Nam-Sik Yoon

A Global Simulation of SiH 4 /H 2 Discharge in a Planar-type Inductively Coupled Plasma Source

A global simulation of discharge is conducted in a planar-type inductively coupled plasma (ICP) discharge. We numerically solve a set of spatially averaged fluid equations for electrons, positive ions, negative ions, neutrals, and radicals. Absorbed power by electrons is determined by an analytic electron heating theory including the anomalous skin effect. Also, we investigate functional dependence of various discharge quantities such as the densities of various species and the temperature of electron on external controllable parameters such as ratio between and , power and pressure.

A feed-back control approach for global simulation of high density plasma discharges

Abstract Spatially averaged global simulations have been widely used to study discharge characteristics of high density plasma discharge, because the global insight on the dependence of quantities such as densities and temperatures can be obtained. Above all, the global model can quickly predict the plasma parameters on the external or the chamber parameters comparing with multi-dimensional modeling. However, the global model can be expensive to compute the plasma parameters for complex or mixed gas discharges. Therefore, in this work, we applied a feed-back approach to solve a set of spatially averaged fluid equations for charged particles, neutrals, and radicals. The results were shown that the developed model could efficiently enhance convergence of simulations.

A hybrid solution of non-uniform planar-type inductively coupled plasma-heating problem

Previous solution of RF (radio frequency) heating problem in ICP (inductively coupled plasma) production was obtained by an analytic mode of analysis for the entire region of source chamber. In this work, antenna region is treated by an analytic technique and a numerical solution for plasma region is obtained. Since antenna region is not fully solved, computing time is significantly saved and non-uniform plasma parameters can be easily considered by adopting the numerical method in the plasma region. In this calculation, some results for solenoidal-type ICP are obtained and compared with the previous fully analytic results (Yoon et al., Phy. Rev. E55(6) (1997) 7536). Also, calculations of local field profiles and plasma impedance for non-uniform plasma are compared with each other. These results are somewhat different trend from planar case (Yoon et al., Thin Solid Films, 2002).

Calculation of the Reactor Impedance of a Planar-type Inductively Coupled Plasma Source

A two-dimensional nonlocal heating theory of planar-type inductively coupled plasma source has been previously reported with a filamentary antenna current model. However, such model yields an infinite value of electric field at the antenna position, resulting in the infinite self-inductance of the antenna. To overcome this problem, a surface current model of antenna should be adopted in the calculation of the electromagnetic fields. In the present study, the reactor impedance is calculated based on the surface current model and the dependence on various discharge parameters is studied. In addition, a simpler method is suggested and compared with the surface current calculation.

A Three-Dimensional Calculation of the Reactor Impedance for Planar-Type Cylindrical Inductively Coupled Plasma Sources

The reactor impedance is calculated for a planar-type cylindrical inductively coupled plasma source by expanding the electromagnetic fields into their Fourier-Bessel series forms including the three-dimensional shape of the antenna. The mode excitation method is utilized to determine the electromagnetic fields based on a Poynting theoremlike relationship. From the obtained electromagnetic fields, a tractable form of the reactor impedance is obtained as a function of various plasma and geometrical parameters and applied to carry out a parametric study.

Numerical Investigation of Ion and Radical Density Dependence on Electron Density and Temperature in Etching Gas Discharges

Dependence of radical and ion density on electron density and temperature is numerically investigated for /Ar, , , , , and discharges which are widely used for etching process. We derived a governing equation set for radical and ion densities as functions of the electron density and temperature, which are easier to measure relatively, from continuity equations by assuming steady state condition. Used rate coefficients of reactions in numerical calculations are directly produced from collisional cross sections or collected from various papers. If the rate coefficients have different values for a same reaction, calculation results were compared with experimental results. Then, we selected rate coefficients which show better agreement with the experimental results.

3D fluid simulation of rectangular TCP source

Summary form only given, as follows. Large area rectangular TCP (transformer coupled plasma) sources have been widely applied to manufacture processes of display devices such as LCD (liquid crystal display) and PDP (plasma display panel). In the present, work, a three-dimensional fluid simulator of rectangular TCP source is developed. Two fluid equations for charged particles are solved numerically using the dielectric relaxation scheme and FDM (finite difference method). The electron heating model, which yields local power absorption profile for electron temperature equation, is constructed based on the Maxwell-Boltzmann equations and a simplified plasma surface impedance. Various simulation results of charged particle densities, electron temperature, and electrostatic potential are obtained and presented for argon discharge under various conditions of RF (radio frequency) power and neutral gas pressure.

An equivalent circuit model of HANBIT RF-Heating system

Summary form only given, as follows. An equivalent circuit model of HANBIT RF (radio frequency) heating system is developed. The present circuit model includes transmission line, impedance matching network and reactor impedance. The reactor impedance is a sum of plasma impedance and antenna impedance including the stray impedance. The plasma impedance and antenna impedance are calculated utilizing a solution of the Maxwell-Boltzmann equation obtained under the RF-heating condition. The stray impedance includes the ohmic power loss on the reactor chamber. Based on the developed circuit model, dependence of power absorption on the various plasma parameters is investigated in the perfect matching case. In the imperfect matching case, reflection coefficient and reflectance of RF-electromagnetic wave are calculated as functions of various geometric and plasma parameters.