When mica is exposed to a low temperature nonpolymer-forming plasma the surface structure is altered by a combination of sputtering and chemical reaction with reactive species in the plasma. The chemical composition of the surface is altered without a significant increase in surface roughness under optimal conditions. The effect of the plasma process parameters (exposure time, power, flow rate, and pressure) on the extent of surface modification has been investigated by means of ESCA and contact angle measurements. After exposure to water vapor plasma the mica surface becomes reactive to silanation with chlorosilanes in the gas phase. The durability of mica surfaces modified by plasma treatment and subsequent reaction with some chlorosilanes has been investigated. The forces between water plasmatreated surfaces after silanation have been measured using a surface force apparatus.
A603