Damascene interconnection having porous low k layer with a hard mask reduced in thickness

摘要

A method is provided of fabricating a damascene interconnection. The method begins by forming on a substrate a first dielectric layer, a capping layer on the first dielectric sublayer and a resist pattern over the capping layer to define a first interconnect opening. The capping layer and the dielectric layer are etched through the resist pattern to form the first interconnect opening. The resist pattern is removed and a barrier layer is applied over the capping layer and in the first interconnect opening. An interconnection is formed by filling the first interconnect opening with conductive material. The interconnection is planarized to remove excess material and a portion of the first dielectric layer damaged by the planarizing step is selectively etched. A second dielectric layer is applied to replace the damaged portion of the first dielectric.