Magnetic Force Microscopy — Towards Higher Resolution

Abstract

In this chapter, magnetic force microscopy is treated in detail with an emphasis on high resolution and hard magnetic materials such as recording media. The chapter starts with basic MFM operation, instrumentation, and a frequency domain theory of image formation using transfer functions. Subsequently, the limits of resolution in MFM are discussed, and the concept of criticalwavelength as ameasure for resolution is introduced. To achieve high resolution, the tip-sample distance has to be small, and methods of tip-sample distance control are discussed. Finally, generations of MFM tips are treated, including a full silicon micromachined design, which eventually might take the resolution of MFM below 10 nm.1