Recent Advances in Magnetic Force Microscopy

M. R. Koblischka and U. Hartmann

Institute of Experimental Physics, University of Saarbrueken, Germany

Microstructured thin film elements with critical dimensions of 1 ｵm or below play an in-creasingly important role in magnetic components for information technology applications. Examples which are directly based on such microstructures are key components in magnetoe-lectronics for storage and sensor applications as well as modern concepts which are likely to substitute today's hard disk drives. Basic research on magnetic materials as well as the men-tioned industrial applications create an increasing demand for high-resolution magnetic imaging methods. During the past ten years magnetic force microscopy (MFM) has become probably the most powerful general-purpose method for magnetic imaging. MFM can be applied under various environmental conditions and requires only little sample preparation. On the other hand, a resolution of about 100 nm can be achieved in a routine way.

In spite of the considerable achievements MFM also involves some serious shortcomings which could not have been overcome so far: In the general situation the method yields only qualitative information about the magnetic object and it is difficult to improve the resolution to values below 100 nm.

The present contribution will report on some new concepts which have been realized in the field of advanced probe preparation, based on electron beam methods. The advanced probes allow high-resolution imaging of magnetic fine structures within thin film permalloy elements exhibiting a complicated cooperative magnetization reversal process. The investigations are of importance for various concepts underlying modern magnetic data storage developments.