Reverse-bias leakage in Schottky diodes

Abstract

Reverse-bias current-voltage (I-R-V) characteristics of Al-n /GaAs Schottky diodes have been studied in a temperature range from 92 to 333 K. The results are explained on the basis of phonon-assisted tunnelling model. It is shown that the temperature dependence of the reverse current I-R could be caused by the temperature dependence of the electron tunnelling rate from traps in the metal-semiconductor interface to the conduction hand of the semiconductor. Temperature-dependent I-R-V data obtained by Zhang et al J. Appl. Phys. 2006; 99: 023703 and Osvald et al Microelectron. Eng. 2005; 81: 181 for Schottky diodes fabricated on n-GaN are reinterpreted in terms of a phonon-assisted tunnelling model. The temperature and bias voltages dependences of an apparent barrier height (activation energy) observed by other researchers are also explained in the framework of this model.