Infrared total internal reflection spectroscopy of dimethylcadmium on silicon

The surface chemistry of dimethylcadmium (DMCd) on silicon surfaces is monitored through changes in the infrared spectra of both chemically and physically adsorbed molecules. A technique involving total internal reflection of the IR probe beam was employed to isolate the surface‐molecule signal from that due to ambient gas‐phase molecules. Fourier‐transformed infrared spectra of DMCd on silicon were recorded in the region from 2.0 to 5.0 μm, where the CH vibrational modes of the molecule occur. Excimer laser irradiation of the molecules at 248 nm under conditions appropriate for Cd film deposition resulted in changes in the observed spectra due to dissociation of both surface and gas‐phase molecules.