A one-mask-patterned ferroelectric capacitor test structure designed with a 0.5-μm feature size was fabricated. Oxygen plasma treatment after dry etching decreased the leakage current to as low as that of as-deposited film. These one-mask-patterned ferroelectric capacitors, with switching charge almost equal to as-deposited film, were successfully fabricated. Ferroelectric memories as dense as dynamic random access memories will become possible with this technology. However, the leakage current density for micron-sized capacitors is 2 to 10 times that of large capacitors. The leakage current in small capacitors is increased due to perimeter leakage that runs through the damaged region on the capacitor sidewall. © Scripta Technica, Inc. Electr Eng Jpn, 121(1): 43–50, 1997