Abstract: A method for testing a composite type magnetic head having a MR element and an inductive element includes a current application step of applying a current to the inductive element, with applying no external magnetic field to the magnetic head, and a measurement step of measuring output characteristics of the MR element after the current application step is finished.

Abstract: A magnetoresisive device comprises an MR element, bias field applying layers located adjacent to the side portions of the MR element, and two electrode layers that feed a sense current to the MR element. The electrode layers overlap one of the surfaces of the MR element. The total overlap amount of the two electrode layers is smaller than 0.3 &mgr;m. The MR element is a spin-valve GMR element. The MR element incorporates a base layer, a free layer, a spacer layer, a pinned layer, an antiferromagnetic layer, and a cap layer that are stacked in this order. The pinned layer includes a nonmagnetic spacer layer, and two ferromagnetic layers that sandwich this spacer layer.

Abstract: A magnetoresisive device comprises an MR element, bias field applying layers located adjacent to the side portions of the MR element, and two electrode layers that feed a sense current to the MR element. The electrode layers overlap one of the surfaces of the MR element. The total overlap amount of the two electrode layers is smaller than 0.3 &mgr;m. The MR element is a spin-valve GMR element. The MR element incorporates a base layer, a free layer, a spacer layer, a pinned layer, an antiferromagnetic layer, and a cap layer that are stacked in this order. The pinned layer includes a nonmagnetic spacer layer, and two ferromagnetic layers that sandwich this spacer layer.

Abstract: A current which will change an initial magnetization state of a shield layer for a MR element is applied to an inductive element, and output characteristics of the MR element is measured.

Abstract: A method of controlling magnetic characteristics of a MR element and a method of controlling magnetic characteristics of a magnetic head with the MR element utilizing exchange coupling magnetization, include a step of supplying discrete rectangular waveform currents or a rectangular waveform current to the MR element so as to generate magnetic field in a desired direction and to generate joule heat, the generated magnetic field and the generated joule heat being applied to the MR element, and a step of controlling a duty ratio of the discrete rectangular waveform currents or a time constant of the falling of the rectangular waveform current so that a temperature of the MR element is controlled under a desired temperature change characteristics, whereby a magnetization direction caused by the exchange coupling in the MR element is aligned to a desired direction.

Abstract: A magnetic head with a spin valve effect MR element and a method of manufacturing the head. A plurality of spin valve effect MR elements on a substrate are formed, a plurality of pairs of lead conductors connected with the respective spin valve effect MR elements on the substrate are formed, and then a plurality of protection circuits of magnetization inversion connected between the respective pairs of lead conductors on the substrate are formed. Each of the protection circuits is constituted so as to turn on when it receives an energy with a level at which the pinned direction inversion in each of the spin valve effect MR elements occurs.

Abstract: A method of testing a magnetic head with a spin-valve MR element which includes at least a pinned layer, a free layer and a non-magnetic layer for magnetically separating the pinned layer and the free layer. The method includes a step of measuring an output voltage of the spin-valve MR element under application of an external alternating magnetic field to the magnetic head in a direction parallel to a magnetization direction of the pinned layer, a step of obtaining a .rho.-H loop characteristics of the spin-valve MR element from the measured output voltage, and a step of judging pinned direction of the spin-valve MR element in accordance with a polarity of an inclination of the obtained .rho.-H loop characteristics.