Material properties of gan grown by radio frequency plasma-assisted molecular beam epitaxy on si

GaN films were grown on Si (1 11) substrates by nitrogen rf plasma source molecular beam epilaxy. Reflection high-energy diffraction (RHEED), atomic force inicroscopy, infrared transmittance and photoluminescence results characterized the properties of GaN f i l m grown under d$fireni in-situ substrate preparation and growth initiation methods. Very smooth surfaces, exhibiting surface recons~ruction in RHEED, were achieved by using an AlN buffer layer. However, these films produced weak photoluminescence, compared to that of the GaN layers directly deyosiied on a reconsiructed 7x7 Si (1 11) surface.