Interconnect line selectively isolated from an underlying contact plug

Abstract

The present invention relates to selectively electrically connecting an electrical interconnect line, such as a bit line of a memory cell, with an associated contact stud and electrically isolating the interconnect line from other partially underlying contact studs for other electrical features, such as capacitor bottom electrodes. The interconnect line can be formed as initially partially-connected to all contact studs, thereby allowing the electrical features to be formed in closer proximity to one another for higher levels of integration. In subsequent steps of fabrication, the contact studs associated with memory cell features other than the interconnect line can be isolated from the interconnect line by the removal of a silicide cap, or the selective etching of a portion of these contact studs, and the formation of an insulating sidewall between the non-selected contact stud and the interconnect line.