Analysis of current voltage measurements on Au/Ni/n-GaN Schottky contacts in a wide temperature range

摘要

Current-voltage characteristics of Au/Ni/n-GaN Schottky contacts have been measured in the60-320 K temperature range. The zero bias barrier height, bo  and ideality factor, n have beenstudied as a function of temperature. The sharp increase in ideality factor at low temperatureshas been explained as an effect of thermionic field emission. The deviation of thecharacteristics from the ideal thermionic behaviour are more pronounced with a decrease intemperature, in which the results obtained indicate the presence of other current transportmechanisms in the 60-280 K temperature range and the dominance of pure thermionicemission current at 300 K. The increase in barrier height with increasing temperature hasbeen explained as an effect of barrier inhomogeneities.