This proposal is for continuation of research on r.f. plasma discharges for use in materials processing of microelectronic circuits. The program involves (a) the development of an electron beam probe and other plasma diagnostics to measure discharge electric fields, species densities, and other parameters; and (b) the development of analytical discharge models and numerical codes to explore the variation of plasma and sheath parameters with control variables. The electron beam probe measurements will be compared to tuned high- impedance Langmuir probe and microwave density measurements, voltage, current and r.f. power measurements. These results will be compared with the predictions of the analytical, asymmetric discharge models and used to guide further model development. The analytical modeling of capacitive r.f. discharges will be extended to asymmetric discharge geometries. A spherical shell model that is in the initial stage of development will be further developed and used to compare with experiments. The model will be extended to finite length cylindrical and coaxial geometries that are used in industry. Magnetic enhancement of r.f. discharges will be modeled. The results will be incorporated into a computer code. Experimental measurements and results of computer simulation will be used to guide the further development of the analytical models and codes.