Electrodes for optoelectronic thin-film devices must be conductive, optically transparent, and structurable by etching. The indium-tin-oxide (ITO) currently used fails to meet all these requirements. A new deposition sequence for ITO is therefore proposed. ITO films are grown reactively by magnetron sputtering from an indium/tin target. During the process, the oxygen partial pressure is varied periodically. We investigated the microstructure of these films by cross-sectional transmission electron microscopy (TEM) and show results of conductivity, optical absorption and etching behavior. © 1990.