| 摘要 |
Aluminium nitride, A1N, layers are grown on silicon substrate (12) using molecular beam epitaxial (MBE) growth. The A1N layer is initially grown by subjecting the silicon substrate to background ammonia followed by repetitively alternating the flux of 1) Al (22) without ammonia (27) and 2) ammonia without Al. After the surface of the silicon structure is sufficiently covered with AlN, the substrate is subjected to flux of ammonia and aluminium applied simultaneously to continue the epitaxial growth process. The process minimizes the formation of amorphous silicon nitride, SiN, compounds on the surface of the substrate which form due to background nitrogen levels in the molecular beam epitaxial growth apparatus. A surface free of amorphous silicon nitirde is necessary for the formation of high quality AlN. The AlN layer may be further used as abuffer layer for AlGaN/GaN growth. After the AlN layer (30) is grown on the silicon substrate, the silicon structure may be subjected to a flux of Ga and nitrogen to form a layer of GaN (40).
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