THE NITRIDATION OF GAAS AND GAN DEPOSITION ON GAAS EXAMINED BY IN-SITU TIME-OF-FLIGHT LOW-ENERGY ION-SCATTERING AND RHEED

The growth of GaN on traditional zincblende III-V semiconductors such as GaAs is important technologically. Due to the high lattice mismatch between GaAs and III-V nitrides, the use of a buffer layer is always required. This can be achieved through either a low temperature buffer , a strained superlattice, or nitridation of GaAs surfaces by electron cyclotron resonance (ECR) bombardment. While this last process was sh own to improve the electrical and optical properties of the nitride th in films, no detailed investigation of the nitridation process has bee n reported. In this work, in situ time-of-flight low energy ion scatte ring (TOF-LEIS) and reflection high energy electron diffraction (RHEED ) are used to monitor surface structure, major elements, and impuritie s during the nitridation of GaAs as a function of time, temperature, a nd ECR power.