β-Ga₂O₃-Based Solar-Blind Schottky Diode Alpha Particle Detector

In this article, we report a $\beta $ -Ga2O3-based solar-blind Schottky diode $\alpha $ particle detector. The 20- $\mu $ m unintentionally doped $\beta $ -Ga2O3 drift region was grown on n $^{+} \beta $ -Ga2O3 substrate. XRD rocking curve revealed high crystalline quality with a narrow full-width at half-maximum (FWHM) of 45.15 arcsec for the (002) diffraction peak. The bandgap of as-grown sample, estimated by absorption spectroscopy, was approximately 4.74 eV, placing it within the solar-blind region. The $3\times 3$ mm square $\beta $ -Ga2O3-based vertical detectors were fabricated by depositing Ni/Au Schottky contacts on drift region and Ti/Au ohmic contacts on substrate, respectively. Detection of241Am $\alpha $ particle was performed under various reverse biases reaching 33% for energy resolution and 90% for charge collection efficiency (CCE) at −140 V. The measurement under 365-nm illumination indicated strong near-UV resistance for the $\beta $ -Ga2O3-based detector compared with the SiC-based detector. These results demonstrate the promise of $\beta $ -Ga2O3 detectors for solar-blind $\alpha $ particle detection in field environments.