High-performance self-powered ultraviolet Ti₃C₂T_x/GaN Schottky photodiode with an interdigitated electrode

Ultraviolet photodetectors (UV-PDs) with high sensitivity and fast optical response have become an important part of modern optoelectronic information transmission and communication systems. In this paper, a high-performance self-powered titanium carbide (<i>T</i><i>i</i>₃<i>C</i>₂<i>T</i>_x)/gallium nitride (GaN) Schottky UV-PD with an interdigitated electrode was developed. A Schottky-contacted <i>T</i><i>i</i>₃<i>C</i>₂<i>T</i>_x interdigitated electrode was successfully fabricated on GaN substrates using a spray coating method. The as-prepared <i>T</i><i>i</i>₃<i>C</i>₂<i>T</i>_x/<i>G</i><i>a</i><i>N</i> UV-PD exhibits excellent optoelectronic properties. Under zero bias and weak UV illumination (48µ<i>W</i>/<i>c</i><i>m</i>²), the device demonstrates an ultra-low dark current (2.818×10^-10<i>A</i>) and a fast response speed (<i>t</i>_<i>r</i>=170µ<i>s</i>/<i>t</i>_<i>f</i>=210µ<i>s</i>); the responsivity and detectivity could reach 120.78 mA/W and 1.272×10¹² Jones, respectively. Furthermore, to demonstrate the feasibility of practical application, the device was applied in a UV point-of-view imaging system and high-quality images were successfully obtained under low-light conditions. This work presents an effective approach in developing high-performance UV-PDs for optical imaging applications.