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arXiv · 2605.14329

Depletion-mode N-polar AlN-based high electron mobility transistors with improved on/off ratios

Xu Yang·Sheng Zhang·Ke Wei·Xinhua Wang·Xinyu Liu·Itsuki Furuhashi·Markus Pristovsek
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Abstract

We report N-polar AlN-based high-electron mobility transistors (HEMTs) with a GaN channel thickness of 5.2 nm on N-polar AlN on sapphire. The threshold voltage is around -2.4 to -3.0 V with saturation currents over 240 mA/mm and on/off ratios as high as 10,000, much higher than previously reported N-polar AlN-based HEMTs. The high on/off ratio is attributed to the use of an abrupt AlN/GaN heterostructure with a dedicated AlN transition layer, together with improved gate leakage. The high frequency properties as well as the on-resistance of ~20 Ohm mm are all limited by the 2000 Ohm/square sheet resistance of the channel layer.

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Xu Yang, Sheng Zhang, Ke Wei, Xinhua Wang, Xinyu Liu, Itsuki Furuhashi, Markus Pristovsek. 2026-05-14. Depletion-mode N-polar AlN-based high electron mobility transistors with improved on/off ratios. https://arxiv.org/abs/2605.14329

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