  We present a new method for torque magnetometry by using a commercially
available membrane-type surface-stress sensor (MSS). This sensor has a silicon
membrane supported by four beams in which piezoresistive paths are integrated.
Although originally developed as a gas sensor, it can be used for torque
measurement by modifying its on-chip wiring. We demonstrate the magnetic-torque
measurement of submillimeter-sized crystals at a low temperature and in strong
magnetic fields. This MSS can observe de-Haas-van-Alphen oscillation, which
confirms that it can be an alternative tool for self-sensitive
microcantilevers.
