We have two electrical probe stations that allow us to measure longitudinal and transverse resistances in Hall bar devices using a lock-in technique. In the first station, DUTs are mounted on a motorized rotation stage and electrically connected using a wire bonder. The DUT can be rotated 360° in any given plane between the poles of an electromagnet producing fields up to 2.3 Teslas.
The second station uses the same measurement principles as the first one but the DUTs are contacted using microprobes and we are able to apply field along two axes simultaneously (in-plane 0.3 T and out-of-plane 0.05 T).
Setups are complemented with a constant ac/dc current source, a pulse generator (1-100 ns, -/+50V), a high voltage source (<1.1 kV), an arbitrary waveform generator, and a high speed advanced oscilloscope.
