Eur. Phys. J. Appl. Phys. (2014) 68: 20101
https://doi.org/10.1051/epjap/2014140200

Temperature-dependent current-voltage characteristics in thermally annealed ferromagnetic Co/n-GaN Schottky contacts

¹ Faculty of Sciences, Department of Physics Engineering, Istanbul Medeniyet University, 34720 Istanbul, Turkey
² Faculty of Sciences and Arts, Department of Physics, Bingöl University, 12000 Bingöl, Turkey

^a e-mail: kejderha@bingol.edu.tr

Received: 9 May 2014
Accepted: 22 August 2014
Published online: 15 October 2014

Abstract

Co/n-GaN SDs has been prepared by magnetron DC sputtering technique. The Co/n-GaN SDs have annealed at 600 °C after a post-deposition. The diode parameters such as the ideality factor, barrier height and Richardson constant have been determined by thermionic emission (TE) equation within the measurement temperature range 60–320 K by the steps of 20 K in the dark. It has been seen that the parameters depend on the measurement temperature indicating the presence of a lateral inhomogeneity in the Schottky barrier. Therefore, it has been modified the experimental data by the thermionic emission (TE) mechanism with Gaussian distribution of the barrier heights by using Tung’s theoretical approach that the Schottky barrier consists of laterally inhomogeneous patches of different barrier heights. Thus, the modified Richardson plot according to Tung’s barrier inhomogeneity model [8] has given a Richardson constant of 27.66 A/(cm² K²).