Illumination effect on electrical characteristics of pristine PVA based broadband photodetector

In this paper, we present the opto-electrical characteristics of the fabricated PVA based photodetector on a low thermal mass platform having the capability to respond from UV to mid-IR region. The taxonomic study of current-voltage characteristics of the fabricated device has been carried out and the Metal-Semiconductor Polymer-Metal structure indicated the characteristics of Schottky diode. The barrier height (φ_B0) of the metal/polymer interface, the bulk resistance (R_s), ideality factor (n), and the reverse saturation current (I₀) of the fabricated device were determined. The effect of illumination was investigated on the electrical parameters in the forward and reverse bias current-voltage characteristics. It was found that the barrier height (φ_B0) as well as series resistance (R_s) decreased while ideality factor (n) increased under illumination. The insight of our study reveals that the thickness and the semi-crystalline morphology of the photoactive layer as well as the fabrication process need to be simultaneously optimized for enhancing the figure of merit of this class of the photodetector.