Halogen based copper RIE - Influence of the material characteristics and deposition processes

As a consequence of the well-known difficulties in reactive dry Cu patterning only a small number of processes have been published world-wide. Using the low frequency biasing, as an alternative approach including an intense ion bombardment, the formation of thick sidewall films during etching (as proposed by other groups) is not necessary. As will be shown, the dimensional accuracy of the Cu pattern is strongly influenced by the metal deposition processes (PVD or CVD), barrier materials and interfaces. Also the electrical behaviour of Cu is influenced by material issues as could be proven for the line resistance.