Advances in thin-film and one-dimensional UV photodetectors: Materials, architectures, and thermal stability

The increasing need of the new industrial, environmental, and biomedical fields has aggravated the research of ultraviolet (UV) photodetectors. This review discusses the advances in technology of UV photodetectors, their history of transformation through the traditional thin-film semiconductor technology to state-of-the-art one-dimensional (1-D) nanostructured technology. It is well known that wide bandgap semiconductors, (Al, In) GaN, diamond and SiC exhibit significantly better responsivity, thermal performance and response time than standard silicon-based photodetectors. Later developments have offered β-Ga₂O₃, GaN and ZnO nanowire networks, which utilize quantum confinement physics and increased surface area to provide high UV detection efficiency at high temperature operations such as in flame detection. Thermal resistance is highlighted as one of the most critical parameters to measure the preparation of lab prototypes to be used in practice. The structural design is demonstrated to have a considerable effect on the thermal behavior, which in turn determines the reliability of the device in general. As an ensemble, 1D nanostructured photodetectors have better sensitivity and enhanced stability at high-temperature conditions compared to thin-film photodetectors, and β-Ga₂O₃ is a promising material in the next generation of high-detectivity and thermally resilient UV photodetectors.