Published online by Cambridge University Press: 15 February 2011
The substrate bias was applied during the chemical vapor deposition (CVD) process of copper in an effort to change the adsorption behaviors of the reactant. Copper films were deposited on TiN and SiO2 from Cu(hfac)(tmvs) with the substrate bias and without one. The surface morphology, the thickness, the sheet resistance and the purity of the films were investigated. When the negative substrate bias of -30 V was applied to the substrate, the deposition rate of copper increased both on TiN and SiO2. No change was observed in the chemical composition of the copper film deposited with substrate bias in comparison with that of the copper film deposited with no bias. It was calculated that Cu(hfac) has the dipole moment whose direction is from copper to hfac. Under the d. c.electric field, dipole tends to align along the poling direction. Resulting from the overlapping population (OP) value analysis, the improvement of deposition rate under negative substrate bias was explained due to the adsorption of copper atom in Cu(hfac) species directly onto the substrate by the electric field applied between the substrate and the gas showerhead.