Modeling of miniature microwave plasma sources

Summary form only given. Interest in the development of systems on a chip, MEMS and their related microsystem applications, has suggested the possibility of numerous applications for miniature plasma sources. Accordingly, this investigation is devoted to developing models that improve the understanding of small microwave plasma sources. Methods of creating and controlling miniature microwave discharges that operate with low input power levels are being investigated. One aspect of this investigation is a numerical modeling effort on small microwave plasma sources that create plasmas with sizes in the range of submillimeter to a few millimeters. Microwave plasma systems based on microstripline structures and monopole antenna structures are being experimental constructed and measured, as well as, being modeled. The modeling work is the objective of this paper. Both bounded and unbounded microwave discharge systems are studied. The modeling effort uses either one- and two-dimensional self-consistent solutions of Maxwell equations and the plasma discharge equations to solve for the discharge behavior. This model was initially developed for larger discharge systems and is applied to the miniature microwave discharges in this study. The plasma discharge equations solved include the particle and energy balance equations, as well as, the electron Boltzmann equation. Miniature microwave discharge experimental data and modeling results are generated across a range of input parameters, including pressure variation from below 0.1 Torr to 50 Torr, input power at 2.45 GHz from one watt to 100 watts, and a variety of gases including argon and hydrogen. Microwave plasmas of various sizes (volumes) and aspect ratios are studied. The experimental and modeling results are used to identify the operating regime necessary to excite and maintain stable, miniature microwave plasmas.