Silicon carbonitride by remote microwave plasma CVD from organosilicon precursor: Growth mechanism and structure of resulting Si:C:N films

The remote microwave hydrogen plasma chemical vapor deposition (RP-CVD) from bis(dimethylamino)methylsilane precursor was used for the synthesis of silicon carbonitride (Si:C:N) films. The effect of thermal activation on the RP-CVD process was examined by determining the mass- and the thickness-based film growth rate and film growth yield, at different substrate temperature (TS). It was found that the mechanism of the process depends on TS and for low substrate temperature regime, 30 °C ≤ TS ≤ 100 °C, RP-CVD is limited by desorption of film-forming precursors, whereas for high substrate temperature regime, 100 °C < TS ≤ 400 °C, RP-CVD is a non-thermally activated and mass-transport limited process. The Si:C:N films were characterized by X-ray photoelectron and Fourier transform infrared spectroscopies, as well as by atomic force microscopy. The increase of TS enhances crosslinking in the film via the formation of nitridic Si-N and carbidic Si-C bonds. On the basis of the structural data a hypothetical crsosslinking reactions contributing to silicon carbonitride network formation have been proposed.