This letter demonstrates an integration process of in situ Cl- doped Al2O3 and gate recess technique to fabricate the enhancement mode AlGaN/GaN MOSHEMTs. The Cl- doped Al2O3 thin film is deposited by the ultrasonic spray pyrolysis deposition and characterized by transmission electron microscopy and X-ray photoelectron spectroscopy. The relative permittivity of Cl- doped Al2O3 is higher than the pure Al2O3 and the output current is enhanced. The threshold voltage of the enhancement mode AlGaN/GaN MOSHEMT with the Cl- doped Al2O3 gate dielectric layer rose from 0.2 to 1.3 V. Furthermore, the breakdown voltage of present enhancement mode AlGaN/GaN MOSHEMT reached 650 V. It was also found that the MOSHEMT with Cl- doped Al2O3 has higher gate leakage than that with pure Al2O3. The thermal stability of threshold voltage and current collapse phenomenon is described in this letter.
All Science Journal Classification (ASJC) codes
- Electronic, Optical and Magnetic Materials
- Electrical and Electronic Engineering