Far-UVC Field Emission Device at 226 nm and its Sub-Nanometer thick GaN/AlN Quantum Well Anode

D. L. Boiko; P. Demolon; J. -F. Carlin; E. Eriksson; A. Hoogerwerf; K. Bach Gravesen; A. Brimnes Gardner; M. -A. Dubois; P. Tønning; E. Zanchetta Ulsig; M. Marin; J. Tingsborg; N. Volet

arXiv · 2511.03321

Far-UVC Field Emission Device at 226 nm and its Sub-Nanometer thick GaN/AlN Quantum Well Anode

D. L. Boiko·P. Demolon·J. -F. Carlin·E. Eriksson·A. Hoogerwerf·K. Bach Gravesen·A. Brimnes Gardner·M. -A. Dubois·P. Tønning·E. Zanchetta Ulsig·M. Marin·J. Tingsborg·N. Volet

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Abstract

We report on unique features of ultra-thin GaN/AlN quantum wells and demonstrate a new field emission device for human-safe disinfection with an external quantum efficiency of 18% and superior reliability, as compared to far-UVC LEDs. We investigate the behavior of a Shockley-Read-Hall recombination via Al vacancies-oxygen complexes in AlN barriers as a function of GaN well thickness and come to the conclusion that direct relaxation of confined states via mid-gap traps is prohibited and the main mechanism limiting the quantum efficiency (QE) is the carrier escape followed by non-radiative SRH recombination in the AlN barriers. As a consequence, the QE is highly dependent on the defect density, QW width and temperature which allowed us to reach a descent emissions at 226 nm wavelength although at wall plug efficiency being low, at 0.02%. We build a complete Light-Current-Voltage model and find that present device performance is limited by the self-heating and by the Child's space charge effect, both limitations can be easily addressed with some additional engineering efforts.

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D. L. Boiko, P. Demolon, J. -F. Carlin, E. Eriksson, A. Hoogerwerf, K. Bach Gravesen, A. Brimnes Gardner, M. -A. Dubois, P. Tønning, E. Zanchetta Ulsig, M. Marin, J. Tingsborg, N. Volet. 2025-11-05. Far-UVC Field Emission Device at 226 nm and its Sub-Nanometer thick GaN/AlN Quantum Well Anode. https://arxiv.org/abs/2511.03321

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