High affinity self-assembled monolayers for copper CVD

Copper thin films were grown on SiO2 substrates by chemical vapor deposition using the precursor (MHY)Cu(hfac) and were examined by scanning electron microscopy. The affinity for copper chemical vapor deposition of the substrate surface is higher after the formation of self-assembled monolayers of 3-mercaptopropyltrimethoxysilane onto the substrate surface. Furthermore, the affinity is greatly enhanced by a subsequent UV-light irradiation of the organosilane monolayer, in air, prior to deposition. Hence, sticky copper films were obtained by copper CVD on flat and patterned surfaces. We have demonstrated by XPS that the initial surfacic thiol groups that have been oxidized into sulfonic type groups act as nucleation sites for copper CVD. (C) 2004 Elsevier B.V. All rights reserved.