LOW-PRESSURE CHEMICAL VAPOR-DEPOSITION OF COPPER - DEPENDENCE OF THE SELECTIVITY ON THE WATER-VAPOR ADDED TO A HYDROGEN OR HELIUM CARRIER GAS

The selectivity of copper deposition from copper (II) bis-hexafluoroacetylacetonate on SiO2 patterned with a platinum seeding layer is studied as a function of the reagent ps mixture. On platinum, the copper film growth rate increases with the amount of water vapor in the gas flow, and is independent of the chemical nature of the carrier gas used (H-2 or He). The selectivity of the copper deposition is significantly improved when using He rather than H-2 as carrier gas, especially at high water vapor concentrations where rapid film growth can be obtained.