Photoelectrochemical (PEG) processes may be induced at both faces of a bipolar semiconductor electrode without application of metal contacts by using the dual electrolyte arrangement metal/electrolyte 1/semiconductor/electrolyte 2/metal and by applying a voltage to the end metal electrodes. The possibilities of semiconductor characterization (determination of action spectra and doping level) and processing (photoetching and metal electrodeposition) are discussed on the basis of model experiments, performed with n-InP wafers. The advantages of this approach over traditional PEC and electroless techniques are discussed with particular emphasis on etching.