Cold-cathode discharges and breakdown in argon: surface and gas phase production of secondary electrons

Plasma Sources Science and Technology

Volumn 8, Issue 3, 1999, Pages

  Phelps, A V ^a   Petrovic Z Lj ^a,b  

^a UNIVERSITY OF COLORADO   (United States)

^b UNIVERSITY OF BELGRADE   (Serbia)

Author keywords

[No Author keywords available]

Indexed keywords

ARGON; CARRIER MOBILITY; CATHODES; CHARGED PARTICLES; DENSITY (SPECIFIC GRAVITY); ELECTRIC BREAKDOWN; ELECTRIC DISCHARGES; ELECTRIC FIELD EFFECTS; ELECTRON ENERGY LEVELS; MATHEMATICAL MODELS; REACTION KINETICS; TRANSPORT PROPERTIES;

COLD CATHODE DISCHARGES; FEEDBACK AVALANCHES; SECONDARY ELECTRONS;

ELECTRONS;

EID: 0032690466     PISSN: 09630252     EISSN: None     Source Type: Journal    
DOI: 10.1088/0963-0252/8/3/201     Document Type: Article

References (208)

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58. -7 Torr.
59. -7 Torr.
60. -8 Torr.
61. -8 Torr.
62. -5 Torr.
63. -6 Torr.
64. -5 Torr.
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89. -10 Torr.
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91. -11 Torr.
92. -11 Torr.
93. -5 Torr.
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100. -8.
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102. -7 Torr.
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110. -7 Torr.
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120. -9 Torr.
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128. -1 Torr, where photoelectron feedback is expected to be small.
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138. -9. Probable purity of gas supply is 0.9999. Electrode spacing 0.3m to 1 cm.
139. 2 [134].
140. -7 Torr. Typical electrode spacings at breakdown were 0.5 cm. Electrodes exposed to ethane from mixture experiments.
141. -8 Torr.
142. -9 Torr. Electrodes conditioned with glow discharge to give reproducible results.
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165. +.
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169. 0 metastable state where the potential curves [133] suggest no collisional coupling to lower levels at 300 K and experiments show two and three-body collision loss [165, 166]. Fortunately, only 25% of the electron excitation is to these levels [17]. Most, but not all, of our rate coefficients for the lower six levels agree with those given by Millet et al [134]. We have not examined the transient solutions for our eight-level or our four-level model.
170. 2d and approximately as 1/Δλ at wavelength shifts Δλ from +0.6 to +30 nm, as expected for dipole-dipole collisional broadening. Over most of this range the normalized absorption is about twice that predicted by dipole-dipole broadening theory used in our resonance-radiation transport model [28]. At wavelengths closer to line centre the limited data approach the theory.
171. The calculations presented in this paper were carried out using Mathematica 3.0 © on a 300 MHz personal computer and required about 25 s per E/n value.
172. Details are available on request. Send email to avp@jila.Colorado.edu.
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176. For example, the determination of the steady-state breakdown and discharge maintenance pd at a given E/n would require interpolation between pd values for MC solutions yielding temporally growing and decaying discharge currents. Unfortunately, a recent application of MC techniques for a finite growth rate during pulsed breakdown appears to neglect the multiple avalanches required to observe breakdown [167]. The use of Monte Carlo techniques for the modelling of high current cathode fall discharges [5, 6] usually does not require multiple solutions because the nonlinear dependence of space-charge electric fields on current density means that one can often reach a steady-state current with an arbitrary choice of discharge voltage and pd.
177. -10 instead of zero.
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