AbstractEpitaxial GaAs films have been deposited on Si substrates using Atomic Layer Epitaxy (ALE) for the first time. This has been achieved in a SPI-MO CVD™ 450 reactor especially modified foroALE. After an initial high temperature bakeout, a nucleation layer 100-300 Å thick was deposited by ALE. Film growth was then resumed by conventional MOCVD to achieve the desired film thickness. The surface morphologies of the deposited films were found to be comparable to current state of the art conventional GaAs on Si films deposited by the two-step growth process in the same reactor.Selective area epitaxy of GaAs on Si has also been achieved on Si02-coated and patterned Si wafers. The standard two-step deposition technique resulted in epitaxial growth in the patterned windows and poly-GaAs on the oxide mask, while ALE growth resulted in deposition only in the etched windows with no poly-growth on the oxide mask. We will report on the potential of this new deposition technique in producing high quality GaAs-on-Si films.
