Micromachined III-V cantilevers for AFM-tracking scanning Hall probe microscopy

In this paper we report the development of a new III–V cantilever-based atomic force sensor with piezoresistive detection and an integrated Hall probe for scanning Hall probe microscopy. We give detailed descriptions of the fabrication process and characterization of the new integrated sensor, which will allow the investigation of magnetic samples with no sample preparation at both room and cryogenic temperatures. We also introduce a novel piezoresistive material based on the ternary alloy n+-Al0.4Ga0.6As which allows us to achieve a cantilever deflection sensitivity ΔR/(R Δz) = 2 × 10−6 A−1 at room temperature.