High-performance multicolor metal-semiconductor-metal Si photodetector enhanced by nanostructured NiO thin film

Abstract

The performance of multicolor metal-semiconductor-metal (MSM) Si photodetector was improved by integrating nanostructured NiO film on Si (100) substrate using a sol-gel spin coating technique. To investigate the photoelectric performance of Si and NiO/Si heterostructure photodetectors, Au metal interdigitated electrodes were deposited on both bare Si and NiO film/Si heterostructure by a thermal evaporator. The NiO/Si photodetector exhibited excellent reproducibility and fast photoresponse under illumination with UV (365 nm), red (625 nm) and near-infrared (850 nm) lights. In addition, the NiO/Si photodetector showed higher responsivity and sensitivity towards 365, 625, and 850 nm lights as compared to bare Si photodetector. A remarkable increase in the responsivity and sensitivity of NiO/Si photodetector were measured under 365 nm illumination. The values of responsivity and sensitivity were calculated to be higher than that of bare Si photodetector by a factor of 15 and 948, respectively. Based on the photoelectric results, nanostructured NiO film/Si heterostructure is a valuable candidate to be used in UV–Vis–NIR photodetection applications.