Synthesis and properties of Au/PVP/p-Si/Al heterojunction diode

Abstract

Properties of heterojunction diodes having polyvinyl pyrrolidone (PVP) on p-Si substrate are investigated. PVP layer has grown onto p type silicon substrate via the sol gel spin coating route @ 2000 rpm. The Front contacts have been thermally evaporated in vacuum onto the organic layer at low pressure of 10-6 T, having a diameter of 1.5 mm and a thickness around 250 ± 10 nm. In this research, the electronic parameters of Au/PVP/p-Si/Al structures have been investigated. The obtained values indicate that the electronic parameters of the diode, like ideality factor (n), saturation current, barrier height (ΦB), and rectification coefficient (R) are respectively found to be (in dark) 2.2, 0.8 μA, 0.61 V, and 1.85×104. The open circuit voltage VOC is about 0.2 V. A non-diode ideal behavior is observed and ideality factor exceeds the unity (n>5). Consequently, VOC only depends on the solar cell material. We fabricate the device in the aim to use it in solar cell, photodiode and photoconductor applications.