Processing of dust particles in low-pressure plasmas G. Paeva, R.P. Dahiya*, E. Stoffels, W.W. Stoffels, G.M.W. Kroesen, Department of Physics, Eindhoven University of Technology, PO Box 513, 5600 MB Eindhoven * on leave from: Centre for Energy Studies, Indian Institute of Technology, New Delhi - 110016, India. E-mail: [email protected]web page www.phys.tue.nl/EPG/
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Processing of dust particles in low-pressure plasmas G. Paeva, R.P. Dahiya*, E. Stoffels, W.W. Stoffels, G.M.W. Kroesen, Department of Physics, Eindhoven.
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Processing of dust particles
in low-pressure plasmas
G. Paeva, R.P. Dahiya*, E. Stoffels, W.W. Stoffels, G.M.W. Kroesen,
Department of Physics, Eindhoven University of Technology,
PO Box 513, 5600 MB Eindhoven
* on leave from: Centre for Energy Studies, Indian Institute of Technology, New Delhi - 110016, India.
A schematic view of the setup. Particles are injected and trapped in the RF plasma. Coating is performed using a
magnetron sputter source at the top. For the void formation experiment the magnetron is replaced by a camera.
A schematic view of the setup. Particles are injected and trapped in the RF plasma. Coating is performed using a
magnetron sputter source at the top. For the void formation experiment the magnetron is replaced by a camera.
SETUPSETUP
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nsity
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u.)
Left: The fluorescent spectrum of the BAM particles in an Ar plasma. The fluorescence is induced by the UV radiation from the plasma.
Right: Optical spectrum during Cu coating process in Ar using an external Hg lamp as a light source. The broad band reflects the BAM fluorescence from uncoated particles. Simultaneously, Hg-lines are visible due to Mie scattering.
Left: The fluorescent spectrum of the BAM particles in an Ar plasma. The fluorescence is induced by the UV radiation from the plasma.
Right: Optical spectrum during Cu coating process in Ar using an external Hg lamp as a light source. The broad band reflects the BAM fluorescence from uncoated particles. Simultaneously, Hg-lines are visible due to Mie scattering.
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Problem:There is some decrease in the fluorescence from the BAM particles even in pure Argon plasma. Probably due to VUV degradation of the BAM particles.
Calibration in Ar needed Other fluorescent particles
Problem:There is some decrease in the fluorescence from the BAM particles even in pure Argon plasma. Probably due to VUV degradation of the BAM particles.
Calibration in Ar needed Other fluorescent particles
Time dependence of scattering and fluorescence signal.•The scattering signal reflects particle density.
•The fluorescence signal reflects uncoated particle surface.
•The faster decay of the fluorescence indicates particle coating.
Time dependence of scattering and fluorescence signal.•The scattering signal reflects particle density.
•The fluorescence signal reflects uncoated particle surface.
•The faster decay of the fluorescence indicates particle coating.
uncoatedcoated
Particles coated with sputtered aluminium.Particles coated with sputtered aluminium.
(left) crystalline structure and (right) 7mm diameter void in the dust cloud in RF plasma sheath. Ring electrode (30 mm diameter) is visible on the periphery. The pictures of 9.8 m diameter MF are recorded by camera looking from the top of the experimental system, which is normal to the page.
(left) crystalline structure and (right) 7mm diameter void in the dust cloud in RF plasma sheath. Ring electrode (30 mm diameter) is visible on the periphery. The pictures of 9.8 m diameter MF are recorded by camera looking from the top of the experimental system, which is normal to the page.
2-D VOID FORMATION2-D VOID FORMATION
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Left: Inner (ID) and outer diameter (OD) of particle ring in argon RF plasma sheath and the position of a single bigger size particle at lower horizontal plane (right hand scale).
Right: Surface of the particle cloud
Left: Inner (ID) and outer diameter (OD) of particle ring in argon RF plasma sheath and the position of a single bigger size particle at lower horizontal plane (right hand scale).