Tantalum Thin Film Applications – A New Approach for Capacitors

Abstract

Tantalum-based materials and process developments have increased the use of tantalum films, combined with silicon integrated circuits, to form hybrid integrated circuits which can meet the demands of telecommunication systems. This paper, after a historical review, describes the status of tantalum thin film technology used at Telettra in the implementation of circuits for telecommunication equipment. In particular, this paper focusses on the efforts devoted to the improvement of the β-Ta capacitor process in terms of yield and reliability for RC active filter realization. The results of a new Ta₂ O₅ –β Ta deposition process, where a Ta₂ O₅ layer is first formed by d.c. reactive sputtering in oxygen in the same vacuum batch where the β-Ta film is sequentially formed, are given.