Ion-Induced Deposition

Federici, C.H. Skinner, J.N. Brooks, J.P. Coad, C. Grisolia, A.A. Haasz, A. Hassanein, V. Philipps, C.S. Pitcher, J. Roth, W.R. Wampler, D.G. Whyte Plasma-material interactions in current tokamaks and their implications for next step fusion reactors. Nucl. Fusion 41, 1967 (2001) 

Phillips, P. Wienhold, H.G. Esser, J. von Seggern, M. Rubel Hydrogen inventories in nuclear fusion devices. J. Nucl. Mater. 290-293, 381 (2001) 

Krieger, R. Neu, J. Perchermaier, and ASDEX Upgrade Team. Carbon layers in the divertor of ASDEX Upgrade. J. Nucl. Mater 290-293, 317 (2001) 

and the ASDEX Upgrade Team On the formation of a-C D layers and parasitic plasmas underneath the roof baffle of the ASDEX Upgrade divertor. J. Nucl. Mater 313-316, 337 (2003) 

and the ASDEX Upgrade Team Characterisation and formation of a-C D layers below the divertor of ASDEX Upgrade. Physica Scripta T103, 25 (2003) 

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Figure 5. Co dots (800 nm diameter) fabricated by IBICVD technology the principle of ion-induced deposition (left) and FIB in-situ imaging (right).

Another set of experiments was carried out in an IJHV-based system working with well-defined, quantified particle beams. This system was employed to measure the sticking coefficient of methyl radicals (CH3), the simultaneous interaction of CH3 radicals and atomic hydrogen or low energy ions leading to chemical sputtering and ion-induced deposition, respectively, and the simultaneous interaction of all tree species (CH3, H, and ions). 

In summary, the importance of ion-induced secondary-electron emission in plasma environments is demonstrated by, among other things, the fact that it produces a substantial fraction of the ions, generates significant heating of surrounding surfaces, and modifies the properties of deposited films. 

A correlation between the total momentum of impinging ions per deposited boron atom and the c-BN deposition has been observed. In this model, c-BN formation is correlated with the momentum-drive process, such as the formation of point defects in conjunction with the stress-induced phase transformation. 

The stress in c-BN layers caused by the high energetic ions is a problem, because many of the nano-cBN coatings delaminate during or immediately after deposition. Several investigations have showed ways to reduce the stress in the layers (e.g. buffer layers [205, 217, 236], regulation of the ion energy [207], or ion-induced stress relaxation [206]). 

Recent interest in ion beam processing has focused on studies of ion implantation, ion beam mixing, ion-induced phase transformations, and ion beam deposition. These interests have been stimulated by the possibilities of synthesizing novel materials with potential applications in the semiconductor, tribological, corrosion, and optical fields. 

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