Schottky barrier inhomogeneity at metal/semiconductor interfaces has been considered an important factor in explaining the non-ideal behaviour of the Schottky diodes. However, qualitative understanding of the factors controlling the Schottky barrier later al variations requires a technique capable of probing both the local chemical and structural speci fics of the metal/semiconductor interface and the corresponding band bending at the surface. This requirement has partly been met by adding submicrometer la teral resolution (≤ 0.1 µm) to the photoelectron spectroscopy, a chemically sensitive method with a probing depth that can be set to be less than 100 Å and the Schottky barriers can be determined from the energy shifts of the photoelectron spectra. The ac cess of photoelectron spectromicroscopy to microscopic interface properties will be illustrated by some recent results for metal/GaN interfaces, obtained using the scanning photoelectron microscope at the ELETTRA light source. The investigations were f ocu sed on development of chemical heterogeneity at related to the defective structure of the GaN epilayers. Using case studies of technologically important Au, Ni, Ti/GaN contacts lateral variations in the microscopic morphology and their effect on the l ocal Schottky barriers will be presented and discussed. The measured negligible lateral band bending fluctuations despite the differences in the film thickness and chemical composition has been identified as a property of the metal/GaN interfaces, not w el l un derstood in the frame of the existing theoretical models. ˙. s∆∆ˇ.