Theoretical study of the temperature dependence of electrical characteristics of Schottky diodes with an inverse near-surface layer

Abstract

Counter-doping of a near-surface layer is a well-known method of Schottky barrier height engineering. However, the temperature dependence of the electrical characteristics of such structures has not been studied until now. In this work, we present the results of our theoretical study of the temperature dependence of the Schottky diode parameters. The drift-diffusion approximation was used for the calculation of I– V and C– V characteristics and the thermionic emission theory for the extraction of diode parameters. This procedure gave results in agreement with the results observed on the experimental structures. The barrier height decreases with decreasing temperature. All simulated I– V curves for the different temperatures have an almost common cross-point at certain voltage which depends on the doping concentrations and thickness of the counter-doped layer. The fact that this effect is not currently observed in experiments is probably caused by the fact that the series resistance of real structures consists of more components not only from ohmic resistance of the semiconductor bulk. For the voltage of the cross-point, the diode current is temperature independent.