The paper describes the application of Fe-based nanocrystalline ribbon to a
common-mode noise filter in the 1 MHz similar to 1 GHz frequency range. A
10 mu m thick Fe-based amorphous ribbon was converted into an Fe-based nano
crystalline ribbon by annealing it at 550 degrees C for 10 min. The ribbon
exhibited high permeability and high impedance characteristics when it was
annealed in a transverse magnetic field. The resistance of a 5 mm diameter
roll of Fe-nanocrystalline ribbon (12.5 mm wide and 6 cm long) increased fr
om 3 Omega at 1 MHz to 10 Omega at 1 GHz. We confirmed that this filter exh
ibited the same noise attenuation as a conventional filter (ferrite core) h
ut with 1/33rd its volume.