The goal of the project is to fabricate ultra sensitive cantilevers for magnetic resonance force microscopy. Such devices have been produced using SOI wafers and a novel fabrication process combining Al encapsulation and HF-vapor release. The realized cantilevers are 200, 350 or 500 µm long, 10 or 20 µm wide and 500 or 340 nm thick. The characterization shows promising results in vacuum at room temperature, e.g. a cantilever annealed at 800°C (L=500um, w=10um, t=0.5um) has a resonance frequency f = 2kHz, a spring constant k = 0.0004 N/m and a quality factor Q > 100000.