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 degreesC 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.