Etching discharge kinetics

Discharge Kinetics in Etching Processes Ion Density and Ion Flux... 

The siuface kinetics of etching (Section 8.2.7) is controlled by concentrations of ions and active neutrals near the surface. Determination of these parameters reqttires a detailed consideration of etching discharges (Sections 8.2.8 and 8.2.9). Some nseful relations, however, can be derived from general kinetics of the low-pressme discharges applied for etching. In this section, we make such estimations for the concentration and flux of ions concentration and flux of neutral chemically active etchants will be estimated in the next section. A balance of charged particles in plasma between electrodes with area A (characteristic radius R) and narrow gap / between them (/ R), controlled by ionization and losses to the electrodes,... 

Finally, the ion flux at the etching surface, which is also required for etching surface kinetics calculations, can also be expressed as a function of the total power of the nonequilibrium low-pressure discharge (see Section 8.2.7) ... 

Discharge Kinetics in Etching Processes Density and Flux of Neutral Etchants... 

Plasma Etching of Silicon in CF4 Discharges Kinetics of Fluorine Atoms... 

The kinetics of surface recombination of F atoms can be characterized by the recombination probability per incident atom, Prec, and depends on the surface material. These probabilities, with some exceptions, are small at substrate temperatures and atontic fluxes typical for the etching discharges. Numerical values of the F-atom surface recombination coefficients are presented in Table 8-2. Surface recombination coefficients for Cl and O atoms are larger and reach values of about 0.1 for mat r surfaces. It is also important to notice that the probability of an etching reaction of one F atom per one silicon surface collision is Pr 1-7 10 and is negligible for most of other surfaces. The reaction probability, however, can be very high and even reach Pr 1 in some specific cases, for example, in F etching of a BN surface. 

Kinetics of Polymer Etching in an Oxygen Glow Discharge... 

The fundamental kinetics and transport properties of plasma processes are reviewed and applied to polysilicon etching in Cla discharges. The relative neutral flux, ion flux, and ion energy is critical in controlling the directionality of the etching process. The electron density and energy have been estimated from electrical impedance measurements of Cl2 discharges. 

---