Analysis of Al2O3 high-k gate dielectric effect on the electrical characteristics of a 4H-SiC low-power MOSFET

• Published in: 2019 1st International Conference on Sustainable Renewable Energy Systems and Applications (ICSRESA) pp. 1 - 4
• Main Authors: Bencherif, Hichem, Yousfi, Abderrahim, Dehimi, Lakhdar, Pezzimenti, Fortunato, Corte, Francesco G. Della
• Format: Conference Proceeding
• Language: English
• Published: IEEE 01-12-2019
• Subjects: 4H-SiC; Aluminum oxide; Dielectrics; Electric fields; high permittivity; Leakage currents; Logic gates; MOSFET; on-state resistance; Permittivity; power MOSFET; solar power optimizers
• DOI: 10.1109/ICSRESA49121.2019.9182412

The work investigates the ability of a high-k gate dielectric material (Al 2 O 3 ) in improving the electrical performance of a low voltage 4H-SiC-based MOSFET. Such a device could be used, for example, as a low-power device in DC. DC converters for photovoltaic applications. We found that an Al 2 O 3 gate oxide layer determines a higher channel mobility, a lower oxide electric field, a good threshold voltage stability, and a low on-state resistance which is on the order of 160 kΩ × µm 2 . Although our investigations show that a gate oxide dielectric with high relative permittivity considerably improves the electrical behavior of a MOSFET in 4H-SiC, the off-state leakage current have to be carefully evaluated for a device practical use.