The surface finish of plasma polymers deposited in an inductively coupled discharge were measured as a function of gas flow rates. Surface finish was measured both optically and by AFM. The process parameters of the plasma polymerization were found to effect the surface finish. The gases used were trans-2- butene and hydrogen for hydrocarbon polymers. For bromocarbon polymers we added ethylbromide. The smoothest hydrocarbon polymer coatings had an RMS surface finish better than 1 nm. Bumps 200 nm high spaced approximately 1 {mu}m apart grew on the surface of bromocarbon coatings when they were exposed to air. The composition of the bumps was found to be NH{sub 4}Br by XRD and XPS analysis. We believe that nitrogen (from a small leak or desorption) dissociates in the discharge and reacts with hydrogen to form ammonia. The ammonia then reacts with HBr, a dissociation product of ethylbromide, to form NH{sub 4}Br which is dispersed throughout the deposited layer. Humidity facilitates the transport of the NH{sub 4}Br to the surface where it crystallizes. Bump growth was prevented by either dry storage or overcoating with 3 {mu}m of hydrocarbon plasma polymer. Alternatively, the bumps could be washed from the surface with water.

Plasma polymerized organic coatings are used in the fabrication of targets for experiments in the Inertial Confinement Fusion (ICF) program at Lawrence Livermore National Laboratory. The authors are performing experiments to understand the process conditions leading to the preparation of smooth ({approx}100{Angstrom}) plasma polymer surfaces while maintaining the highest deposition rate possible. It had been reported by Howling et al., that the formation of particulate matter in the deposition of silicon by the plasma reaction of silane affected the plasma impedance. This suggested that experiments designed to examine the correlation of surface texture with plasma impedance would be of interest. Furthermore, it is possible that an impedance change may cause a change in the power coupling efficiency from the transmitter to the plasma. Preliminary work in the authors laboratory indicated that the reactor temperature influenced the surface texture. The focus of this paper is to carefully examine the effects of reactor temperature on the surface texture of the plasma polymer, ensuring constant reactor conditions especially with respect to rf power.