I-V Characteristics of Two Au/Ni/n-GaN Schottky Diodes with Different Structure

The rectifying characteristics of two Schottky diodes with different structures were investigated. These two different structures were processed by induced couple plasma (ICP) etching,of which I-V characteristic curve, reverse leakage current density, the Schottky barrier height, and the ideality factor were measured and extracted. It is found that the Schottky barrier height is determined by pinned Fermi level of the n-GaN films. As the oxide was removed due to the ICP etching processing, the surface states density was increased, thus the chance of tunneling. Therefore the contact between metal and n-GaN of the transition is more Ohmic-like after ICP etching.