International Business Machines Corporation
Ultrathin multilayer metal alloy liner for nano Cu interconnects

Abstract:

Compositions of matter, compounds, articles of manufacture and processes to reduce or substantially eliminate EM and/or stress migration, and/or TDDB in copper interconnects in microelectronic devices and circuits, especially a metal liner around copper interconnects comprise an ultra thin layer or layers of Mn alloys containing at least one of W and/or Co on the metal liner. This novel alloy provides EM and/or stress migration resistance, and/or TDDB resistance in these copper interconnects, comparable to thicker layers of other alloys found in substantially larger circuits and allows the miniaturization of the circuit without having to use thicker EM and/or TDDB resistant alloys previously used thereby enhancing the miniaturization, i.e., these novel alloy layers can be miniaturized along with the circuit and provide substantially the same EM and/or TDDB resistance as thicker layers of different alloy materials previously used that lose some of their EM and/or TDDB resistance when used as thinner layers.