Double layer formation in the expanding region of an inductively coupled electronegative plasma
نویسندگان
چکیده
Double-layers sDLsd were observed in the expanding region of an inductively coupled plasma with Ar–SF6 gas mixtures. No DL was observed in pure argon or SF6 fractions below a few percent. They exist over a wide range of power and pressure although they are only stable for a small window of electronegativity stypically between 8% and 13% of SF6 at 1 mTorrd, becoming unstable at higher electronegativity. They seem to be formed at the boundary between the source tube and the diffusion chamber and act as an internal boundary fthe amplitude being roughly 1.5skTe /edg between a high electron density, high electron temperature, low electronegativity plasma upstream sin the sourced, and a low electron density, low electron temperature, high electronegativity plasma downstream. © 2005 American Institute of Physics. fDOI: 10.1063/1.1869533g
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