Influence of single and double interlayers on the electrical and current transport mechanism of Mo/n-Si Schottky diode and its microstructural and chemical properties

This study examined the role of Si₃N₄ and ZrO₂ on the microstructural and electrical properties of Mo/n-Si Schottky diodes (SD) as single and double insulating layers between the Mo metal and Si semiconductor. Various characterization techniques and I–V measurements were used to analyze their optical, microstructural, chemical, morphological, and electrical properties at room temperature. The direct optical bandgaps of double interlayer films are higher than the single-layer films. XRD, FESEM, EDX, XPS, and AFM analysis revealed the Si₃N₄ and ZrO₂ films formation at the interface. The electrical properties of the Mo/n-Si (MS), Mo/Si₃N₄/n-Si (MIS), Mo/ZrO₂/n-Si (MIS) Schottky diodes (SD) are associated with the properties of the Mo/Si₃N₄/ZrO₂/n-Si (MIIS) Schottky diode (SD). In comparison to the MS Schottky diode (SD), the MIS and MIIS SDs demonstrate outstanding rectifying capability and low reverse leakage current. The MIIS SD achieves the highest barrier height (BH) than the MISs and MS SDs, which has led to the BH being adjusted by the insulating layers. Furthermore, the BH, n, and series resistance were analyzed using TE, Cheung’s, Norde’s, and the Chattopadhyay methods were similar, indicating consistency and validity. The current transport mechanism was investigated based on the forward-bias I–V plot. Finally, the reverse bias I–V performance of MS SD is controlled by Schottky emission mechanism. The MIS and MIIS SD were controlled by a Poole–Frenkel mechanism at lower regions and Schottky emission mechanism at higher regions. Thus, the MIIS double interlayer SD is appropriate for high-performance electrical and optoelectronic device applications. Graphical abstract: [Figure not available: see fulltext.]