Influence of TCO intermediate thin-layers on the electrical and thermal properties of metal/TCO/p-Si Schottky structure fabricated via RF magnetron sputtering

In this paper, versatile Metal/TCO/p-Si Schottky Barrier Diodes (SBDs) with dissimilar TCO intermediate layers (ZnO and ITO) were fabricated by RF magnetron sputtering technique. An overall electrical performance comparison between the Al/ZnO/p-Si, Au/ITO/p-Si and the conventional Au/p-Si structures is carried out. The measured I-V characteristics indicate that the proposed Al/ZnO/p-Si design exhibits an outstanding capability for achieving a high rectifying ratio of 142 dB. This is mainly due to the enhanced Schottky barrier height (SBH) of 0.75 V and close to unite ideality factor (n = 1.23). Such behavior can be attributed to the enhanced interface quality achieved by introducing TCO inter-layers, which could decrease the Series resistance. A comparative study of the elaborated structures performance is carried out in which new Figures of Merit (FoM) parameters that combine both electrical and thermal stability performances are proposed. The Experimental results show that the proposed designs with ITO and ZnO sub-layers exhibits improved FoM parameters as compared to the conventional Au/p-Si structure. Moreover, this comparative study enables to the designer to acquire a comprehensive review about the Si-based SBDs design tradeoffs. It is demonstrated that the insertion of a TCO interlayer might be beneficial for avoiding the degradation related-heating effects. Therefore, the proposed designs offer the possibility of bridging the gap between superior electrical performance and high thermal stability, which makes them suitable for developing high-performance Schottky solar cells and sensing applications.