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arXiv · 1906.04947

Wurtzite Phonons and the Mobility of a GaN/AlN 2D Hole Gas

Abstract

To make complementary GaN electronics more than a pipe dream, it is essential to understand the low mobility of 2D hole gases in III-Nitride heterostructures. This work derives both the acoustic and optical phonon spectra present in one of the most prominent p-channel heterostructures (the all-binary GaN/AlN stack) and computes the interactions of these spectra with the 2D hole gas, capturing the temperature dependence of its intrinsic mobility. Finally, the effects of strain on the electronic structure of the confined 2D hole gas are examined and a means is proposed to engineer the strain to improve the 2D hole mobility for enhanced p-channel device performance, with the goal of enabling wide-bandgap CMOS.

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Samuel James Bader, Reet Chaudhuri, Martin Schubert, Han Wui Then, Huili Grace Xing, Debdeep Jena. 2019-06-12. Wurtzite Phonons and the Mobility of a GaN/AlN 2D Hole Gas. https://doi.org/10.1063/1.5099957

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