Observation of high density recording states using magnetic fine particles made by sputtering method

High density recording patterns were visualized by sputter-deposition of magnetic fine particles on recording media. Very clear patterns were formed when the magnetic particles were deposited under a weak magnetic field onto the sample surface covered with a thin oil layer. By using this process, the recorded patterns at a density of 100 k FCI (bit length 0.25 μm) were very clearly observed by a scanning electron microscope. This method gives very effective measures to investigate the recording states of magnetic and magneto-optical media.