Akademik Veri Yönetim Sistemi
Journal of Materials Science: Materials in Electronics, cilt.37, sa.3, 2026 (SCI-Expanded, Scopus)
This study presents a comprehensive impedance spectroscopy (IS) analysis of Au/Ti/AlN/n-Si metal–oxide semiconductor (MOS) structures, with the aim of elucidating their dielectric and interfacial properties under different bias and frequency conditions. The real (Z′) and imaginary (Z′′) components of impedance were measured across 100 Hz–1 MHz and DC biases between 1 and 4 V, and the data were modeled using an equivalent circuit composed of a series resistance (Rs), a parallel resistance (Rp), and a parallel capacitance (Cp). The impedance spectra revealed a clear capacitive-to-resistive transition, while Cole–Cole plots consistently exhibited a single semicircle, confirming the presence of a unique relaxation mechanism. Relaxation times (τ), extracted both from Z′′–f peaks and Rp∙Cp fitting, showed excellent agreement and demonstrated bias-dependent evolution, with accelerated relaxation at moderate bias and slower dynamics at higher bias due to trap saturation. Notably, Cp remained nearly constant across all biases, while Rp varied systematically, reflecting the influence of interfacial states. The analysis of normalized interface trap density further indicated progressive trap passivation with increasing bias, underscoring the stability of the AlN/Si interface. These findings validate the equivalent circuit model and highlight AlN as a promising dielectric material for high-frequency, low-leakage MOS applications, offering predictable relaxation behavior and reduced trap activity compared to conventional high-k dielectrics.