Enhanced Photoelectrical Performance of Al/p-Si/ZnO:B4C/Al Photodiodes Fabricated via the Sol-Gel Spin-Coating Technique

Al/p-Si/ZnO:B4C/Al Photodiodes Fabricated via the Sol-Gel Spin-Coating Technique

Abstract

In this study, Al/p-Si/ZnO:B₄C/Al structured photodiodes were fabricated using the sol-gel spin-coating method, and the effect of B₄C doping (0, 1, 3, 5, and 10 wt.%) on device performance was investigated. The thin films were characterized by FE-SEM and EDX analyses, confirming the formation of crack-free, homogeneous, and nanostructured surfaces on p-Si substrates. Electrical and photoresponse measurements were carried out under illumination intensities ranging from 20 to 100 mW cm^-2. At 100 mW cm^-2, the photocurrent values were determined as 56×10^-4, 16.4×10^-5, 6.97×10^-5, 3.43×10^-5, and 2.67×10^-5 A for 0%, 1%, 3%, 5%, and 10% B₄C contents, respectively. It was observed that the photocurrent decreased with increasing B₄C concentration, although the photoresponse could be tuned by adjusting the doping level. The results demonstrate that ZnO:B₄C photodiodes were successfully fabricated and that their optoelectronic performance can be effectively controlled through the B₄C doping ratio.