Threshold studies of secondary electron emission induced by macro-ion impact on solid surfaces

Abstract One-dimensional particle-in-cell/Monte Carlo collisional (PIC/MCC) simulations are performed on a capacitive 2.54 cm gap, 1.6 Torr argon discharge driven by a sinusoidal rf current density amplitude of 50 A/m2 at 13.56 MHz. The excited argon states (metastable levels, resonance levels, and the 4p manifold) are modeled self-consistently with the particle dynamics as space- and time-varying fluids. Four cases are examined, including and neglecting excited states, and using either a fixed or energy-dependent secondary electron emission yield due to ion and/or neutral impact on the electrodes. The results for all cases show that most of the ionization occurs near the plasma-sheath interfaces, with little ionization within the plasma bulk region. Without excited states, secondary electrons emitted from the electrodes are found to play a strong role in the ionization process. When the excited states, secondary electron emission due to neutral and ion impact on the electrodes are included in the discharge model, the discharge operation transitions from α-mode to γ-mode, in which nearly all the ionization is due to secondary electrons. Excited states are very effective in producing secondary electrons, with approximately 14.7 times the contribution of ion bombardment. Electron impact of ground state argon atoms by secondary electrons contributes about 76 % of the total ionization; primary electrons, about 11 %; metastable Penning ionization, about 13 %; and multi-step ionization, about 0.3 %.

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Forward/backward secondary electron emission from foils by swift ion impact

Nuclear Instruments and Methods in Physics Research Section B Beam Interactions with Materials and Atoms ◽

10.1016/0168-583x(94)95614-6 ◽

1994 ◽

Vol 90 (1-4) ◽

pp. 560-563 ◽

Cited By ~ 2

Author(s):

Toshiaki Kaneko ◽

Yuji Mitsunobu

Keyword(s):

Electron Emission ◽

Secondary Electron ◽

Secondary Electron Emission ◽

Ion Impact

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Factors affecting the performance of detectors that use secondary electron emission from a thin foil to determine ion impact position

Nuclear Instruments and Methods in Physics Research Section A Accelerators Spectrometers Detectors and Associated Equipment ◽

10.1016/s0168-9002(99)01444-8 ◽

2000 ◽

Vol 449 (1-2) ◽

pp. 396-407 ◽

Cited By ~ 19

Author(s):

D Shapira ◽

T.A Lewis ◽

L.D Hulett ◽

Z Ciao

Keyword(s):

Electron Emission ◽

Secondary Electron ◽

Secondary Electron Emission ◽

Thin Foil ◽

Factors Affecting ◽

Impact Position ◽

Ion Impact

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Untersuchungen zur Auftreffwinkelabhängigkeit des Emissionskoeffizienten für Sekundärelektronen und der Zerstäubungsausbeute beim Ionenbeschuß zylindrischer Proben im Plasma / Investigation of the Angular Dependence of the Secondary Electron Emission Coefficient and the Sputtering Yield by Ion Bombardment of Cylindrical Targets in a Plasma

Zeitschrift für Naturforschung A ◽

10.1515/zna-1969-1208 ◽

1969 ◽

Vol 24 (12) ◽

pp. 1908-1914

Author(s):

H Oechsner ◽

W Gesang

Keyword(s):

Electron Emission ◽

Secondary Electron ◽

Secondary Electron Emission ◽

Solid Surfaces ◽

Angle Of Incidence ◽

Emission Coefficient ◽

Secondary Electron Emission Coefficient ◽

Cylindrical Target ◽

Sputtering Yield ◽

Low Energy Ions

The influence of the angle of incidence of low energy ions on the emission of secondary particles from solid surfaces can be investigated by using cylindrical targets in a low pressure plasma. It is shown that the distribution of the angle of incidence of the impinging ions becomes independent of plasma conditions and bombarding parameters, when the diameter of the Langmuir sheath around the target is sufficiently large compared with that of the cylindrical target. Experimental results on the influence of the angle of ion incidence on the secondary electron emission coefficient and the sputtering yield are reported for polycrystalline Mo bombarded with A+-ions from 300 to 900 eV.

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