Microstructures of AlGaN/AlN/Si (111) Grown by Metalorganic Chemical Vapor Deposition

In this paper the X-ray photoelectron spectrum and the Auger electron spectrum were used to study the microstructures of AlGaN/AlN/Si (111) grown by metal organic chemical vapor deposition. The results indicated that a broad transition region, about 20 nm, was present at the interface of AlN/Si and it was composed of AlN and SiNx (0 ≤ x ≤ 4/3). In AlN film the existence of Si–Si bonds was found. In the interface of AlGaN/AlN, the main incorporation form of N1s varied gradually from AlN to the compound of GaN and AlN The diffusion of Si atoms was so strong at the high growth temperatures that the signal of Si2p could be found throughout the epilayer.