Magnetic reversal of sub-100 nm nanostructures studied by a FIB-trimmed recording head

Abstract

Arrays of sub-100 nm square islands have been fabricated by patterning perpendicular Co 70 Cr 18 Pt 12 continuous films using focused ion beam (FIB) lithography. The recording studies were performed on a quasistatic write/read tester using FIB trimmed recording heads with a write width of about 100 nm. We demonstrate the ability to write controlled magnetic patterns by addressing individual single-domain islands in dense island arrays achieving bit densities as high as 60 Gbit/in 2 and to read back the written information. The range of write current over which single islands can be written is modeled using a write model which includes the write field distribution and the island switching field distribution. A window is found over which individual islands can be addressed without switching nearest neighbors.

Magnetic Films on Nanoparticle Arrays

“…Writing imposes a careful lateral adjustment of the recording head position on the track and requires the synchronization of write pulse to the media pattern [69][70][71]. For this probe recording scheme, a scanning tunneling microscopy or an atomic force microscopy cantilever tip coated with a magnetic material used to read/write information to each magnetic nanostructure is considered to be promising [72].…”