Ion-assisted etching

Figure C2.18.3. Relationship between ion-assisted etching and directionality in plasma etching, (a) Demonstration of the synergy between ion bombardment and reactive species during ion-assisted etching, (b) Ions incident on an etched feature. This situation prevails in glow discharges when the feature dimensions are much less than the plasma sheath thickness. Reproduced from [35]...

The talk will briefly review some of these developments ranging from high temperature equilibrium plasmas to cool plasmas, PECVD, ion implantation, ion beam mixing and ion assisted etching and deposition. Brief consideration will also be given to sputtering and ionised cluster beam deposition techniques in inorganic synthesis. 

We now direct our attention toward the understanding of possible mechanisms which produce ion-assisted etching. Whereas the thrust of this section is directed toward etching reactions, it should be emphasized that many of the concepts are also applicable to chemical reactions which produce involtaile products. 

Fig. 27. The SiF pressure as a silicon surface is rotation into a beam of XeFj molecules with an without Ar ion bombardment. The SiF pressure was determined mass spectrometrically. The ratios of the pressure increases (top curve to bottom curve) indicate the magnitude of ion-assisted etching. The experiments were performed in a standard UHV system of the type often used for surface experiments. The experimental arrangement was similar to that described in Ref. )...

Reaction conditions which influence the fluorination of LDPE in the fluorine plasma have also been discussed previously ( ) High pressures and flow rates favored the fluorination reaction kinetics. There was a competition between ion-assisted etching... 

B. Molecular Dynamics Studies of Ion-Assisted Etching Mechanisms... 

Sanders F H M, Kolfschoten AW, Dieleman J, Haring R A, Haring Aand deVriesA E 1984 Ion-assisted etching of silicon by molecular chlorine J. Vac. Sol. Technol. A 2 487-91... 

Levinson J A, Shaqfeh E S G, Balooch M and Hamza A V 1997 Ion-assisted etching and profile development of silicon in molecular chlorine J. Vac. Sci. Technol. A 14 1902-12... 

In addition to the chemical etching described above, there are other kinds of etching processes, namely physical etching and ion-assisted etching. 

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