Megnetoelectric changing element and its producing method

Abstract

To obtain a magnetic sensor unit in which the deviations or the inclinations of magnetic resistance elements and a permanent magnet are low and which has substantially equivalent electric resistance values of magnetic resistance elements, by imparting equivalent magnetic fields to both of a pair of two magnetic resistance elements; and to intend to reduce the changing amount of a mid-point voltage due ot a temperature change. Many magnetic resistance elements are formed on an unmagnetized permanent magnet material, and are cut together with the permanent magnet material accurately by a dicing machine or the like. The magnetic resistance elements divided into a plurality are individually taken out, and the permanent magnet material is magnetized to a permanent magnet. The center of the magnetized permanent magnet material substantially coincides with that of the pair of two magnetic resistance elements, and equivalent magnetic fluxes can be imparted to both of the pair of two magnetic resistance elements.

Description

technical field [0001] The invention relates to a magnetoelectric conversion element whose resistance value changes with the change of the magnetic field and its manufacturing method, in particular to a magnetoelectric conversion element capable of identifying the authenticity of the item through the change of the magnetic field of the item and its manufacturing method. Background technique [0002] At present, it is well known to use a magnetoelectric conversion element (also called a magnetosensitive sensor) composed of a magnetosensitive element such as indium antimonide material InSb (abbreviated as InSb) to detect the magnetism of a paper leaf-shaped medium. Magnetic sensor is a sensor made of semiconductor InSb crystal (hereinafter referred to as MR chip) which is sensitive to magnetic field. It can change the resistance value of MR chip with the change of magnetic field, and detect the change of magnetic field or the presence or absence of magnetic substance. Output i...

AI Technical Summary

Problems solved by technology

[0007] In fact, it is not easy to obtain the same magnetic flux for the magnetic sensitive elements 11 and 12 by adopting the above various methods, and it is also very difficult to obtain a magnetoelectric conversion element with almost the same resistance value. of

In addition, because there are many adhesive layers between the magnetic sensitive elements 11 and 12 and the permanent magnet 21, and the number of bonding processes in the manufacture is increased, the problem of the inclination 91 is likely to occur.

[0008] Simultaneously, there are not only a slight offset 71, a slight inclination 81, a slight non-parallel 91, etc. between the magneto-electric conversion element formed by two pairs of magneto-sensitive elements 11 and 12 together with the substrate 31 and the permanent magnet 21, which will cause two The impedance values ​​of the paired magnetic sensitive elements 11 and 12 are different, and the change with the ambient temperature will also cause the rate of change of the impedance values ​​of the pair of magnetic sensitive elements 11 and 12 to be inconsistent, such as Figure 10 shown

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