Damascene and dual damascene processes were developed as there is NO DRY etching for copper. The damascene process is oposite compare to the classical way of depositing and patterning of metal. Damascene is done by etching trenches, depositing a seed layer, electroplating copper in the trenches and CMP the surface to separate copper lines from each other. Pavel P.S. Wet etching proces is not suitable for micrometer lines and below. __________________________________ Do you Yahoo!? SBC Yahoo! DSL - Now only $29.95 per month! http://sbc.yahoo.com