Polarization-engineered removal of buffer leakage for GaN transistors

Abstract

A dopant-free epitaxial technique is developed to achieve highly insulating buffers on semi-insulating GaN templates for nitride high electron mobility transistors by using the large polarization fields. The buffer leakage current density is reduced by several orders of magnitude, exhibiting outstanding insulating and breakdown properties. The simple polarization- and heterostructure-based solution should prove highly attractive for GaN high electron mobility transistors for analog (rf), digital, and high-voltage switching applications.