Thin films of phthalocyaninatooxovanadium. (PcVO) were prepared on H-terminated n-doped Si(111) surfaces. The influence of different conditions of film preparation on film structure and morphology was studied. An electrical characterization of the Si/PcVO interface under illumination is presented. A photovoltaic effect was observed for light-induced electron transfer from PcVO to Si leading to a photovoltage of up to 400 mV. Spectral contributions from both Si and PcVO were detected in photocurrent spectra. The influence of electrical contact between the Au top-electrode and the Si substrate as well as interaction with ambient atmosphere on the junction properties were studied and implications for the use of such films in organic thin film heterojunctions and chemical sensors are discussed.