Properties of Pt/Au Schottky contacts on GaN prepared by pulsed laser deposition

The fabrication process and electrical properties of Pt/Au Schottky structures on GaN are presented. The GaN unintentionally doped epitaxial layers were grown on a sapphire substrate by metal-organic chemical vapor deposition (MOCVD). Schottky structures were fabricated by pulsed laser deposition of a Pt/Au multilayer. The influence of the surface treatment by wet chemical etching prior to the Schottky barrier metal deposition on the GaN surface properties was investigated by scanning electron microscopy (SEM). The electrical properties of the Schottky structures have been extracted from I-V and C-V measurements. A correlation between the surface properties and the electrical parameters of the Schottky contact is analysed.