The effect of different frequencies and illuminations on the electrical behavior of MoO3/Si heterojunctions

Abstract

In this study, the rectifier properties of the transition metal oxide group n-type semiconductor molybdenum trioxide (MoO3) were investigated. The MoO3 material is a suitable material for the heterojunction structures with AFM, SEM, XRD, and 3D optical profilometer such as structural and morphological characterization result showed. Current–voltage (I-V), capacitance–voltage (C-V), and conductance-voltage (G-V) measurements of Cr/MoO3/n-Si and Cr/MoO3/p-Si heterojunction devices were made in dark and different illuminations at 300 K. The basic diode parameters were determined by using Thermionic emission (TE), and Cheung and Norde method from the I-V characteristics of the devices in dark conditions. The ideality factors of Cr/MoO3/n-Si and Cr/MoO3/p-Si devices were calculated as 1.25 and 1.22, respectively, and barrier heights of 0.69 and 0.71 eV of the devices were calculated by TE method. These results showed that the MoO3/Si heterojunction has rectifier properties. The high values of ideality can be attributed to the inhomogeneities at the interface and the series resistance. In addition, the photoconductivity properties were examined of the devices at 50 and 100 mW/cm2 illuminations. From the experimental results obtained, it was concluded that the devices can be used as photodiodes as well as showing good rectifier properties.