Method for achieving copper fill of high aspect ratio interconnect features

摘要

One aspect of the invention provides a consistent metal electroplating technique to form void-less metal interconnects in sub-micron high aspect ratio features on semiconductor substrates. One embodiment of the invention provides a method for filling sub-micron features on a substrate, comprising reactive precleaning the substrate, depositing a barrier layer on the substrate using high density plasma physical vapor deposition; depositing a seed layer over the barrier layer using high density plasma physical vapor deposition; and electro-chemically depositing a metal using a highly resistive electrolyte and applying a first current density during a first deposition period followed by a second current density during a second period.