Optimization of structural parameters in Omega(Ω)-Shaped gate p-GaN MIS-HEMT for performance improvement

Abstract

In this paper, optimization of a novel p-GaN MIS-HEMT is performed and investigated for improved performance. In the proposed device, we have incorporated an Omega (Ω) shaped gate that surrounds the dielectric layer placed above the p-GaN layer. The Ω-shaped gate p-GaN MIS-HEMT alleviates stress on the gate dielectric. In addition, the Ω-shaped gate ensures a more uniform distribution of stress on the gate dielectric, thereby decreasing the risk of dielectric breakdown and enhancing the overall reliability of the device. The optimization has been performed with respect to gate dielectric's thickness, length and material, to achieve the optimal device performance. The validation of simulation results involved calibrating device models using experimental data. The proposed device demonstrates superior breakdown voltage, enhanced threshold voltage, and decreased gate leakage current when compared to existing state-of-the-art devices. Additionally, a set of processing steps has been proposed for the potential fabrication of the proposed device.