Illumination and voltage effects on the forward and reverse bias current-voltage (I-V) characteristics in In/In2S3/p-Si photodiodes

Abstract

The illumination and voltage effects on the I-V measurements of the fabricated In/In2S3/p-Si photodiode were investigated in dark and under various illumination intensities (20–100 mW/cm2) between ± 2 V. Two linear regions in the forward-bias ln(I)-V plots were observed. The value of diode ideality factor (n) had an increasing trend with increasing illumination intensity while the barrier height (?Bo) had a decreasing trend due to the increase of photocurrent. The photodiode properties were also investigated, and the value of linear-dynamic value range (LDR) was found to be 20.56 dB. The photoresponse (Iph/Idark), the photoresponsivity (R), and specific detectivity (D*) of the photodiode were calculated as a function of the illumination. The open-circuit voltage (Voc) and short-current (Isc) were found to be 0.36 V and 2.87 mA under 100 mW.cm?2 illumination intensity, respectively. The possible conduction mechanisms (CMs) were investigated using the forward ln(I)-V and reverse ln(I)-V0.5 plots. The energy-dependent surface states (Nss) profile was extracted from the positive I-V data by considering voltage-dependent barrier height (BH) and ideality factor (n) in dark and illumination at 100 mW/cm2. © 2021, The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.