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Abstract The Quantemol database (QDB) provides cross sections and rates of processes important for plasma models; heavy particle collisions (chemical reactions) and electron collision processes are considered. The current version of QDB has data on 28 917 processes between 2485 distinct species plus data for surface processes. These data are available via a web interface or can be delivered directly to plasma models using an application program interface; data are available in formats suitable for direct input into a variety of popular plasma modeling codes including HPEM, COMSOL, ChemKIN, CFD-ACE+, and VisGlow. QDB provides ready assembled plasma chemistries plus the ability to build bespoke chemistries. The database also provides a Boltzmann solver for electron dynamics and a zero-dimensional model. Thesedevelopments, use cases involving O2, Ar/NF3, Ar/NF3/O2, and He/H2O/O2chemistries, and plans for the future are presented.
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Transformer coupled toroidal wave-heated remote plasma sources operating in Ar/NF 3 mixtures
Abstract Remote plasmas are used in semiconductor device manufacturing as sources of radicals for chamber cleaning and isotropic etching. In these applications, large fluxes of neutral radicals (e.g. F, O, Cl, H) are desired with there being negligible fluxes of potentially damaging ions and photons. One remote plasma source (RPS) design employs toroidal, transformer coupling using ferrite cores to dissociate high flows of moderately high pressure (up to several Torr) electronegative gases. In this paper, results are discussed from a computational investigation of moderate pressure, toroidal transformer coupled RPS sustained in Ar and Ar/NF3mixtures. Operation of the RPS in 1 Torr (133 Pa) of argon with a power of 1.0 kW at 0.5 MHz and a single core produces a continuous toroidal plasma loop with current continuity being maintained dominantly by conduction current. Operation with dual cores introduces azimuthal asymmetries with local maxima in plasma density. Current continuity is maintained by a mix of conduction and displacement current. Operation in NF3for the same conditions produces essentially complete NF3dissociation. Electron depletion as a result of dissociative attachment of NF3and NFxfragments significantly alters the discharge topology, confining the electron density to the downstream portion of the source where the NFxdensity has been lowered by this dissociation.
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- Award ID(s):
- 2032604
- PAR ID:
- 10529892
- Publisher / Repository:
- IOP Publishing
- Date Published:
- Journal Name:
- Journal of Physics D: Applied Physics
- Volume:
- 57
- Issue:
- 43
- ISSN:
- 0022-3727
- Format(s):
- Medium: X Size: Article No. 435202
- Size(s):
- Article No. 435202
- Sponsoring Org:
- National Science Foundation
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