A Surface-Potential Based Compact Model for GaN HEMTs Directly Incorporating Polarization Charges

TL;DR

This paper introduces a new compact modeling approach for GaN HEMTs that directly incorporates polarization charges via a surface potential method, improving accuracy and material property integration.

Contribution

It presents a novel method to include polarization charges in compact models using a surface potential approach, enabling better device simulation.

Findings

Model accurately predicts I-V characteristics of GaN HEMTs.

Incorporating polarization charges improves model fidelity.

Model aligns well with experimental data.

Abstract

A method to incorporate polarization charges at heterojunctions in compact models for transistors is presented. By including the polarization sheet charge as a Dirac delta function, the Poisson equation is solved to yield a closed equation for the surface potential. A compact model for transistors based on the surface potential incorporating polarization charges describes the on-state as well as the off-state regimes of device operation. The new method of incorporating polarization charges in compact models helps make a direct connection to the material properties of the transistor. The current-voltage (I-V) curves generated by this model are in good agreement with the experimental data for GaN HEMTs.