Polarization-induced Zener Tunnel Diodes in GaN/InGaN/GaN Heterojunctions

TL;DR

This paper investigates polarization-induced Zener tunnel diodes in GaN/InGaN/GaN heterojunctions, demonstrating how InGaN layer composition affects tunneling currents and discussing challenges for future nitride-based tunneling transistors.

Contribution

It introduces polarization-induced Zener tunnel junctions in GaN/InGaN/GaN heterostructures and analyzes how InGaN composition influences tunneling, providing insights for nitride-based tunneling FET development.

Findings

Weak temperature dependence of reverse-bias tunneling current

Increased tunneling current with higher In composition

Identification of challenges for nitride-based tunneling transistors

Abstract

By the insertion of thin InGaN layers into Nitrogen-polar GaN p-n junctions, polarization-induced Zener tunnel junctions are studied. The reverse-bias interband Zener tunneling current is found to be weakly temperature dependent, as opposed to the strongly temperature-dependent forward bias current. This indicates tunneling as the primary reverse-bias current transport mechanism. The Indium composition in the InGaN layer is systematically varied to demonstrate the increase in the interband tunneling current. Comparing the experimentally measured tunneling currents to a model helps identify the specific challenges in potentially taking such junctions towards nitride-based polarization-induced tunneling field-effect transistors.