AVS 51st International Symposium
    Surface Science Monday Sessions
       Session SS-MoP

Paper SS-MoP24
Experimental Study of Cluster Size Effects on Damage Formation by Size-selected Gas Cluster Ion Beams

Monday, November 15, 2004, 5:00 pm, Room Exhibit Hall B

Session: Poster Session
Presenter: N. Toyoda, University of Hyogo, Japan
Authors: N. Toyoda, University of Hyogo, Japan
I. Yamada, University of Hyogo, Japan
Correspondent: Click to Email
A size-selected gas cluster ion beam (GCIB) system has been developed to study the size effects of energetic large cluster ion bombardments on a solid surface for the first time. This system equipped a permanent magnet with a magnetic flux density of 1.2 T. There is a sliding detector and sample holder on a guiding rail perpendicular to the incoming cluster beam axis. By locating a sample at a certain position, particular size of cluster ion can be irradiated continuously with affordable ion current density. With this magnetic filter, the cluster size distribution became 1/20 of those obtained in the conventional GCIB systems. Cluster size effects on damage formations in Si substrates were studied with the size-selected cluster ion beams. When the total acceleration energy of Ar-GCIB was 5keV, both amorphous and oxide thickness on Si substrate increased with decreasing cluster size. In the case of cluster size above 10,000, the irradiation damage in Si was dramatically reduced. This result showed good agreement with that obtained from molecular dynamics simulations. It indicated that very low-damage surface processing can be possible by controlling both the acceleration energy and the cluster size.