Magnetic nanodot arrays produced by direct laser interference lithography

Periodic magnetic nanodot arrays have been produced on an area as large as 1 cmx1 cm by direct nanolithography using interferometric laser radiation. The dots are formed by the local annealing of sputtered amorphous Co-C film s in regions where the laser intensity is highest. At room temperature the dots exhibit ferromagnetic order and are embedded in a paramagnetic matrix. The onset of room-temperature ferromagnetism is caused by nanoscale chemic al and morphological changes during dot formation and reflects the phase se paration of magnetic Co-rich clusters. The present single-step nanolithogra phy is potentially an efficient method for fabrication of patterned magneti c arrays. (C) 2001 American Institute of Physics.