The Effects of Surface Oxidation and H-Termination Processes Applied to Si Using Electrolytic Hydrogen Peroxide Solution to The Produced Cu/p-Si Schottky Contact Parameters

Abstract

By using electrolytic hydrogen peroxide (H2O2) solution, oxidation and H-termination processes were applied to the p-Si crystal surface, which will be used for Cu/p-Si Schottky contact production, in a selective and controlled manner. Before the oxidation and H-termination processes, the p-Si(100) wafer used in this study was subjected to conventional chemical cleaning, and ohmic contact was made using pure aluminum (99.99%) metal on its back surface. The p-Si/Al with ohmic back contact was divided into three parts. A rectifying contact was immediately made to the front surface of one of them by using pure copper (99.98%) metal and called the REF (Reference) sample. The front surface of one of the remaining two p-Si/Al parts was oxidized, and the front surface of the other was H-Terminated. Rectifier contacts were made for both using pure copper (99.98%) metal and were named MIS (metal-insulator-semiconductor) and SP (surface passivated), respectively. Current-voltage (I-V) measurements of Schottky diodes of REF, MIS, and SP samples were performed at room temperature and in the dark. From the obtained data, the ideality factor (n), barrier height (Fbo), and series resistance (Rs) values of the samples were determined. As a result of the investigations, it was observed that the surface oxidation and H-Termination processes caused a decrease in the rectification factor and Fbo values of MIS and SP samples. These interesting situations were interpreted by the double-layer theory, which Bardeen predicted could exist on the surface of a semiconductor crystal and contribute to its work function.