About cookies on this site Our websites require some cookies to function properly (required). In addition, other cookies may be used with your consent to analyze site usage, improve the user experience and for advertising. For more information, please review your options. By visiting our website, you agree to our processing of information as described in IBM’sprivacy statement. To provide a smooth navigation, your cookie preferences will be shared across the IBM web domains listed here.
Publication
ECS J. Solid State Sci. Technol.
Paper
Application of Cu Reflow Process on Ru Liner for Advanced Nanoscale Interconnects
Abstract
A novel physical vapor deposition (PVD) Cu reflow process with chemical vapor deposition (CVD) Ru liner was optimized for 10 nm generation interconnects and beyond. For these and future device generations, void-free Cu interconnects are a key requirement, and the PVD Cu reflow process improvements reported here provide significant advancement in enabling excellent Cu reflow performance. The Ru liner exhibited much better Cu reflow performance than a Ta liner by effectively suppressing Cu agglomeration during the Cu reflow process, likely due to a better adhesion to Cu. Reflow temperature and Ru thickness (continuity) are critical parameters for achieving good Cu reflow performance, and this optimized Cu reflow process with Ru liner did not show line top voids or sidewall voids, which are the two major void types often observed at this dimension when pursuing Cu fill with the conventional Cu seed and Cu plating fill scheme. Furthermore, this novel Cu reflow process exhibited an electromigration (EM) performance enhancement due to having better Cu fill quality.