Radiation of an Electric Dipole in a Three Layered Plasma Structure

Ali Arshadi, Thomas Mussenbrock, Ralf Peter Brinkmann

WELT­PP-15, Kerk­ra­de, The Nether­lands, 22-23 No­vem­ber 2012


Reactive plasmas are widely used for materials processing, especially in etching and deposition applications. The electron density is an important parameter for the understanding of plasma sources and plasma processing. Of the many available Plasma diagnostics techniques, only few are suitable for an industrial and commercial setting. Typical methods to measure the electron density are the Langmuir probe and the microwave interferometer. As is well known, the Langmuir probe has certain problems in processing plasmas and rf plasma sources. In this contribution we study the radiation of an electric dipole in a three-layered structure (dielectric, sheath and bulk plasma) as the simplest microwave (but still complicated to analyse) probe and as the fundamental part of a real microwave probe. In fact the electromagnetic field of a dipole can be considered as the Green's function of a real system. We compute this Green function in the form of an integral whose integrand oscillates very fast and as a result some special mathematical techniques have to be applied in order to obtain the electromagntic fields of dipole in a layered system of plasma. Financial

Tags: Electric dipole, Green's function, Stratified plasma