JPS5884477A - Planar-hall element - Google Patents

Abstract

PURPOSE:To obtain desired magnetism sensing characteritics by applying force to the film of a ferromagnetic substance by coating an insulating substrate with the film while forming the planar-Hall element held and formed under a state that force is applied to the film. CONSTITUTION:The insulating substrate is coated with the film of an iron-nickel alloy as the ferromagnetic substance through vaccum deposition, etc. while the planar-Hall element is held and formed under the state that force is applied to the film, and the insulating substrate is obtained by coating a glass plate 1 with the film 2 of the iron-nickel alloy in approximately 0.1mum thickness through vacuum deposition. When a magnetic field is vertically applied to currents I in the surface of the film 2 under a state tha currents are flowed between terminals 3, 4, Hall voltage VH is generated between terminals 5, 6. Accordingly, it is considered that the change of the magnetism sensing characteristics through the application of force to the film of the ferromagnetic substance depends upon the degree of arrangement of magnetization in the film of the ferromagnetic substance.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a Hall element that can be used in a variety of applications to detect magnetism. The purpose is to

The magnetic sensitivity of a planar Hall element with a ferromagnetic film deposited on a rigid insulating substrate is determined by the deposition conditions, which is one of the means of depositing the film. Only detection becomes difficult. E. In a large alternating magnetic field, there was a problem in that the output was easily distorted and contained many double frequency components.

The present invention provides a planar Hall element that solves these problems, and embodiments thereof will be described below with reference to the drawings.

First, the differences between this planar Hall element and a conventional general Hall element will be explained.

Figure 1 shows the oblique angle of a conventional general Hall element. At U e+, a current ■ is passed between current terminals 3 and 4, and a magnetic field H is generated in a direction perpendicular to the wire.
If n is added, a Hall voltage VH is generated between the voltage terminals 5 and 6.

Figure 2 shows the current I and magnetic field H in a planar Hall element.
, Hall voltage v! It shows the direction of magnetic field H
The direction θ is in the plane of the current ■ and the Hall voltage VH,
In the case of this invention, θ is θ.

, 180° and 9 (10,270").

3rd item 1 is a plan view 1 of the planar Hall element of the present invention.
The insulating substrate is constructed by depositing a ferromagnetic material and an iron/nickel alloy coating by vacuum evaporation or other means on an insulating substrate, and holding these coatings in a state where force is applied. A film 2 of iron/nickel metal was deposited on the glass plate 1 to a thickness of 0.1 μm (Note: 1 μm) by vacuum deposition.
=]XIOfi).

Then, a current was passed between current terminals 3 and 4. When a magnetic field is applied perpendicularly to the current (2) in the plane of the coating 2, a Hall voltage vH is generated between the voltage terminals 5 and 6, and the relationship between the strength H of the magnetic field and the Hall voltage VB is as follows. As shown by characteristic A in Figure 4.

When force is applied to the coating 2 by slightly bending the glass plate 1, the relationship between the magnetic field strength H and the Hall voltage VH changes as shown by characteristic B, and when the force is further increased, it changes to characteristic C. Change as shown.

It is thought that the change in the magnetic sensitivity characteristics caused by the force ξ applied to the ferromagnetic film is due to the degree of alignment of the magnetization within the ferromagnetic film. In other words, the strain of the ferromagnetic film caused by force changes the magnetization, and for example, when nickel (N1) is the main component,
In a polycrystalline film of Nj Fe alloy containing 0x iron (Fe), the magnetostriction coefficient is negative and the magnetization is aligned in the direction perpendicular to the tension applied to the film, and as a result of the increased degree of alignment, the Hall voltage V
B increases, but at the same time, magnetic domain movement becomes difficult due to strain, and the magnetic field necessary for magnetizing the film increases,
This results in changes in magnetic sensitivity characteristics as shown in FIG. 1.

In addition, in conventional Hall elements, this can be clearly explained by the Lorentz force directly applied to carriers in a solid, but in the case of planar Hall elements, the carrier 4g
% electrons (this is spread throughout the solid and the atoms to which it belongs cannot be identified) and 3d electrons (this is localized in the solid,
Ball voltage is thought to be generated by the interaction of ferromagnetism, which often belongs to a specific atom, is the origin of ferromagnetism, and is influenced by the magnetic field.

Grainer e-Hall elements are also used to detect alternating fields, but in this case, the Hall voltage output shows a response with little distortion only in the small magnetic field range of H^ before a force is applied to the coating 2. On the other hand, in the case of characteristic B in which no force is applied, it is expanded to the range of the magnetic field of Ha, and in the case of characteristic C, it is further expanded to the range of the magnetic field of He.

For many alloys whose main component is nickel, which has a negative magnetostriction coefficient, the characteristics of this planar Φ Hall element vary greatly depending on whether tensile or compressive force is applied to the coating, as shown in Figure 4. The characteristics are as follows: In a planar Hall element as shown in Fig. 3, a magnetic field H is applied perpendicular to the current I within the plane of the coating 2 while a current is flowing between the current terminals 3 and 4.
This is the case when a compressive force is applied in the current direction, that is, the direction of the current terminals 3 and 4. Also, when a tensile force is applied, the characteristics change as shown in Figure 2 when the direction of the magnetic field is parallel to the current. Get it.

However, as a method of applying force to the coating 2, the glass plate j may be bent after the coating 2 is applied to the glass plate 1, which is an insulating substrate, or the glass plate l may be bent in advance when the coating 2 is applied. It may be curved against elasticity and then released from the curve after being applied.

Furthermore, although the purpose of this embodiment was to expand the range of the detected magnetic field, it is also possible to reduce the range of the detected magnetic field and increase the Hall voltage output per unit magnetic field. The characteristics can be adjusted depending on the

As explained above, the present invention provides a planar Hall element constructed by depositing a ferromagnetic film on an insulating substrate and maintaining the film under force. In addition, the magnetic sensitivity characteristics are not determined by the conditions when the coating is applied, and the insulating substrate is curved after the coating is applied, or the insulating substrate is bent in advance against elasticity before the coating is applied. By depositing and subsequently releasing the curvature, forces can be applied to the coating to obtain the desired magnetosensitive properties.

Furthermore, the Brehner-Hall element, in which a ferromagnetic film is applied to an insulating substrate, has a much simpler manufacturing process than conventional semiconductor Hall elements.

Furthermore, when the Brehner-Hall element of the present invention is used as a magnetic head, etc., the dynamic range can be widened, and it is still possible to widen the dynamic range.
Since a bias magnetic field is not required compared to the head), the configuration of the magnetic recording/reproducing device is simplified.

[Brief explanation of the drawing]

FIG. 1 is a perspective view of a conventional general Hall element, FIG. 2 is a diagram showing the directional relationship of current, magnetic field, and Hall voltage in a Brehner-Hall element, and FIG.
Plan view of Hall element, No. 4 [k+ is a regrettable diagram explaining this Brehner-Hall element. ]... Glass plate serving as an insulating substrate, 2... Ferromagnetic coating, 3, 4... Current terminal, 5, 6... Voltage terminal. H...Magnetic field strength, VH...Hall voltage, A, B. C...Characteristics, H^, HB, He...Magnetic field range. 111 figure 112 figure IEB figure w4 figure

Claims (2)

[Claims] (1) A planar e-Hall element constructed by depositing a ferromagnetic film on an insulating substrate and maintaining the film under force. (2) The planar coating of iF [Claim 1] is such that the coating can be applied with compressive force when the current and magnetic field are perpendicular to each other, and with tensile force when the current and magnetic field are parallel. Hall 2 children.