Low-Voltage p-i-n GaN-Based Alpha-Particle Detector With High Energy Resolution

The pursuit of low power consumption, high charge collection efficiency (CCE), and high energy resolution is critical for the development of high performance GaN-based alpha-particle detectors. In this letter, we fabricated a low-voltage p-i-n GaN-based alpha-particle detector with superior energy resolution. The detector exhibits a very low leakage current of pA level even at -100 V and high CCEs of 31% and 92% at zero bias and reverse bias of 50 V, respectively. Meanwhile, the detector demonstrates a high energy resolution of 2.48% at -20 V. These excellent performances are attributed to the artificially enlarged path of alpha particles in the depletion region by employing the angular incidence measurement method and the high crystal quality of the epitaxial film grown on a single-crystal GaN substrate. In addition, the damage events caused by the alpha particles are also investigated using the Monte Carlo calculation. These results are anticipated to promote the research of radiation-hardened GaN-based detectors.