Method for reactive ion etch processing of a dual damascene structure

摘要

A method for implementing dual damascene processing includes forming a first hardmask layer over an interlevel dielectric layer, and forming a second hardmask layer over the first hardmask layer. A trench pattern is opened within a third hardmask layer formed over the second hardmask. A first etch process is implemented so as to define a via pattern completely through the second hardmask layer and partially through the first hardmask layer, and a second etch process is implemented to transfer the trench pattern and the via pattern into the interlevel dielectric layer.