Numerical modelling of spatio-temporal patterns in a DC-driven gas discharge-semiconductor system

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2015
Özden, Gözde
In this thesis, numerical modelling of temporal and spatial pattern formation in the planar layered system, consisted of a DC driven planar gas discharge layer, coupled to high ohmic semiconductor layer, is carried out in 1D and 2D Cartesian geometry. Numerical model includes continuity equations for ions and electrons, the Poisson equation for the electric field, the energy balance equation for the background gas. The conditions correspond to a transition from the Townsend regime to the glow discharge. Calculations are performed for the nitrogen at medium pressure, using Comsol Multiphysics and Matlab packages. First, period doubling bifurcation of the system is observed within 1D model and related Lorenz maps are derived. Then, stable pattern formation is studied within 2D model. The effects of different modelling approaches, including the effect of heating of the background gas is examined.

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Citation Formats
G. Özden, “Numerical modelling of spatio-temporal patterns in a DC-driven gas discharge-semiconductor system,” M.S. - Master of Science, Middle East Technical University, 2015.