SELECTIVITY AND COPPER CHEMICAL VAPOR-DEPOSITION

The question of selectivity (on metal vs. insulator) in the growth of copper thin films from organometallic precursors is addressed by studying the adsorption of Cu(hfac)(vtms) (where hfac = 1,1,1,5,5,5-hexafluoroacetylacetonate and vtms = vinyltrimethylsilane) on high surface area silica using transmission infrared spectroscopy. No deposition is observed on dehydrated SiO2. In the presence of adsorbed, hydrogen bonded OH (OD) groups (from the dissociative adsorption of either water or ethanol-d6), thin film growth is nucleated and selectivity is lost. In addition, temperature-programmed desorption is employed to study the bonding of a number of neutral ligands to Cu(100). This information is then used to correlate the activation energy for desorption with the observed selectivity of a series of Cu(I) beta-diketonates.