Patent ID: 7082673

Claim:
A method of manufacturing a magnetoresistive device comprising: a magnetoresistive element having two surfaces that face toward opposite directions and two side portions that face toward opposite directions, and incorporating a plurality of layers including a conductive protection layer located uppermost; two bias field applying layers that are located adjacent to the side portions of the magnetoresistive element and apply a bias magnetic field to the magnetoresistive element; and two electrode layers that feed a current used for magnetic signal detection to the magnetoresistive element, each of the electrode layers being adjacent to one of surfaces of each of the bias field applying layers and overlapping one of the surfaces of the magnetoresistive element; the method comprising the steps of: forming the magnetoresistive element; forming the two bias field applying layers; forming two nonconductive layers in two regions that include ends of the magnetoresistive element near the side portions thereof and that are parts of the one of the surfaces of the magnetoresistive element; and forming the two electrode layers such that each of the electrode layers has an area greater than that of each of the nonconductive layers and is located in the one of the surfaces of the magnetoresistive element, wherein: the step of forming the magnetoresistive element includes the step of forming an oxide layer by oxidizing part of a top surface of the protection layer, in the step of forming the bias field applying layers, the bias field applying layers are formed such that parts thereof are laid over the oxide layer, and in the step of forming the nonconductive layers, the oxide layer is removed by etching except for portions thereof to be the nonconductive layers, the portions remaining because of the parts of the bias field applying layers laid over the oxide layer.