Ultrasound-Assisted Method for Preparation of Ag2S Nanostructures: Fabrication of Au/Ag2S-PVA/n-Si Schottky Barrier Diode and Exploring Their Electrical Properties

Au/n-Si metal/semiconductor (MS) Schottky barrier diodes with and without (Ag2S-PVA) interlayer were prepared by the ultrasound-assisted method and their electric and dielectric properties were examined by using current-voltage (I-V) and capacitance-voltage (C-V) measuring devices. The structural, optical and morphological characteristics of the (Ag2S-PVA) were studied by x-ray diffraction (XRD), scanning electron microscopy (SEM) and UV-Visible spectroscopy. The observed peaks in the XRD pattern are related to the alpha-phase of silver sulfide. The UV-Visible spectrum of (Ag2S-PVA) shows the quantum confinement and SEM image proves the grain size in nano-scale. The ideality factor (n) and barrier height (BH) at zero bias (phi(B0)(I-V)) were acquired from the I-V data. On the other hand; Fermi energy (E-F), donor concentration atoms (N-D), and BH (phi(B)(C-V)) values were obtained from the reverse bias C-V data. The voltage-dependent resistance profile (Ln(R-i)-V) was obtained by applying Ohm's law and also by the Nicollian-Brews methods. Also, considering the voltage-dependent n and BH, N-ss-(E-c-E-ss) profile was acquired from the forward biases I-V characteristics. Depending on high, intermediate and low biases ln(I)-Ln(V) curves have three linear regions with distinct slopes for MS and MPS structures. The predominant current-transport mechanisms were obtained in related regions via trap-charge limited current and space-charge limited current, respectively. These outcomes indicate that the (Ag2S-PVA) interlayer enhanced the performance of the diode considerably in terms of high rectifier rate (RR), shunt resistance (R-sh), and low surface states (N-ss) and series resistance (R-s). Thus, the (Ag2S-PVA) interlayer can be used in MS type diode instead of a traditional insulator layer.