Superparamagnetic magnetic force microscopy tips

Abstract

We report on magnetic force microscopy (MFM) images of a thin-film magnetic recording head taken using batch micromachined silicon tips coated with nanocomposite Fe60(SiO2)40 and Fe70(SiO2)30 films. The small Fe grain size (<10 nm) and dilute Fe volume fraction (0.29-0.4) of these granular films produce tip coatings of low remanence and essentially zero coercivity, reduced ; by the superparamagnetic properties of these films. We have used these tips to obtain MFM images of the write field of the head with high spatial and magnetic-field resolution. In comparison to images taken using commercial Co85Cr15-coated tips, these MFM images show reduced tip memory effects and clearly delineate the gap field from the pole pieces. © 1996 American Institute of Physics.