Ultrathin Ta2 O 5 Film Capacitor with Ru Bottom Electrode

Abstract

The characteristics of the ultrathin film capacitors with Ru bottom electrodes have been investigated. Ru films are deposited on by sputtering in 10% ambient, for the bottom electrode, and films are deposited by chemical vapor deposition using and . By plasma treatment at 400°C after thermal treatment at 700°C, excellent properties, are obtained such that the effective film thickness is 0.68 nm for 6 nm thick film and the leakage current is less than between the range of −2.1 and +1.8 V. The film with a Ru bottom electrode is one of the most suitable structures for Gbit dynamic random access memory capacitors.