Scaling issues for AlGaN/GaN HEMTs: performance optimization via devices geometry modelling

TL;DR

This paper uses Monte Carlo simulations to demonstrate that reducing the source-to-gate distance in AlGaN/GaN HEMTs can enhance device performance by increasing the potential barrier, addressing scaling challenges.

Contribution

It introduces a device geometry modeling approach to optimize AlGaN/GaN HEMT performance through source-to-gate distance scaling.

Findings

Reducing source-to-gate distance improves device performance.

Downscaling increases the potential barrier between source and gate.

Geometry optimization can mitigate scaling issues in GaN HEMTs.

Abstract

The potential barrier between source and gate in HEMTs and between source and channel in MOSFET controls the current output and the velocity injection of electrons in the channel [1], [2]. In non self aligned structures the electric field behavior along the channel, for fixed applied voltages, is determined by the contacts positions. Anyway, in GaAs based HEMTs, the geometry of the device appears to be not determinant for the output current due to saturation effects. On the other hand, the GaN based technology still offers the possibility to enhance devices output current handling contacts distances. In this paper we will present Monte Carlo simulations results which show how a downscaling of the Source to Gate distance could improve the device performances inducing an higher potential barrier between source and gate.