In deposited on UHV cleaved p-WSe2 (0001) is investigated by photoelectron spectroscopy (XPS, UPS), low energy electron diffraction (LEED), scanning electron microscopy (SEM), and surface photovoltage (SPV) experiments. In forms an atomically abrupt, non-reactive metallic overlayer on the substrate. It grows in threedimensional clusters (Volmer-Weber growth mode). The experimentally observed band bending induced by In at RT is smaller than expected by the Schottky limit. Photoemission source induced SPV values at 100 K are saturated and different for the substrate and In overlayer emission lines. The results are explained by laterally inhomogeneous electric potential distributions due to the In clustering on the semiconductor surface.