Plasmon-Enhanced Hexagonal Boron Nitride Vacuum Ultraviolet Photodetector With Aluminium Nanoprism Array

Vacuum ultraviolet (VUV) detection requires high sensitivity and stability in extreme environments. We developed a plasmon-enhanced VUV photodetector composed of a 10-nm-thick hexagonal boron nitride sandwiched by aluminium nanoprism arrays (Al-NPs) and interdigital electrodes which also acting as metallic mirrors. Finite element analysis theoretically demonstrates the electric field enhancement of Al-NPs array in the VUV band. The device possessed a responsivity of 241 mA/W, an external quantum efficiency of 161%, and a specific detectivity of 5.87 × 10<sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">14</sup> Jones under 185 nm illumination, and a dark current of only 10 fA at 5 V bias and 300 K. Additionally, the integration of Al-NPs significantly suppresses dark current over a wide temperature range and the photocurrent exhibits a positive temperature coefficient from 80 K to 520 K. These findings provide new insights for plasmonic optoelectronic device design.