In situ, real-time infrared absorption spectroscopy in the multiple internal reflection geometry was employed to investigate the evolution of hydrocarbon components deposited during plasma-enhanced chemical vapor deposition with a deuterated benzene source. We detected a peak attributed to the C-D stretching vibration of the deuterated phenyl group, which indicated a mode in which the benzene ring structure is retained on the substrate during the adsorption. The evolution of each peak during the plasma exposure suggests that the addition reaction occurs during the adsorption. Furthermore, we observed that with increasing substrate bias applied, the benzene ring structures in the film were disrupted and the amount of alkane components increased. This addition reaction proceeded on the film surface, regardless of the substrate bias.

Reactions involving hydrogen plasma and oxygen plasma with a self-assembled monolayer (SAM) of octadecyltrichlorosilane were investigated by infrared absorption spectroscopy in multiple internal reflection geometry. The rate of decrease of the CH 3 peak intensity is smaller than that of the CH 2 peak intensity when the SAM is exposed to hydrogen plasma. This is attributed to the formation of CH 3 components as intermediate states of the hydrogenation of the SAM during hydrogen plasma exposure. Peak intensities due to CH 2 and CH 3 components in the SAM decreased at the same rate during oxygen plasma exposure. C=O components, detected during plasma exposure, are indicated as the intermediate states of film oxidation.

Deposition process of amorphous carbon film during plasma enhanced chemical vapor deposition was investigated with "in-situ" and "real-time" infrared absorption spectroscopy in multiple internal reflection geometry. We can observe the peaks due to the CD of deuterated benzene molecules and that due to the CD in alkane. These facts indicate that there is a mode that the film grows with retaining the molecular structure of benzene. We also examine the increasing behaviour of two peak intensties with the plasma exposure time. The increasing rate of the peak, due to the CD of benzene decreased at longer exposure time, compared with that due to the CD in alkane. It is suggested that the amorphous carbon film is deposited through addition reaction of adsorbed benzene with benzene generated in the plasma.