AVS 50th International Symposium
    Magnetic Interfaces and Nanostructures Tuesday Sessions
       Session MI+NS-TuA

Paper MI+NS-TuA6
Submicron Cobalt Particle Fabrication by Ion Beam Induced Chemical Vapor Deposition (IBICVD)

Tuesday, November 4, 2003, 3:40 pm, Room 316

Session: Self Assembly and Nanomagnetism
Presenter: Y. Kageyama, Toyota Technological Institute, Japan
Authors: Y. Kageyama, Toyota Technological Institute, Japan
T. Suzuki, Toyota Technological Institute, Japan
Correspondent: Click to Email
Nanometer-sized patterned structures for high density data storage have recently become of great interest. It has been demonstrated that the ion-beam induced chemical vapor deposition (IBICVD) technique has a potential benefit for fabrication of nano-dots.@footnote 1,2@ Characterization of IBICVD-synthesized Co particles was performed, and the result is presented in this paper. The submicron Co particles were deposited on Si@sub 3@N@sub 4@ substrates by a focused Ga@super +@ ion beam (FIB) system equipped with a source reservoir filled with precursor of octacarbonyl dicobalt [Co@sub 2@(CO)@sub 8@] powders. Vapor of the precursor was introduced though a feeding nozzle (0.5mm diameter) above the substrate separated by 0.5 mm. The base pressure of the deposition chamber was about 10@super -5@ Pa. The ion current and the pressure during deposition were 14 pA and 0.7 - 1.4 x 10@super -4@ Pa, respectively. The in-situ image of Co particles was taken by SEM of the FIB system. Under the condition of irradiation of ion beams, the particle formation process is rather complicated due to concurrence of competitive processes (etching and deposition), therefore the morphology of Co particles strongly depends on the ion beam dwell time (5 to 120 µms) and the partial pressure of Co@sub 2@(CO)@sub 8@ precursor, as revealed by AFM analysis. The smallest size of Co particle obtained is about 150 nm so far. They exhibit ferromagnetic behaviors. Further studies on modification of properties by heating substrates, and on formation of alloys by introducing a second deposition source, are in progress. @FootnoteText@@footnote 1@ A. Lapicki, E. Ahmad, and T. Suzuki, J. Magn. Magn. Mat. 240 (2002) 47@footnote 2@ A. Lapicki, K. Kang, and T. Suzuki, IEEE Trans. Magns. 38 (2002) 2589.