Reactive deposition bombardment effects

Bombardment-enhanced chemical reactions (film formation) Chemical reactions on a surface that are enhanced by bombardment by high energy atomic-sized particles. The effect is due to heating, the dissociation of adsorbed species, the production of electrons, etc. An important effect in reactive deposition, PECVD, plasma etching, and reactive ion etching. 

Non-rf plasmas require an anode and a cathode. In sputtering, the cathode is eroded by ion bombardment. In reactive sputter deposition the sputtered materials react with a gas in the ambient or with a co-deposited material to form a compound on the substrate. If the compound that is formed is electrically insulating, a portion of the material not on a substrate may cover a part of the anode. Over a period of time this will change the configuration of the plasma and the plasma properties. The covering of the anode is called the disappearing anode effect in reactive sputter deposition of dielectric materials. 

This definition does not specify the source of the depositing film material, the source of the bombarding particles, nor the environment in which the deposition takes place. The effects of energetic particle bombardment on non-reactive and reactive film growth are discussed in Sec. 10.4.3 and 10.5.3. 

The reactivity between co-deposited or adsorbed species can be increased by utilizing concurrent energetic particle bombardment by an inert species that does not enter into the reaction. Concurrent energetic inert particle bombardment during reactive film deposition has been shown to have a substantial effect on the composition, structure, and properties of compound films. In general, the bombardment ... 

Taguchi et al. [68, 69] applied this technique to model the reactive sputter deposition of thin Si02 films and the effect of Ar bombardment on the Si02 deposition process. In this particular case, it was found that simulating the deposition process by MD alone resulted in films with a much lower density that those typically obtained from experiments under similar conditions. Applying the sequential MD/MC approach, amorphous Si02 films with properties consistent with experiments were obtained. 

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