JPS5917290A - Magnetic sensor - Google Patents

Abstract

PURPOSE:To contrive to enable to manufacture the titled device by a simple process, to improve yield, to enable to manufacture at low cost, and to enhance reliability by a method wherein a substrate formed with lead out electrodes for conduction of an electric signal is cut, and a magnetic resistance effective film is formed on the section thereof being connected to the electrodes. CONSTITUTION:Aluminum stripes 12 are formed on the substrate 11 according to evaporation using a mask, and quartz glass 13 is deposited in the stripes type the same according to sputtering using a mask in the perpendicular direction thereto. Then the block is cut to form chips. The aluminum stripes 12 at the section thereof are made as to lock out on the section being surrounded by the H-shaped section of the substrate 11 and quartz glass 13. Then after the section thereof is polished, the MR film 14 is formed at least at a part thereof according to evaporation using a mask. Although the MR film 14 is formed in the U-shape as to contain the sections of the aluminum stripes 12, the MR film may be formed on the whole of the section.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a magnetoresistive magnetic sensor, and more particularly to a magnetic sensor having an extraction electrode from a magnetoresistive member.

In conventional magnetic sensors of this type, a magnetoresistive element film (hereinafter referred to as MR film) and electrodes are deposited on a substrate, and then patterned by photo-etching to form a magnetic sensor body. This process will be explained below.

First, a 600λ MR film made of Fe-Ni alloy was placed on the substrate.
Deposits to a certain thickness. Next, add 5 M thin films that will later become electrodes.
It is deposited to a thickness of about oooA. A completed magnetic sensor is obtained by thinning both layers to form a magnetoresistive part with a line width of about 100 μm, and then selectively etching to extract an aluminum electrode that guides an electric signal from the magnetoresistive part obtained as described above. I was getting it.

However, as mentioned above, this type of conventional magnetoresistive magnetic sensor requires complicated processes such as photolithography process and 2nd process, making it difficult to reduce costs due to the large number of man-hours, and at the same time hindering the improvement of yield. There was a drawback.

The present invention has been made in view of the above-mentioned drawbacks of conventional magnetic sensors, and can be manufactured through a simple process and has a high yield.
The present invention aims to provide a highly reliable magnetic sensor that can be manufactured at low cost.

In order to achieve the above object, in the present invention, a substrate on which extraction electrodes for guiding electrical signals are formed is cut, and a magnetoresistive film is formed on the cut surface by bonding to the electrodes by a method such as mask evaporation. A configuration was adopted.

Hereinafter, the present invention will be described in detail based on embodiments shown in the drawings.

FIG. 1 and subsequent figures provide a detailed explanation of the present invention, and the same or corresponding parts in each figure are given the same reference numerals.

1 to 4 show the structure of the magnetic sensor of the present invention in the order of manufacturing steps. First, as shown in FIG. 13 is similarly deposited in stripes by mask sputtering. This quartz glass serves as a reinforcing and protective layer.

Next, for example, line AA, line λ-N and line B in FIG.
The block obtained above is cut along the -B line and the B'-B' line to form a chip as shown in FIG. As shown in the figure, the aluminum stripe 12 is surrounded by the H-shaped substrate 11 and the cross section of the quartz glass 13 at the cut surface thereof.

Next, after polishing this cut surface, an MR film f4 is formed on at least a portion thereof by mask vapor deposition as shown by diagonal lines in FIG. In the example shown in FIG. 4, the MR film 14 is formed in a U-shape to include the cross section of the aluminum stripe 12, but the shape is not limited to this, and the MR film may be formed over the entire cut surface. Of course it's good too.

In addition, as shown in FIG. 5, the cut surface is polished by stacking a plurality of chips after cutting shown in FIG. may be formed.

In the above explanation, for ease of understanding, quartz glass 13
．． Although the aluminum stripe 12 is shown in the form of a square bar, it is actually more like a round bar with rounded corners.

In the above assembly structure, after forming a large number of aluminum stripes 12 and quartz glass 13 on a substrate 11, it is possible to cut them to form a large number of individual chips, resulting in high yield, easy manufacturing, and low cost. There are advantages to being able to down.

In addition, if the above structure is adopted, the MR film can be formed in the final process, so there is no need to etch the KMR film as in the past, and there is no need to select a material for the MR film that is designed to be etched. The material of the film can be selected completely freely, and the MR film is not damaged by etching residue, so a magnetic sensor with good characteristics can be obtained.

Furthermore, in the past, after cutting the element chips, it was necessary to polish the surface on which the MR film would be formed for each chip, but with the structure according to the present invention, the polishing method shown in FIG. 5 is possible. Productivity can be significantly improved.

As is clear from the above description, according to the present invention, a substrate on which an extraction electrode for guiding an electric signal is formed is cut,
The structure is such that a magnetoresistive film is bonded to the electrode on this cut surface by a method such as mask vapor deposition, so the structure is simple, the production yield is high, and the structure is simple and inexpensive. A magnetic sensor can be provided.

[Brief explanation of the drawing]

The figures are for explaining the present invention. Figures 1 to 4 are perspective views explaining the assembly structure of the magnetic sensor of the present invention, and Figure 5 is the formation of the magnetoresistive film of the magnetic sensor of the present invention. It is an explanatory diagram showing an example of a law.

Claims (1)

[Claims] A magnetic sensor characterized in that a substrate on which an extraction electrode for guiding an electric signal is formed is cut, and a magnetoresistive element film is formed on the cut surface by bonding to the electrode by mask vapor deposition or the like.