Performances of several single gap (gas gap 2 mm) prototype Resistive PlateChambers (RPC) made of high resistive ({\rho} \sim 1010 - 1012 {\Omega} cm)bakelite, commercially available in India have been studied in recent times. Tomake the inner electrode surfaces smooth, a thin coating of silicone has beenapplied. An efficiency > 90% and time resolution \sim 2 ns (FWHM) have beenobtained for both the streamer and the avalanche mode. The induced chargedistributions of those silicone coated RPC are studied and the results arepresented. A numerical study on the effect of surface roughness of theresistive electrodes on the electric field of the device has been carried outusing Garfield-neBEM code. A few results for a simplified model representingsurface roughness, measured using a surface profilometer for the bakelitesurfaces, have also been presented.
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