AVS 45th International Symposium
    Selected Energy Epitaxy Topical Conference Thursday Sessions
       Session SE-ThM

Paper SE-ThM9
Defect-Driven Nucleation Kinetics of GaN Growth on Sapphire(0001)

Thursday, November 5, 1998, 11:00 am, Room 327

Session: In Situ Characterization and Real-Time Diagnostics of Surface Growth Processes
Presenter: A.R. Woll, Cornell University
Authors: A.R. Woll, Cornell University
J.D. Brock, Cornell University
R.L. Headrick, Cornell University
S. Kycia, Cornell University
Correspondent: Click to Email
Real-time, x-ray scattering techniques using the Cornell High Energy Synchrotron Source have been used to study the kinetics of GaN nucleation and growth on sapphire (0001) by RF plasma-assisted MOMBE. The initial growth rate of GaN, measured by gallium fluorescence, is observed to be highly nonlinear. The time to form the first bilayer was the same for substrates from the same wafer, but increased from 10 to 30 seconds on substrates with decreasing surface defect density, as indicated by x-ray measurements of surface quality. This suggests that the initial nucleation of GaN is defect-driven, perhaps occurring at steps on the surface. This work is supported by NSF Grant Nos DMR--9632275 (MSC) and DMR--9311772 (CHESS).