A strategic review on gallium oxide based Deep-Ultraviolet photodetectors: recent progress and future prospects

Abstract

With the use of UV-C radiation sterilizers on the rise in the wake of the recent pandemic, it has become imperative to have health safety systems in place to curb the ill-effects on humans. This requires detection systems with suitable spectral response to the “invisible to the naked eye” radiation leaks with utmost sensitivity and swiftness. State of the art deep-UV photodetectors based on the wide bandgap material gallium oxide have achieved responsivities up to few hundred A W−1 while the minimum response time achieved is few hundred nanoseconds. However, due to the trade-off between these two key parameters, the ultimate performance of the photodetectors remains inadequate. The focus here is to give a thorough review of the gallium oxide based photodetectors, their recent progress and future prospects. This review highlights the fundamental physics and the key parameters such as dark current, responsivity, and response time with their dependence on the material properties. Exploration of the reasons behind current scenario in the field of gallium oxide is comprehensively and critically analyzed. The key challenges which limit device performance and inhibit the realization of real-world practical detectors are also described. The lacunae currently plaguing the field is also discussed with possible remedial solutions.