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arXiv · 2211.10787

A new semiconducting perovskite alloy system made possible by gas-source molecular beam epitaxy

Ida Sadeghi·Jack Van Sambeek·Tigran Simonian·Michael Xu·Kevin Ye·Valeria Nicolosi·James M. LeBeau·R. Jaramillo
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Abstract

Optoelectronic technologies are based on families of semiconductor alloys. It is rare that a new semiconductor alloy family is developed to the point where epitaxial growth is possible; since the 1950s, this has happened approximately once per decade. Here we demonstrate epitaxial thin film growth of semiconducting chalcogenide perovskite alloys in the Ba-Zr-S-Se system by gas-source molecular beam epitaxy (MBE). We stabilize the full range y = 0 ... 3 of compositions BaZrS$_{(3-y)}$Se$_y$ in the perovskite structure, up to and including BaZrSe$_3$, by growing on BaZrS$_3$ epitaxial templates. The resulting films are environmentally stable and the direct band gap ($E_g$) varies strongly with Se content, as predicted by theory, covering the range $E_g$ = 1.9 ... 1.4 eV for $y$ = 0 ... 3. This creates possibilities for visible and near-infrared (VIS-NIR) optoelectronics, solid state lighting, and solar cells using chalcogenide perovskites.

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Ida Sadeghi, Jack Van Sambeek, Tigran Simonian, Michael Xu, Kevin Ye, Valeria Nicolosi, James M. LeBeau, R. Jaramillo. 2022-11-19. A new semiconducting perovskite alloy system made possible by gas-source molecular beam epitaxy. https://arxiv.org/abs/2211.10787

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