Magnetic force microscopy study of submicron track width recording in thin-film media

Abstract

The magnetic force microscopy (MFM) technique is used to investigate the writing properties of a set of thin-film heads with track widths ranging from 2 to 0.5 μm. MFM images show that track edge percolation occurs at lower densities than on-track intertransition percolation. Track edge percolation results in track edge fluctuations and effective track width reduction. As the head track width is reduced to the near-micron or submicron ranges, the track edges become dominant portions of the track and consequently cause severe degradation of the recording tracks. Track edge percolation is caused by a poor edge field gradient and is possibly enhanced by pole tip corner saturation. In order to achieve high-density narrow track recording, high moment writing heads become necessary.