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arXiv · 2606.17401

Coexistence of Donor and Acceptor Hydrogen States in n-Type InN

Masaki Kobayashi·Yudai Yamashita·Kazuyuki Hirama·Yoshitaka Taniyasu
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Abstract

Hydrogen often exhibits amphoteric behavior in semiconductors, but its role is in n-type InN remains unresolved. Wurtzite InN is a narrow-gap semiconductor with high electron mobility and is therefore attractive for high-speed electronics and optoelectronic applications. Here we use hard x-ray photoemission spectroscopy (HAXPES) to probe hydrogen-related electronic structure in as-grown and post-annealed InN thin films prepared at different grown temperatures. Post annealing, which reduces the concentration of hydrogen impurities in the films, shifts the core-level spectra toward lower binding energy, consistent with a chemical-potential shift associated with the passivation of electron carriers. In the valence-band spectra, an acceptor-like in-gap feature near the valence-band maximum is suppressed after annealing. Together with the established donor-like behavior of hydrogen in InN, these results suggest that acceptor H- states coexist with donor H+ states in InN. The coexistence of these opposite hydrogen charge states provides a microscopic picture of hydrogen-driven compensation in InN and highlights the amphoteric nature of hydrogen even in a highly n-type semiconductor.

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Masaki Kobayashi, Yudai Yamashita, Kazuyuki Hirama, Yoshitaka Taniyasu. 2026-06-16. Coexistence of Donor and Acceptor Hydrogen States in n-Type InN. https://arxiv.org/abs/2606.17401

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