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arXiv · 2202.01777

Tuning carrier density and phase transitions in oxide semiconductors using focused ion beams

Hongyan Mei·Alexander Koch·Chenghao Wan·Jura Rensberg·Zhen Zhang·Jad Salman·Martin Hafermann·Maximilian Schaal·Yuzhe Xiao·Raymond Wambold·Shriram Ramanathan·Carsten Ronning·Mikhail A. Kats
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Abstract

We demonstrate spatial modification of the optical properties of thin-film metal oxides, zinc oxide and vanadium dioxide as representatives, using a commercial focused ion beam (FIB) system. Using a Ga+ FIB and thermal annealing, we demonstrated variable doping of a band semiconductor, zinc oxide (ZnO), achieving carrier concentrations from 10^18 cm-3 to 10^20 cm-3. Using the same FIB without subsequent thermal annealing, we defect-engineered a correlated semiconductor, vanadium dioxide (VO2), locally modifying its insulator-to-metal transition (IMT) temperature by range of ~25 degrees C. Such area-selective modification of metal oxides by direct writing using a FIB provides a simple, mask-less route to the fabrication of optical structures, especially when multiple or continuous levels of doping or defect density are required.

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Hongyan Mei, Alexander Koch, Chenghao Wan, Jura Rensberg, Zhen Zhang, Jad Salman, Martin Hafermann, Maximilian Schaal, Yuzhe Xiao, Raymond Wambold, Shriram Ramanathan, Carsten Ronning, Mikhail A. Kats. 2022-02-03. Tuning carrier density and phase transitions in oxide semiconductors using focused ion beams. https://arxiv.org/abs/2202.01777

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