Analysis of temperature dependent I-V measurements on Pd/ZnO Schottky barrier diodes and the determination of the Richardson constant

Temperature dependent current-voltage (I-V) and Hall measurements were performed on Pd/ZnO Schottky barrier diodes in the range 20-300 K. The apparent Richardson constant was found to be 8.60 x 10(-9) A K-2 cm(-2) in the 60-160 K temperature range, and mean barrier height of 0.50 eV in the 180-300 K temperature range. After barrier height inhomogeneities correction, the Richardson constant and the mean barrier height were obtained as 167 AK(-2) cm(-2) and 0.61 eV in the temperature range 80-180 K. respectively. A defect level with energy at 0.12 eV below the conduction band was observed using the saturation current plot and (0-11 +/- 0.01) eV using deep level transient spectroscopy measurements. (C) 2008 Elsevier B.V. All rights reserved.