Scanning Hall probe microscopy on an atomic force microscope tip

We present a Hall magnetometer combined with a conventional atomic force microscope (AFM) tip. The Hall nanosensor AFM probe is fabricated in bismuth using direct-wire electron-beam nanolithography and silicon micromachining. The magnetometer is integrated into a conventional force microscope silicon cantilever which permits reliable control of the sensor-sample distance. The magnetic sensor is situated at the end of a sharp AFM allowing good access to the specimen and providing high resolution simultaneous topographic images. Since the sensors are defined lithograpically, the size and shape of sensors are well controlled and reproducible. We present the results of magnetic field imaging using this probe demonstrating quantitative magnetic field measurement and good spatial resolution.