An electronic device of the type including a thin film body having a superposed electrode has short circuit defects therein passivated by a conversion process in which the electrical resistivity of the electrode material is increased proximate the defect regions. Conversion is accomplished by exposing the electrode material to a conversion reagent and activating the reagent proximate the defect regions. The process may be utilized for a variety of differently configured devices, and may be readily adapted for use in a roll-to-roll device fabrication process.