CoSi2 nanostructures by writing FIB ion beam synthesis

✍ Scribed by Ch. Akhmadaliev; L. Bischoff; B. Schmidt

• Publisher: Elsevier Science
• Year: 2006
• Tongue: English
• Weight: 366 KB
• Volume: 26
• Category: Article
• ISSN: 0928-4931
• DOI: 10.1016/j.msec.2005.09.026

✦ Synopsis

A mass separated focused ion beam (FIB) is a very useful tool to fabricate nanostructures by writing implantation within an ion beam synthesis process. In these investigations the IMSA-OrsayPhysics FIB, equipped with a Co 36 Nd 64 alloy liquid metal ion source, was applied. Si(100) and ( 111) wafers were implanted with 60 keV Co ++ ions in the dose range of 2 I 10 16 to 2 I 10 17 cm À 2 . Implantation parameters were investigated, like pixel dwell time, relaxation time (time between two cycles), dose rate as well as the pixel overlapping factor. The subsequent annealing was done in a two step process, namely 600 -C for 60 min and 1000 -C for 30 min in a N 2 ambient. The results obtained by SEM investigations in terms of continuous nanowire structures following the <110> direction and interrupted CoSi 2 pattern in the <100> direction show a clear dependence on the time scale as well as the scanning mode of the irradiation. Structure sizes as small as 10 nm are demonstrated. The formation of CoSi 2 nanostructures is explained by precipitation, Ostwald ripening and coarsening leading to a shrinking of the initial implanted profile.