Comparative study of electrical parameters of Au/GaN and Hg/GaN Schottky diodes

p. 471-474

In this work, we have carried out a comparative study of electrical parameters determined from the current-voltage (I-V) and capacitance-voltage (C-V) characteristics of Au/n-GaN and Hg/n-GaN structures. The analysis of the (I-V) curve for the Au/n-GaN structure showed an ideality factor, barrier height and series resistance of about 1.02, 0.65 eV and 84 Ω, respectively. While for the Hg/n-GaN structure, the values determined are respectively 1.13, 0.65 eV and 670 Ω. The barrier heights and doping concentrations determined from the (C-V) curves are of the order of 1.17 eV and 8.16×1016 cm-3 for the Au/n-GaN Schottky diode and 1.34 eV and 1.87×1016 cm-3 for the Hg/n-GaN Schottky diode. The interfacial state density Nss calculated is equal to 1.09×1012 cm-2 eV-1 for the two diodes.