Enhancement of performance of Ga incorporated ZnO UV photodetectors prepared by simplified two step chemical solution process

The present study establishes the UV photodetector capability of Zinc Oxide (ZnO) and Gallium in-corporated ZnO (GZO) thin films prepared by a simplified two-step chemical bath deposition technique. The prepared UV detectors were characterized by tools such as XRD, SEM, UV, PL and Photoresponse to in-vestigate their properties. The structural study revealed the enhancement of film crystallinity with respect to Ga doping level. The optical studies confirm the higher absorption at UV range for 3% Ga doped ZnO film. From PL study, the green emission observed at 522 nm is associated with the defects from oxygen vacancies (V-o(+)). Once the UV light is irradiated on the GZO film surface, electrons and holes are generated as the illumination energy is larger than the ZnO bandgap energy, known as above-band energy illumination. The photo-generated holes then neutralize the chemisorbed ions causing the release of electrons in the con-duction band of ZnO, this could increase the photocurrent. In this study, the calculated photo-detectivity (D*), responsivity (R) and external quantum efficiency (EQE) of the prepared UV detectors are 1.24 x10(10) jones, 0.38 AW(-1), and 125.10% respectively for 3% Ga doped ZnO film. These parameters are noticeable and this study proves that GZO films in fact work as good sensitive UV detectors. (c) 2021 Elsevier B.V. All rights reserved.

Automated summary

This study establishes the UV photodetector capability of Zinc Oxide (ZnO) and Gallium-incorporated ZnO (GZO) thin films prepared by a simplified two-step chemical bath deposition technique. The study characterizes the prepared UV detectors and investigates their properties using various analytical tools. The results show that Ga doping improves the crystallinity of the films and enhances their absorption of UV light. The study also calculates the photo-detectivity, responsivity, and external quantum efficiency of the UV detectors, demonstrating the potential of GZO films as sensitive UV detectors.