Gallium Oxide Heterojunction Diodes for Improved High-Temperature Performance

Shahadat H. Sohel; Ramchandra Kotecha; Imran S Khan; Karen N. Heinselman; Sreekant Narumanchi; M Brooks Tellekamp; Andriy Zakutayev

arXiv · 2204.00112

Gallium Oxide Heterojunction Diodes for Improved High-Temperature Performance

Shahadat H. Sohel·Ramchandra Kotecha·Imran S Khan·Karen N. Heinselman·Sreekant Narumanchi·M Brooks Tellekamp·Andriy Zakutayev

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Abstract

${\beta}$-Ga${_2}$O${_3}$ based semiconductor devices are expected to have significantly improved high-power and high-temperature performance due to its ultra-wide bandgap of close to 5 eV. However, the high-temperature operation of these ultra-wide-bandgap devices is usually limited by the relatively low 1-2 eV built-in potential at the Schottky barrier with most high-work-function metals. Here, we report heterojunction p-NiO/n-${\beta}$-Ga${_2}$O${_3}$ diodes fabrication and optimization for high-temperature device applications, demonstrating a current rectification ratio of more than 10${^6}$ at 410{\deg}C. The NiO heterojunction diode can achieve higher turn-on voltage and lower reverse leakage current compared to the Ni-based Schottky diode fabricated on the same single crystal ${\beta}$-Ga${_2}$O${_3}$ substrate, despite charge transport dominated by interfacial recombination. Electrical characterization and device modeling show that these advantages are due to a higher built-in potential and additional band offset. These results suggest that heterojunction p-n diodes based on ${\beta}$-Ga${_2}$O${_3}$ can significantly improve high-temperature electronic device and sensor performance.

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BibTeX RIS

Shahadat H. Sohel, Ramchandra Kotecha, Imran S Khan, Karen N. Heinselman, Sreekant Narumanchi, M Brooks Tellekamp, Andriy Zakutayev. 2022-03-31. Gallium Oxide Heterojunction Diodes for Improved High-Temperature Performance. https://arxiv.org/abs/2204.00112

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