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Summary form only given. Co/sub 70/Cr/sub 18/Pt/sub 12/ perpendicular media has been patterned using a focussed beam of Ga/sup +/ ions (FIB) into arrays of sub -100nm islands suitable for demonstrating high density recording. The islands show single domain behaviour below a critical size, which in this case is approximately 110nm. In order to characterise the change to the magnetic properties introduced by FIB patterning, we have measured reversal properties including switching field distributions and thermal decay rates by magnetic force microscopy (MFM) imaging and Kerr rotation. The MFM was used to measure small arrays of islands by counting reversed islands at remanence as a function of reverse field or decay time. The Kerr measurements were averaged over larger arrays using a /spl sim/20/spl mu/m focussed laser beam. As a comparison unpatterned media was measured both using Kerr rotation and vibrating sample magnetometer (VSM).

Summary form only given. Patterning magnetic media with pre-defined, single-domain magnetic bits is one possible candidate for extending magnetic storage densities beyond the limit set by thermal decay for continuous media. In order to study the writing and read-back characteristics of high density patterned media, prototype nanometer-scale magnetic structures were made by patterning Co/sub 70/Cr/sub 18/Pt/sub 12/ perpendicular medium using a focused ion beam (FIB) of Ga/sup +/. The islands have lateral size of 80 nm and have a 103 nm along track period. For comparison, we have also used the FIB to prepare isolated narrow strips of continuous media. The recording properties of the patterned and unpatterned media were evaluated using a static write/read tester.

Summary form only given. A patterned storage media featuring independent single magnetic domain bit cells would allow one to further postpone the limitation of superparamagnetism. Ion irradiation allows the modification of the magnetic properties of Co/Pt multilayers and patterning of magnetic properties can be achieved by irradiation through contact stencil masks. Ion projection printing facilitates a resistless structuring which is attractive as a potential manufacturing process for future magnetic storage media. Complex patterns (e.g. in rotational symmetry) in the stencil mask can be transferred into the magnetic medium at a given demagnification factor (4 - 10 times) which reduces the requirements for the stencil mask process. Co/Pt multilayer media with perpendicular anisotropy grown on Si substrates as well as 1" glass disks have been used. The feasibility of ion projection printing for full disk surface processing was investigated using the process development projector in Vienna. Concentric tracks including data patterns as well as head positioning servo informations was patterned onto a 1" glass disk substrate as used in the IBM microdrive/spl trade/.