[18a-P06-1~19] 13.7 Compound and power devices, process technology and characterization

[18a-P06-13] Mist Chemical Vapor Deposited Alloy Gate Dielectric for Potential Applications in GaN Based MIS Devices

〇Hiroshi Otake¹, Yusui Nakamura¹, Zenji Yatabe¹ (1.Kumamoto Univ.)

Keywords:

mist-CVD,GaN,AlTiO

This study focused on characterization Al_1−xTi_xO_y alloy gate insulator films using mist CVD. Al_1−xTi_xO_y alloy films are promising as gate insulators for GaN-based MIS devices due to their wide bandgap and high permittivity. When the deposition temperature was varied from 250-450 ℃, the bandgap increased with increasing deposition temperature. XRF measurements suggested that the composition ratio could change with the deposition temperature. The reason why the composition ratio changes with deposition temperature is thought to be due to the temperature dependence of the deposition rate of Al₂O₃ and TiO₂.