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Electron impact cross sections sets are constructed for the nitrogen trifluoride, nitrogen difluoride and nitrogen monofluoride molecules. These cross sections are based on ab initio R-matrix calculations augmented by other procedures. Cross sections are presented for elastic collisions, momentum transfer, dissociative electron attachment, electron impact dissociation, ionisation and dissociative ionisation. For NF process occurring via the metastable a D 1 and b S + 1 states are also considered. A semi-empirical method of estimating the products of electron impact ionisation is proposed and tested for ammonia. The cross sections are extended to high energy where appropriate. The cross section set constructed is tested in a global model simulation of a low pressure, inductively coupled plasma based on a Ar/NF 3 /O 2 initial gas mixture.

Plasma etching of high aspect ratio (HAR) features, typically vias, is a critical step in the fabrication of high capacity memory. With aspect ratios (ARs) exceeding 50 (and approaching 100), maintaining critical dimensions (CDs) while eliminating or diminishing twisting, contact-edge-roughening, and aspect ratio dependent etching (ARDE) becomes challenging. Integrated reactor and feature scale modeling was used to investigate the etching of HAR features in SiO 2 with ARs up to 80 using tri-frequency capacitively coupled plasmas sustained in Ar/C 4 F 8 /O 2 mixtures. In these systems, the fluxes of neutral radicals to the wafer exceed the fluxes of ions by 1-2 orders of magnitude due to lower threshold energies for dissociation compared with ionization. At low ARs (<5), these abundant fluxes of CF x and C x F y radicals to the etch front passivate the oxide to form a complex which is then removed by energetic species (ions and hot neutrals) through chemically enhanced reactive etching, resulting in the formation of gas phase SiF x , CO x , and COF. As the etching proceeds into higher ARs, the fractional contribution of physical sputtering to oxide removal increases as the fluxes of energetic species to the etch front surpass those of the conduction constrained CF x and C x F y radicals. The instantaneous etch rate of oxide decreases with increasing aspect ratio (ARDE effect) due to decreased fluxes of energetic species and decreased power delivered by these species to the etch front. As the etch rate of photoresist (PR) is independent of AR, maintaining CDs by avoiding undercut and bowing requires high SiO 2-over-PR selectivity, which in turn requires a minimum thickness of the PR at the end of etching. Positive ions with narrow angular distributions typically deposit charge on the bottom of low AR features, producing a maximum in positive electric potential on the bottom of the feature. For high AR features, grazing incidence collisions of ions on sidewalls depositing charge produce electric potentials with maxima on the sidewalls (as opposed to the bottom) of the feature.

These data show that HBOT alleviates CCI-induced neuropathic pain and inhibits endoneuronal TNF-α production, but not IL-1β in CCI-induced neuropathic pain. Reduced TNF-α production may, at least in part, contribute to the beneficial effect of HBOT.

Here we demonstrate the oopd1 (object-oriented plasma device for one dimension) particle-in-cell/Monte Carlo simulation tool for a capacitively coupled chlorine discharge with a comprehensive reaction set. We apply a hybrid approach where a global model determines the dissociation fraction of the discharge. The simulation results are compared with available experimental measurements and good agreement is achieved. We explore a typical capacitively coupled chlorine discharge using oopd1 and obtain key plasma parameters, including particle density, effective electron temperature, electron energy probability function and ion energy and angular distributions for both Cl + and Cl + 2 ions. The dependence of the plasma parameters on the discharge pressure is systematically investigated. As the pressure increases from 5 to 100 mTorr, the heating mechanism evolves from both stochastic and Ohmic heating to predominantly Ohmic heating and the electron heating outweighs the ion heating at high pressures. Also, the density profile for Cl + 2 and Cl − ions becomes flat in the bulk region and the electronegativity increases with increasing pressure. The creation of Cl + ions in the sheath region is mainly due to conversion from Cl + 2 ions to Cl + ions through non-resonant charge exchange, while in the bulk region the creation of Cl + ions is mainly ascribed to electron impact ionization processes.