Effect of CuOx thin film thickness on the electiracal properties of CuOx/n-Si hetero junction structure

In this study, heterojunction structures were carried out by deposition of CuOx thin films on n-Si substrates according to different coating times by sol gel spin coating method. The effect of thin film thickness on electrical and optoelectrical properties of heterojunction structures was investigated. The crucial electrical parameters such as series resistance (Rs), rectification ratio (RR), ideality factor (n) and barrier height (ΦB) of heterojunction structures were calculated by analyzing I-V data. All structures were shown to be light sensitive and exhibit a rectification behavior. While the ideality values of the diodes varied between 3.05 and 5.08, the barrier heights varied between 0.64-0.71 eV and the series resistance values between 3-42 Ω. The electrical behavior of the fabricated devices was investigated by measuring the capacitance-voltage (C-V), conductivity-voltage (G-V) and Series resistance (Rs-V) at different frequencies. It was determined that the capacitance, conductivity and series resistance decreased, increased and increased, respectively, with increasing frequency. This behavior is due to the presence of interface states of the fabricated devices. The electrical characterization results showed that all fabricated devices can be operated as optical sensors or photodiodes in optoelectronic fields.