An ECR MOCVD (Ba,Sr)TiO/sub 3/ based stacked capacitor technology with RuO/sub 2//Ru/TiN/TiSi/sub x/ storage nodes for Gbit-scale DRAMs

Abstract

A high dielectric constant (Ba,Sr)TiO/sub 3/ [BST] based stacked capacitor with new RuO/sub 2//Ru/TiN/TiSi/sub x/ storage nodes was developed for Gbit-scale DRAMs. Good insulating BST films with a small t/sub eq/ of 0.65 nm on the electrode sidewalls were obtained by ECR MOCVD. The four-layer storage node allows 500/spl deg/C processing and fine-patterning down to 0.20 /spl mu/m by EB lithography and RIE. A cell capacitance of 25 fF in 0.125 /spl mu/m/sup 2/ is achieved using 0.3 /spl mu/m-high storage electrodes for 1 Gbit DRAMs.