Microcantilever torque magnetometry of thin magnetic films

We have developed a microcantilever torque magnetometer based on a torsion- mode atomic force microscope. Thin magnetic films are deposited directly on to micromachined silicon cantilevers. We have measured hysteresis loops of iron thin films with thicknesses ranging from 1 to 40 nm and total magnetic volumes ranging from 2.2x10(-11) to 8.8x10(-10) cm(3). The magnetic moment sensitivity is estimated to be 1.3x10(-12) A m(2)/Hz(1/2) at room temperat ure and ambient conditions. We expect that by operating at the cantilever t orsion resonance frequency and at higher torque fields sensitivity will be improved by a factor of 100-1000. [S0021- 8979(00)17508-5].