One of the most promising applications of epitaxial III-V on Si materials technology is the monolithic integration of optoelectronic functions with Si integrated circuits. While simple implementations of this integrated technology have been demonstrated, there has been little attention paid to the types of heterostructures that are best suited for integration of GaAs and Si device functions from both material and device perspectives. The purpose of this program will be to develop a set of standard III-V heterostructure components that can be used as building blocks for lightwave applications, particularly optoelectronic integrated circuits, fabricated by epitaxial growth on large-area Si substrates using OMCVD. Phase I of this three phase program will determine the feasibility of such a technology through an evaluation of AlGaAs/GaAs epitaxial structures grown by OMCVD on Si substrates. The experimental structures will be representative of those needed for the fabrication of optical sources, detectors. waveguides, and modulators. The growth and properties of these structures will be investigated. Phase II will focus on the monolithic integration of these components on Si substrates. In particular, we will explore selective epitaxy to implement be integration of the different components. Phase III will focus on the commercialization of this device technology.