While GaAs and other III-V compound semiconductors have many desirable properties, their practical use has been limited by the poor electrical quality of their surfaces and interfaces with other materials. For example, in contrast to the electronic perfection of the si-sio2 interface, the formation of oxides on GaAs results in a high density of surface states that effectively pin the surface Fermi level at the midgap, causing a high surface recombination velocity.Because of this, devices such as MISFETs have yet to be fully realized on GaAs, and the performance of devices sensitive to surface recombination is hindered. Since the incorporation of any passivation stage within the growth of the device structure is particularly desirable, MOCVD offers an attractive candidate for in-situ passivating layer growth. It is the goal of this work to develop GaS technology for MOCVD passivation of III-V devices as an integral part of device manufacture. In addition, new passivating materials will be developed for III-V compound semiconductors other than GaAs.Commercial Applications:Upon the completion of Phase I, Gallia will have the potential of a new product, GaS thin films as passivation materials; and a new process, passivation layers by MOCVD. The project will have immediate and significant technological applications in the general area of gallium arsenide devices.