Patent ID: 6940701
Filing Date: 2005-09-06
Classification: B82Y,G01D,G01R,H01F,Y10T

Abstract:
1. A production process of a magnetic sensor comprising, on a substrate, a pinned layer, a free layer and a bias magnet film being a permanent magnet that applies a bias magnetic field to the free layer to form a magnetoresistive effect element having a resistance value varying according to a relative angle made by a direction of magnetization in the pinned layer and a direction of magnetization in the free layer, comprising: a step of preparing a magnet array configured such that plural permanent magnets are arranged on a lattice point of a tetragonal lattice and a polarity of a magnet pole of each permanent magnet is different from a polarity of the other adjacent magnet pole spaced by the shortest route; a step of manufacturing a wafer, including the substrates, on which plural island-like element films are interspersed, each element film including a film that becomes the pinned layer, a film that becomes the free layer and a film that becomes the bias magnet film; and a step of disposing the wafer in the vicinity of the magnet array so as to establish a predetermined relative positional relationship between the wafer and the magnet array, whereby the film that becomes the bias magnet film of the plural element films is magnetized by utilizing a magnetic field formed between one magnet pole of the magnet poles of the magnet array and other magnet pole, of the magnet poles of the magnet array, that is adjacent to the one magnet pole spaced by the shortest route.