COPPER CHEMICAL-VAPOR-DEPOSITION USING COPPER(I) HEXAFLUOROACETYLACETONATE TRIMETHYLVINYLSILANE

The effects of the deposition temperature on the microstructure and th e electrical resistivity of copper films prepared by chemical vapour d eposition (CVD) were studied at the deposition temperatures between 16 0 degrees C and 330 degrees C. Copper films were prepared on titanium nitride (TiN) substrates in a low-pressure warm-wall reactor using cop per(I) hexafluoroacetylacetonate trimethylvinylsilane, Cu (hfac) (TMVS ), as the precursor. The activation energy for the deposition was foun d to be 45.4 kJ mol(-1) at the total pressure of 66.7 Pa. The films de posited at below 200 degrees C, where the deposition is limited by sur face reaction, were dense and had low resistivity of approximately 2 m u Omega cm. Moreover, they exhibited excellent step coverage. However, the films deposited at above 200 degrees C, where the mass transport processes become important, were composed of poorly connected globular grains, resulting in considerably high resistivities and rough surfac es. Effects of the deposition temperature on the grain size and the pr eferred orientation of the films were also investigated.