HIGH-FIELD MAGNETIC FORCE MICROSCOPY

Magnetic force microscope (MFM) studies of high-density thin-film recording media have been performed in the presence of an applied magnetic field, In particular, the erasure behavior of bit transitions in the media have been investigated. For these studies a compact, high-field de magnet has been constructed that fits the laser head of a Nanoscope III multimode microscope. Because of space constraints and concern over thermal drifts which could affect the stability of the MFM, a rotating permanent magnet was used instead of an electromagnet. The magnet is mounted in a yoke which guides varying amounts of flux to the sample. This was used to observe the erasure of bits in a magnetic hard disk. The applied field also magnetized the MFM cantilever, making it possible to magnetically characterize both the sample and the probe. (C) 1995 American Institute of Physics.