Magnetic imaging of ferromagnetic domains by room temperature scanning hall probe microscopy using GaAs/AlGaAs and bismuth micro-hall probes

Sandhu A., Masuda H., ORAL A., Bending S., Inushima T.

Physics of Semiconductor Devices, Delhi, India, 11 - 15 December 2001, vol.4746 II, pp.950-955 identifier

  • Publication Type: Conference Paper / Full Text
  • Volume: 4746 II
  • City: Delhi
  • Country: India
  • Page Numbers: pp.950-955
  • Middle East Technical University Affiliated: No


Heterostructure GaAs/AlGaAs and bismuth (Bi) micro-Hall probes were integrated into a room temperature scanning Hall probe microscope system (RT-SHPM) for imaging localized magnetic fluctuations at the surfaces of floppy disks, crystalline garnet thin films, and strontium ferrite permanent magnets. At a drive current of 800 μA the sensitivity of the Bi micro-probes was 0.38 G/√ Hz and comparable with the GaAs/AlGaAs probes. Bi nano-Hall probes with an active region of 200 nm × 200 nm were fabricated by focused ion beam milling and successfully used for magnetic imaging of ferromagnetic domains structures. Bismuth was found to be a practical alternative to semiconductors for fabricating ultra-high resolution nanometer scale Hall probes.