Sputtered-dielectric capacitors

The use of thin layers of metal oxides as a capacitor dielectric is of considerable current interest in connection with miniaturization techniques. Most of the work on this subject has been concerned with vacuum evaporation, but the paper demonstrates that a stoichiometric metal-oxide film can be deposited by reactive sputtering and that this has superior dielectric properties. Details of the plant and experimental methods are given. Results obtained for silicon-dioxide films 0.1 ¿m thick are quoted. Capacitance yields were 0.03 ¿F/cm2. Power factors of approximately 0.005 and RC products up to 30000 ¿F were obtained. These films are thought to be suitable for 5V d.c. operation. The capacitor has characteristics generally similar to the silvered-mica type, and temperature characteristics within the range ¿180 to +200°C are presented.