Analysis of Double Gaussian Distribution at the Interface of Ni/Ta2O5/P-Si Schottky Barrier Diodes Using Temperature Dependent Current-Voltage (I-V) Measurements

The electrical properties have been investigated for Ni/Ta2O5/p-Si Metal/insulator/semiconductor SBD in the temperature regime 175–400 K. The electrical parameters were analyzed using current-voltage characteristics as a function of operating temperature. It is observed that the Schottky barrier height increased whereas ideality factor and series resistance decreased with increasing the operating temperature. The characteristic temperature (To) value calculated from Norde and Cheung methods was compared. This analysis showed that To value extracted from both the techniques are in close agreement with each other. Experimental results revealed that the thermal coefficient was −4.5 mV/K. The Gaussian distribution of the barrier height was estimated from the plot of zero-bias barrier height (Φbo) versus 1/2kT plot and the estimated value of (Φbo) of 0.92 eV and 0.79 eV with standard deviation (σ0) of 0.023 V and 0.014 V, respectively. The mean BH and the Richardson constant values were determined using ln (Io/T2)-q2σ02\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$ {\sigma}_0^2 $$\end{document}/2(kT)2 versus 1000/T plot and were 0.89 eV and 0.76 eV and 30.03 and 26.85 A/cm−2 K−2, respectively. In addition to the thermionic emission process, two more conduction mechanisms such as Poole-Frenkel emission in the temperature regime 175–275 K and Schottky emission dominant beyond 300 K temperature were noticed.