Hydrogenation of silicon-nanocrystals-embedded silicon oxide passivating contacts

Masashi Matsumi; Kazuhiro Gotoh; Markus Wilde; Yasuyoshi Kurokawa; Katsuyuki Fukutani; Noritaka Usami

doi:10.1088/1361-6528/ad115d

Hydrogenation of silicon-nanocrystals-embedded silicon oxide passivating contacts

Nanotechnology. 2023 Dec 21;35(10). doi: 10.1088/1361-6528/ad115d.

Authors

Masashi Matsumi¹, Kazuhiro Gotoh^{1

2

3}, Markus Wilde⁴, Yasuyoshi Kurokawa¹, Katsuyuki Fukutani⁴, Noritaka Usami¹

Affiliations

¹ Graduate School of Engineering, Nagoya University, Nagoya, Japan.
² Graduate School of Science and Technology, Niigata University, Niigata, Japan.
³ Interdisciplinary Research Center for Carbon-Neutral Technologies, Niigata University, Niigata, Japan.
⁴ Institute of Industrial Science, The University of Tokyo, Tokyo, Japan.

PMID: 38035398
DOI: 10.1088/1361-6528/ad115d

Abstract

We investigate the effect of hydrogen passivation of dangling bonds in silicon oxide passivating contacts with embedded silicon nanocrystals (NAnocrystalline Transport path in Ultra-thin dielectrics for REinforced passivation contact, NATURE contact). We first investigated the differences in electrical properties of the samples after hydrogen gas annealing and hydrogen plasma treatment (HPT). The results show that the NATURE contact was efficiently passivated by hydrogen after HPT owing to the introduction of hydrogen radicals into the structure. Furthermore, we examined the dependence of process parameters such as HPT temperature, duration, and H₂pressure, on the electrical properties and hydrogen depth profiles. As a result, HPT at 500 °C, 15 min, and 0.5 Torr resulted in a large amount of hydrogen inside the NATURE contact and the highest implied open-circuit voltage of 724 mV. Contact resistivity and surface roughness hardly increased when HPT was performed under the optimized condition, which only improved the passivation performance without deteriorating the electron transport properties of the NATURE contact.

Keywords: composite material; hydrogenation; passivating contact; silicon nanocrystals; silicon oxide.