Year: 2002
Type: dissertation
Abstract: The presented thesis deals with various aspects of models for low pressure discharges. As well the theoretical background of hydrodynamic plasma models as the comparison of calculated data with experimental results are discussed. In the first part of this work hydrodynamic conservation equations are derived from the Boltzmann equation. Main focus is the application to low pressure plasmas. Different model systems for electrons and ions are presented. The question in which case simplified models can be applied, is treated as well as numerical aspects and algorithms for obtaining a solution are discussed. In a second part hydrodynamic models were used for performing one-dimensional simulations. The sensitivity of the model in dependence of input parameters like momentum exchange frequencies was analysed. As well different model systems were compared qualitatively in order to get an estimate for the error introduced by using simple and numerical more stable model systems. In the third part hydrodynamic models were applied to simulate different kinds of low pressure discharges. Main focus were inductively driven plasmas like they are used in semiconductor fabrication as high density plasma source. Calculated data for this kind of discharge were compared with experimental values obtained from Langmuir probe measurements. Theory and experiment show very good agreement. In a final part the scaling laws and geometry dependence derived from hydrodynamic models were used to assemble a set of general reactor design rules. Examples were presented, how reactor performance can be optimised by careful choice of geometry parameters. Also general dependencies on external parameters like discharge pressure were discussed.
Author: P. Scheubert
Language: English
Subfield: Electrical and Electronic Engineering
Field: Engineering
Domain: Physical Sciences
Open Access status: green
OpenAlex ID: W134369041