Influence of illumination intensity on the electrical properties of Al/NOA65/p-Si/Al heterojunction MPS device

Abstract

In this work, we report photodiode behavior on metal polymer semiconductor device with photopolymer interfacial layer for the first time. For this purpose, Al/NOA65/p-Si device was fabricated and the electric and dielectric parameters were investigated under the light and as well as dark. A good rectification ratio (1200 at 2 V) was achieved from the current-voltage (I-V) measurements in the dark. The reverse bias saturation current varied linearly with the illumination level, indicating to the photodiode behavior. The photosensitivity of the device reached 670 at 120 mW/cm(2). According to the frequency and voltage dependency of capacitance (C), conductance (G), and the derived dielectric parameters, the interface states and the surface dipoles at the interfacial layer were effective on the device. Besides, the changes in the mentioned parameters under illumination were associated with the charge carriers created by the light and the decrease in the series resistance.