Abstract: Self-heating effects in traditional silicon-on-insulator （SOI） devices limit the applicability of SOI materials in power electronics. Instead of SiO₂, AlN as a buried insulator material in SOI-structure was investigated. Ion-beam-enhanced deposition was used to manufacture large area AlN films. Experimental results indicate that AlN film is obtained with best quality at the Al evaporation rate of 0.5 nm/s, it has excellent dielectric property and a smooth surface with roughness RMS valuesof 0.13 nm. New SOI structure with AlN film as buried insulator is manufactured successfully by the Smart-cut process. The observation of high-resolution TEM show that the new SOI structure can meet the requirements of device fabrication.