Electron energy distribution

Figure C2.13.2. Electron energy distributions/(U) for a mean electron energy of 4.2 eV, Maxwell distribution (M), Dmyvesteyn distribution (D) and a calculated distribution (Ar) for an Ar plasma [12].

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 5.2 The modification of the electron energy distribution curve by the presence of diffraction limits in a crystal. The lower filled band is separated from upper unoccupied states in a semiconductor by a small energy difference, so that some electrons can be promoted to conduction by an increase in temperature...

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-... 

A critical point in the retrieving of the number of nuclear reactions in laser-solid experiments is that there is no control on the spectrum of the electrons accelerated in the interaction, as well as the acceleration mechanism is uncertain and difficult to fit in a predictable scheme. In most cases, the electron energy distribution is assumed to be Boltzmann-like and deconvolutions are performed starting from this assumption. 

For low density electron ensembles such as electrons in semiconductors, where electrons are usually allowed to occupy energy bands much higher and much lower than the Fermi level, the probability density of electron energy distribution may be approximated by the Boltzmann fimction of Eqn. 1-3, as shown in Fig. 1-3. The total concentration, n.,of electrons that occupy the allowed electron... 

Fig. 1-3. Probability density of electron energy distribution, fli), state density, D(t), and occupied electron density. Die) fit), in an allowed energy band much higher than the Fermi level in solid semiconductors, where the Boltzmann function is applicable.

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...

Figure 7. Representation of the parameter problem in plasma processes. The symbols n, /(e), TV, and r are electron density, electron energy distribution, gas density, and residence time for molecules in the plasma volume, respectively. (Reproduced with permission from Ref. 32.)...

In other words, emission intensity is a very intimate convolution of the electron energy distribution (A >/( )), electron density (n ), and the density (np) of the species whose concentration is being monitored. 

Shape descriptor derived from the second derivative of the electronic energy distribution with 2 meaning the shorter length rays are represented and 4 meaning that intermediate property values are represented. 

Fig. 3.8 Electron energy distribution at the contact between a semiconductor and a redox electrolyte for two different redox systems at equilibrium, (a) n-type semiconductor, and (b) p-type semiconductor.

Fig. 2.1. Representation of the parameter problem in plasma-surface interaction. n,-electron density, f(E)-electron energy distribution, N-gas density, x-residence time for gas molecules in plasma volume...

Multiplication of P by the number of electrons arriving at unit surface in unit time should then give the field emission current density J. The argument just presented has limited itself to electrons at the top of the Fermi sea. It is apparent from Equation (1) and the nature of the electron energy distribution that this assumption is good. 

The potential curve diagram is especially instructive for the discussion of electron-energy distributions P(e) and of the corresponding distributions of relative kinetic energy after Pgl, P(Ek(e)), which is connected to P(e) by the relation... 

In (11.20) contributions from transitions occurring at distances determined by (II. 1) are summed. The total electron energy distribution is obtained by summing over / or integrating over impact parameter b. 

Starting from the expression for the electron energy distribution a(e) [equation (11.43)], simple semiclassical relations can be derived under special conditions regarding the potentials K(7 ) and K+(f ).17,25 This is done by replacing in the integral in (11.43) the wave functions by WKB-wavef unctions... 

The unusual complex potential derived for He(2 S)-Ar does not lead to contradictions with other experimental data, such as total ionization cross section and electron energy distribution, but rather explains some of the observed differences between the systems He(2l5 ) Ar and He(235) Ar. 

Spontaneous Ionization in Slow Collisions 3. Electron Energy Distributions... 

Figure 12. Penning electron energy distributions for systems with weak attraction between metastables and target.

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