Modeling of electronegative radio-frequency discharges

Journal Article · Mon Apr 01 04:00:00 EST 1991 · IEEE Transactions on Plasma Science (Institute of Electrical and Electronics Engineers); (United States)

DOI:https://doi.org/10.1109/27.106805· OSTI ID:5827378

Meyyappan, M; Govindan, T R ^[1]

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1. Scientific Research Associates, Inc., Glastonbury, CT (United States)

In this paper a continuum model is presented for low-pressure, radio-frequency (RF) electronegative discharges commonly encountered in reactive ion etching and plasma-deposition applications. The model is based on the moments of the Boltzmann transport equations. Local and convective acceleration terms are retained in the momentum equations for the electrons and ions as it allows nonlocal transport in weakly collisional regions. A stable numerical scheme to solve these equations is also presented. A chlorine discharge at 13.56 MHz is simulated here as a case study. The simulation results reproduce features observed experimentally in Cl{sub 2} discharges under similar conditions. Of particular importance is the simulated excitation and ionization waveforms. In the bulk, the waveforms peak twice per cycle, which is essentially due to the modulation of electron temperature; in the sheath regions, the waveforms peak only during the anodic part of the cycle when the electrons are accelerated toward the electrode. The time-averaged ionization, excitation, and attachment rate profiles exhibit peaks near each sheath/plasma interface. The energy of the ions striking the electrodes is computed self-consistently. The ratio of ion energy to the average potential difference between the plasma and the electrodes is found to be 0.33.

• OSTI ID: 5827378
• Journal Information: IEEE Transactions on Plasma Science (Institute of Electrical and Electronics Engineers); (United States), Journal Name: IEEE Transactions on Plasma Science (Institute of Electrical and Electronics Engineers); (United States) Vol. 19:2; ISSN 0093-3813; ISSN ITPSB
• Country of Publication: United States
• Language: English

Related Subjects

42 ENGINEERING
426000* -- Engineering-- Components
Electron Devices & Circuits-- (1990-)
99 GENERAL AND MISCELLANEOUS
990200 -- Mathematics & Computers
BOLTZMANN EQUATION
CALCULATION METHODS
CHEMICAL REACTIONS
CHLORINE
COLLISIONAL PLASMA
DEPOSITION
DIFFERENTIAL EQUATIONS
ELECTRIC DISCHARGES
ELECTRONEGATIVITY
ELEMENTS
EQUATIONS
EQUATIONS OF MOTION
ETCHING
HALOGENS
HIGH-FREQUENCY DISCHARGES
LINEAR MOMENTUM
MATHEMATICAL MODELS
NONMETALS
NUMERICAL SOLUTION
PARTIAL DIFFERENTIAL EQUATIONS
PLASMA
PRESSURE DEPENDENCE
RF SYSTEMS
SIMULATION
SURFACE FINISHING
WAVE FORMS