Findings of inhomogeneity in barrier height of Schottky junction Al/rGO-SnO2 having anomaly in theoretical and experimental value of Richardson constant: A Gaussian approach

Abstract

In this research, the temperature dependent dynamical behavior of Schottky junction Al/rGO-SnO2 has been investigated with thermionic emission (TE) theory within the temperature regime 303 K to 423 K at interval 20 K. During analysis of electrical charge transport behavior an anomalous change is observed in the value of ideality factor and barrier height with rising temperature for the junction. Experimentally derived Richardson constant (of the order 10-5A/m2K2) using TE theory is exceptionally substandard to the theoretical (of the order 106A/m2K2) values. The beauty of this work is to find out the underline physics for this discrepancy in measurement of Richardson constant (might arose due to inhomogeneity in barrier of metal-semiconductor junction) by assuming the Gaussian distribution of the barrier height with TE theory at the junction. It is obvious that the occurrence of barrier inhomogeneity across the junction leading charge transport phenomena which mostly impacting upon the parameters of Schottky diodes and its nature because of intrinsic formation of ripples and ridges. In this study, it is found that the charge transport mechanism is highly follows the single Gaussian distribution. The material characterization and its Schottky behavior in normal temperature had been published elsewhere.