Sevgili, OmerOrak, IkramOzel, Sultan SuleymanOzel, Faruk2026-02-282026-02-2820250031-89491402-4896https://doi.org/10.1088/1402-4896/add65bhttps://hdl.handle.net/20.500.12403/6046This study presents a structural analysis of NiO and the fabrication of Al/NiO/p-Si isotype heterojunction photodiode (PD) as well as an investigation of the photo-response and photovoltaic (PV) properties of the PD in the various illumination intensities. The series resistance (RS) value of the Al/NiO/p-Si was calculated to be 0.11 k Omega using Ohm's Law at 2 V. This result corroborates the assertion that RS is the pivotal parameter for attaining optimal performance in a PD. The NiO has made a notable improvement to the electrical parameters such as ideality factor, barrier height, and series resistance. The spectral responsivity R value of the PD was calculated as 1.59 A W-1 at -2 V. The Al/NiO/p-Si exhibited a short-circuit current density (JSC) of 60.38 mAcm-2, an open-circuit voltage (VOC) of 149.0 mV, a fill factor (FF) of 27.67%, and a power conversion efficiency (PCE) of 2.49%. In view of the experimental results, it can be concluded that NiO represents a promising material for the optimization of heterojunction photodiode applications.eninfo:eu-repo/semantics/closedAccessNiOphotodiodephotoresponseoptoelectronicArticle100610.1088/1402-4896/add65b2-s2.0-105006748727Q2WOS:001493147700001Q2