We report a simple atomic force microscopy-based concept for a hard disk-li
ke data storage technology. Thermomechanical writing by heating a Si cantil
ever in contact with a spinning polycarbonate disk has already been reporte
d. Here the medium has been replaced with a thin polymer layer on a Si subs
trate, resulting in significant improvements in storage density. With this
new medium, we achieve bit sizes of 10-50 nm, leading to data densities of
500 Gbit/in.(2). We also demonstrate a novel high-speed and high-resolution
thermal readback method, which uses the same Si cantilevers that are used
in the writing process, and the capability to erase and rewrite data featur
es repeatedly. (C) 1999 American Institute of Physics. [S0003-6951(99)00109
-6].