Energy distribution function electron

Gorse C and Capitelli M 1996 Non-equilibrium vibrational, electronic and dissociation kinetics in molecular plasmas and their coupling with the electron energy distribution function NATO ASI Series C 482 437-49... 

Figure 13. Electron energy distribution functions of a CH4/H2 plasma as a function of pressure, (a) 50 mTorr. (b) 40 mTorr. (c) 30 mTorr. (d) 20 mTorr. (e) 10 mTorr. Reprinted with permission from [88], K. Okada et al., J. Vac. Sci. TechnoL, A 17, 721 (1999). 1999, American Institute of Physics.

Electron energy distribution function The distribution function of electrons in a plasma. That of a low-pressure radiofrequency plasma generally consists of two Maxwellian distributions, that is, fast and slow electrons. 

For low-pressure plasmas containing mainly inert gases the electrons can be characterized by a Maxwellian electron energy distribution function (EEDF). How-... 

In Equation 3, e and m are the impinging electron energy and mass, (e) is the reaction cross section, and / (e) is the electron energy distribution function. Of course, if an accurate expression for fie) and if electron collision cross sections for the various gas phase species present are known, k can be calculated. Unfortunately, such information is generally unavailable for the types of molecules used in plasma etching. 

Figure 5. Electron energy distribution functions for various gases and gas mixtures. (Reproduced with permission from Ref 24 J...

A time-varying electron energy distribution function (EEDF) was calculated from the Boltzmann equation. For convenience, all of the free electrons were placed near 5keV to approximate an initial nonequilibrium EEDF. The population densities were given by the time-dependent solution to the rate... 

Plasmas typical of C02 laser discharges operate over a pressure range from 1 Torr to several atmospheres with degrees of ionization, that is, nJN (the ratio of electron density to neutral density) in the range from 10-8 to 10-8. Under these conditions the electron energy distribution function is highly non-Maxwellian. As a consequence it is necessary to solve the Boltzmann transport equation based on a detailed knowledge of the electron collisional channels in order to establish the electron distribution function as a function of the ratio of the electric field to the neutral gas density, E/N, and species concentration. Development of the fundamental techniques for solution of the Boltzmann equation are presented in detail by Shkarofsky, Johnston, and Bachynski [44] and Holstein [45]. 

The effectiveness of a given plasma-assisted surface treatment depends primarily on the nature of the feed gas, and on a number of externally controllable parameters pressure, power, gas flow rate, frequency of the electrical energy used to excite the discharge, reactor geometry, etc. These "external variables, in turn, affect the "internal" plasma parameters which control the overall processes, namely the electron density ne, the average electron energy , the electron energy distribution function f(E), and the plasma potential... 

For both processes mentioned above, the bulk plasma characteristics (electron energy distribution function and plasma potential) are varied. It is thus difficult to distinguish whether the resulting film microstructure is controlled by processes in the plasma volume (for example different fragmentation of the monomer molecules) or by surface effects. 

In this relation Q(V) is the cross section for the reaction as effected by electrons of energy V and is zero for V < 7, the critical energy f(V) is the electron energy distribution function, and A is a numerical factor equal to 1.87 X 10 when V is expressed in electron volts and when Q(V) is in units of Tra. ... 

The electron temperature (Tg), electron density (ng) and electron energy distribution function for a plasma sustained in an argon/benzene mixture were measured by double and triple plasma-probe methods. Each probe was heated up to 1000 K with a sheathed heater, which was inserted into the probe, in order to prevent... 

In the case of a non chemical-reaction plasma, the state of the plasma can be described by the electron energy distribution function, f(e) (J ). In the case of a polymerizing plasma, however, f(e) may not be sufficient. In other words, the structure of the... 

Figure 6. Electron energy distribution function in a plasma generated under Condition A (see Table 1). Maxwell and Druyvesteyn distributions were calculated under the assumption that the total energy and the total electron density were the same as those observed.

Figure 7. Electron energy distribution function of a plasma under Condition B...

Figure 9. Electron energy distribution function of an argon plasma under the condition of 0.5 torr, 40 W, 500 STP mL/min...

In the original treatment of Gurney/ the current was expressed as the integral of the product of electrolyte and electron energy distribution functions but with the electronic one written as a Boltzmann factor, exp( A /fcT). The symmetry factor was introduced intuitively in terms of the shift of intersection point of energy profiles in relation to change of electrode potential, i.e., of the Fermi-level energy (cf. Butler ). 

Electron energy distribution functions have been calculated by different authors2, 3 34-36> 68-70) jjy solving the appropriate Boltzmann equation. 

Fig. 1. Electron energy distribution functions f (u) as a function of energy at different E/N values (--- cold molecular...

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