For seedless electroplating of low resistivity Cu film applicable to deep submicrometer damascene feature, Pd activation was
introduced to direct Cu electroplating onto a high resistivity TiN barrier to get a high quality Cu film. Displacement-deposited Pd
particles on the TiN substrate acted as nucleation sites for Cu plating. This high-density instantaneous nucleation made it possible
to deposit a continuous, bright Cu film with low resistivity of 3.1 mV cm ~after annealing!. Aided by small amounts of benzotriazole,
Pd activation also gave way to the application of seedless plating to superfilling of a deep submicrometer damascene
structure, where the formation of the seed layer had been a critical issue. Poor adhesion between plated Cu and Pd activated TiN
substrate was greatly improved by the addition of poly~ethylene glycol!. The change in film characteristics was found to be
negligible
