CMOS-Compatible Ultraviolet Photodetector Based on p-Nickel-Oxide/ n-Indium-Gallium-Zinc-Oxide Heterojunction Diode

The detection of UVA rays (wavelength of 315–400 nm) is of great interest in technological applications and scientific research. Here, this work demonstrates a complementary metal-oxide–semiconductor (CMOS)-compa- tible UVA photodetector based on p-nickel-oxide/n-indium-gallium-zinc-oxide heterojunction intended for on-chip ultraviolet (UV) detection and imaging. The UVA photo- detector exhibits a dark current density of 0.7 nA/cm
²
at a reversed bias −4 V, a 68% external peak quantum efficiency (EQE) at 340 nm, and a photoresponse time less than 7 ms. The photodetector also exhibits detectivity greater than
$10^{{10}}$
Jones and a good linear photoresponsivity. In addition, the photodetector demonstrates an excellent wavelength selectivity and UV/visible rejection ratio of 16.2, making it promising for CMOS-compatible UVA detection and imaging.