Four stages of research in the development of III.V semiconducting thin film materials bonded to polycrystalline or amorphous substrates are presented. First, new chemical vapor deposition (CVD) source materials for the deposition of III.V semiconducting thin films, such as gallium arsenide, indium phosphide and aluminum gallium arsenide, will be developed. These new source materials will be designed to display enhanced properties for CVD with the aid of theoretical calculations. Each new source materials will be synthesized, isolated, purified and characterized using standard chemical techniques. Second, the new source materials prepared in the first stage will be evaluated for use in CVD processes. Photolytic, pyrolytic and electron.assisted deposition techniques will be initially investigated for the formation of desired thin film materials from each new source compound. The decomposition (fragmentation) thermodynamics for each compound will also be studied using electron impact mass spectroscopy (through the use of appearance potential calculations). Third, studies will be initiated in which monocrystalline GaAs,InP and AlxGa1.xAs will be deposited on amorphous or polycrystalline ceramic substrates using a combination of graphoepitaxial and CVD techniques. Finally, attempts will be made to deposit patterned thin films of an appropriate material on the ceramic.supported III.V semiconductor to demonstrate potential application of these new materials to device technology and engineering. This research has important implications for the improved fabrication and operation of both microelectronic and optoelectronic devices.