progress on the columbia uri program on interfacial and thin film chemistry in electron device fabrication is reported for the 1986-1991 period. three broad areas of research included mbe growth and devices, laser surface interactions, and fundamentals of processing gas/surface interactions. research in the area of mbe growth and devices included heterostructures grown by molecular beam epitaxy by professor wen wang and interface chemical modification of metal on superconductor-semiconductor systems by professor ed yang research in the area of laser surface interactions included laser-surface interactions and in situ diagnostics of surface chemistry during electronic processing by professor richard osgood, jr.; in situ optical diagnostics of semiconductors prepared by laser chemical processing and other novel methods by professor irving herman; and ultrafast optoelectronic measurements of surfaces and interfaces by professor david auston. research in fundamentals of processing gas/surface interactions included quantum state-resolved studies of gas/surface chemical reactions by professor george flynn and photochemical and photophysical probes of interfaces by professor nicholas turro. research results of columbia's principal investigators supported by onr/uri were published in nearly 200 scholarly articles which are listed in this report. molecular beam epitaxy, strain, tunneling, chlorine atoms, chemical reactions, cold rotations, diode lasers, excimer lasers, electrons, collision dynamics, electron scattering, surfaces, bronsted acids, zeolites, heterostructures, optical m