Fabrication and characterization of CoZrGd Hall sensors

Thin films of the amorphous ternary alloy CoZrGd are deposited by single ta rget magnetron rf sputtering. The Hall effect was studied as a function of Gd percentage. The amorphous films show unusually large spontaneous Hall ef fect, whose sign is strongly dependent on the film composition, as explaine d by the model of McGuire et al, Also, the films display perpendicular easy axis anisotropy, which significantly reduces the field needed to obtain te chnical saturation of the spontaneous Hall effect, Thus the sensitivity of the films can be substantially increased. The highest magnetic field sensit ivity (-14.8%/Tesla) is accomplished with Hall angle (rho (H)/rho) of -2.07 % at a saturation field of 0.14 Tesla. This film has potential application in small fields.