with thermodynamic and electronic properties of the film-substrate couple; and, preliminary studies of the chemistry and physics of formation of silicide or silicide-germanide compounds from deposited metals reacted with Si1-xGexsubstrates. %%% This research is expected to provide deeper fundamental understanding of basic properties of thin films and interfaces critically important to the functionality of electronic/photonic materials and particular compositional and structural combinations and configurations relevant to devices and circuits. From an application point of view, understanding these properties and their relationship to materials synthesis and processing is highly beneficial to semiconductor device design and fabrication. The results will be of importance in a general way to the technology of large scale, high speed integrated electronic and photonic devices and circuits.