Ultraviolet and visible nitride photodetectors: applications

One of the main interests of wide-bandgap materials such as diamond, III-nitrides or SiC is their intrinsic ability to perform selective ultraviolet detection. Over the rest, III-nitrides present the undoubted advantage of tuning the absorption edge in a wide spectral range by varying the Al and In mole fractions in AlGaN and InGaN ternary alloys. This property makes them suited for many applications in the ultraviolet and visible ranges. This work presents a short view of fabrication and spectral responses of AlGaN- and InGaN-based photodetectors and their potential use in industrial, environment, military and biomedical research. For visible detection, as an alternative to InGaN bulk-based devices, InGaN/GaN multiple-quantum-well (MQW) photodiodes are also described.