Interfacial reactions and Schottky barrier properties of composite patterned metal/GaN interfaces

Scanning photoelectron spectromicroscopy has been applied to study the interfacial chemistry and electronic properties of adjacent patterned Au and Ti/Au regions on GaN, fabricated by metal deposition at room temperature through appropriate masks. The lateral variations in the composition of the interfacial phases before and after annealing to 800 °C and their effect on local band bending are determined. The very small difference in the Schottky barrier heights measured in the adjacent Au/GaN and Ti/Au/GaN regions is identified as a property of the metal/GaN interfaces not predicted by the existing theoretical models.