Conducting atomic-force-microscope electrical characterization of submicron magnetic tunnel junctions

We have developed the ability to electrically characterize submicron magnetic tunnel junctions using a conducting atomic force microscope (CAFM). This technique can be applied after only a short processing route, thereby saving time and resources, and reducing the potential for damaging the junctions. The CAFM can be used to measure hysteresis loops, magnetoresistance, resistance–area product, switching astroids, current–voltage curves, and breakdown voltage of tunnel junctions. In this letter, we outline the sample requirements, detail the CAFM processing route, describe tip preparation, and report examples of data we have obtained with this technique over the last two years.