Note: Additionally refined new possibilities of plasma probe diagnostics

AbstractThe advantages of in-situ SIMS plasma probe diagnostics are highlighted in low pressure hydrocarbon ECR reactive ion etching (RIE) of III-V materials. Three aspects of the RIE process are investigated. First, the dominant ion species in a CH4/H2/Ar plasma are recorded at various chamber pressures, ECR powers, CH4/(CH4+H2) gas flow ratios and microwave cavity tuning. These studies have improved our understanding of the effects of these parameters on the relative concentrations of reactive precursor species in the plasma and have led to more rapid optimization of the etch system. Secondly, SIMS has been used for identification of reaction products from the III-V surface at the optimized plasma conditions. The Ar diluted mixture gives rise to significant levels of group V hydrides and organometallic compounds and the dominant group III volatile ions have been positively identified as dimethyl species. The third and final aspect reported is the application of volatile product identification to endpoint detection. In lcm2 multiple quantum well samples, layers as thin as 50Å are easily distinguishable.

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FINITE THICKNESS EFFECT OF PROBE SHEATH IN RADIO-FREQUENCY PLASMA PROBE DIAGNOSTICS

Le Journal de Physique Colloques ◽

10.1051/jphyscol:19797389 ◽

1979 ◽

Vol 40 (C7) ◽

pp. C7-807-C7-808

Author(s):

V. A. Godyak ◽

S. N. Ox

Keyword(s):

Radio Frequency ◽

Finite Thickness ◽

Thickness Effect ◽

Radio Frequency Plasma ◽

Probe Diagnostics ◽

Frequency Plasma ◽

Plasma Probe

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Note: Refined possibilities for plasma probe diagnostics

Review of Scientific Instruments ◽

10.1063/1.4960396 ◽

2016 ◽

Vol 87 (8) ◽

pp. 086106 ◽

Cited By ~ 3

Author(s):

P. E. Masherov ◽

V. A. Riaby ◽

V. K. Abgaryan

Keyword(s):

Probe Diagnostics ◽

Plasma Probe

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Note: The expansion of possibilities for plasma probe diagnostics

Review of Scientific Instruments ◽

10.1063/1.4948923 ◽

2016 ◽

Vol 87 (5) ◽

pp. 056104 ◽

Cited By ~ 4

Author(s):

P. E. Masherov ◽

V. A. Riaby ◽

V. K. Abgaryan

Keyword(s):

Probe Diagnostics ◽

Plasma Probe

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Comparative analyses of plasma probe diagnostics techniques

Journal of Applied Physics ◽

10.1063/1.4937446 ◽

2015 ◽

Vol 118 (23) ◽

pp. 233302 ◽

Cited By ~ 49

Author(s):

V. A. Godyak ◽

B. M. Alexandrovich

Keyword(s):

Comparative Analyses ◽

Probe Diagnostics ◽

Plasma Probe

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RF plasma probe diagnostics: a method for eliminating measurement errors for Langmuir probes with bare protective shields

Journal of Physics Conference Series ◽

10.1088/1742-6596/958/1/012006 ◽

2018 ◽

Vol 958 ◽

pp. 012006

Author(s):

V A Riaby ◽

P E Masherov ◽

V P Savinov ◽

V G Yakunin

Keyword(s):

Measurement Errors ◽

Rf Plasma ◽

Langmuir Probes ◽

Probe Diagnostics ◽

Plasma Probe

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Elevating the Precision of Plasma Probe Diagnostics by Elimination of Bare Probe Protective Shields’ Influence

Journal of Chemistry Education Research and Practice ◽

10.33140/jcerp/01/01/00003 ◽

2017 ◽

Vol 1 (1) ◽

Keyword(s):

Measurement Errors ◽

Plasma Electron ◽

Physical Analysis ◽

Bare Metal ◽

Langmuir Probes ◽

Plasma Parameters ◽

Probe Diagnostics ◽

Plasma Probe ◽

Shield Length ◽

Probe Measurements

Probe diagnostics of the low pressure inductive xenon plasma were conducted using classic cylindrical Langmuir probes with conventional protection of their circuits against radio frequency interferences by bare metal shields. The dimensions of their probetips were determined in the special experiment that provided negligible local plasma distortions. Accurate probe measurements were used to determine the spatial plasma parameter distributions in a gas discharge unit of an ion thruster model which helped to develop its ion-extracting grate. The subsequent analysis of probe measurements showed that in these experiments, the plasma electron energy distribution function (EEDF) was quite noticeably deviated from the Maxwell function depending on the main probe shield length that varied from maximum to zero. Use of an additional probe in the special position where its shield was rather long with zero shield length of the main probe showed that the additional shield lowered all plasma parameters. Comparison of both probes’ data identified the principled relationship between measurement errors and EEDF distortions caused by bare probe shield and this dependence was used to correct the initial probe measurements. Therefore plasma probe diagnostics became more precise due to the lowered influence of the bare probe protective shields. Its physical analysis based on previous authors’ works showed that this effect was caused by a shortcircuited double-probe phenomenon in the bare metal shields.

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