Interconnect structure for improved time dependent dielectric breakdown

摘要

The present disclosure provides a method of forming an interconnect to an electrical device. In one embodiment, the method of forming an interconnect includes providing a device layer on a substrate, wherein the device layer comprises at least one electrical device, an intralevel dielectric over the at least one electrical device, and a contact that is in electrical communication with the at least one electrical device. An interconnect metal layer is formed on the device layer, and a tantalum-containing etch mask is formed on a portion of the interconnect metal layer. The interconnect metal layer is etched to provide a trapezoid shaped interconnect in communication with the at least one electrical device. The trapezoid shaped interconnect has a first surface that is in contact with the device layer with a greater width than a second surface of the trapezoid shaped interconnect that is in contact with the tantalum-containing etch mask.