MOLECULAR-BEAM EPITAXY OF GALLIUM NITRIDE BY ELECTRON-CYCLOTRON-RESONANCE PLASMA AND HYDROGEN AZIDE

GaN films were grown on (0001) sapphire by molecular beam epitaxy (MBE). Two sources of activated nitrogen were investigated: an electron cyclotron resonance (ECR) plasma, and hydrogen azide (HN,). With the ECR plasma source, typical growth rates were similar to 0.1 mu m/h. Films grown in this manner showed significant surface damage from ions, and little if any photoluminescence. With HN3, growth rates were similar to 0.25 mu m/h. Azide-grown films showed smooth surfaces, and sharp band-to-band photoluminescence. This is the first reported use of HN3 to grow III-V nitrides by MBE, and it shows great promise as a nitrogen source.