REDUCING DEFECTS AND IMPROVING RELIABILITY OF BEOL METAL FILL

摘要

A method of reducing defects in and improving reliability of Back-End-Of-Line (BEOL) metal fill includes providing a starting metallization structure for semiconductor device(s), the metallization structure including a bottom layer of contact(s) surrounded by a dielectric material. The starting metallization structure further includes an etch-stop layer over the bottom layer, a layer of dielectric material over the etch-stop layer, a first layer of hard mask material over the dielectric layer, a layer of work function hard mask material over the first hard mask layer, a second layer of hard mask material over the work function hard mask layer, via(s) to the first hard mask layer and other via(s) into the etch-stop layer. The method further includes protecting the other via(s) while removing the second hard mask layer and the layer of work function hard mask material, and filling the vias with metal. Protecting the other via(s) may include, prior to the removing, filling the other via(s) with an Energy Removal Film (ERF) up to a top surface of the first hard mask layer, and, after the removing, removing the ERF material.

主权项

1. A method, comprising:
providing a starting metallization structure for one or more semiconductor devices, the metallization structure comprising a bottom layer of one or more contacts surrounded by a dielectric material, an etch-stop layer over the bottom layer, a layer of dielectric material over the etch-stop layer, a first layer of hard mask material over the dielectric layer, a layer of work function hard mask material over the first hard mask layer, a second layer of hard mask material over the work function hard mask layer, one or more first vias to the first hard mask layer and one or more second vias into the etch-stop layer; protecting the one or more second vias while removing the second hard mask layer and the layer of work function hard mask material; and filling the one or more first vias and the one or more second vias with metal.