Examination on the current conduction mechanisms of Au/n-Si diodes with ZnO-PVP and ZnO/Ag2WO4 -PVP interfacial layers

This study reports a comparative characterization of Au/n-Si Schottky diodes/contacts (SDs) with hydrothermally synthesized ZnO-PVP and ZnO/Ag2WO4-PVP interfacial layers, which outperforms conventional metal-semiconductor Schottky diode structures. This characterization is important because these structures outperform traditional metal-semiconductor Schottky diodes due to the presence of an interfacial layer, allowing barrier height control, surface passivation, and leakage current reduction. Based on the thermionic emission (TE) theory assumed to be the dominant current mechanism across, SDs parameters were obtained. As expected, nonlinear rectifying behavior was observed for all SDs, and the divergence from linearity is caused by factors such as the interfacial layer thickness, the interface-state (N-ss) density, and the bulk series resistance (R-s). It is important to note that the rectification ratio (RR) of the Au/(ZnO/Ag2WO4-PVP)/n-Si (MPS2) SD is 48 times more than the RR of the Au/n-Si SD and 11 times greater than the RR of the Au/ ZnO-PVP/n-Si (MPS1) SD. The ideality factor (n) and zero-bias barrier height (f(B0)) were found to be 7.73 and 0.563 for MS, 6.23 and 0.604 for MPS, 4.83 and 0.684 for MPS2 SD. Nearly an order of magnitude less N-ss exists for the MPS2 diode than the MS diode. According to these findings, the ZnO-PVP and ZnO/Ag2WO4-PVP interfacial layers stop Au and n-Si from reacting or diffusing with one another while also passivating the active dangling bonds at the Si surface. The methods of Cheung and Norde were also used to extract the R-s, n, and f(B). The inconsistency between the parameters obtained from these methods could be attributed to the regions where the methods are used differ. [GRAPHICS] .