JP2607528B2 - Method of manufacturing magnetoresistive element - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of manufacturing a magnetoresistive element for extracting the strength of a magnetic field as a change in electric resistance.

[Prior Art] A manufacturing process according to a conventional manufacturing method of a magnetoresistive element is described as a second example.
This will be described with reference to FIGS.

In the conventional manufacturing process, first, as shown in FIG. 2 (A), a substrate 1 formed from a non-magnetic material such as glass is formed into a rectangular flat plate as a substrate for forming a magnetoresistive element.

Next, a magnetic film composed of NiFe or NiCo or the like having a magnetoresistive effect is formed on the substrate 1 to a thickness of 300 to 2000 mm by a method such as vapor deposition or sputtering. As shown in FIG. 2B, a large number of predetermined patterns (hereinafter referred to as magnetic film patterns) 2 as the main body of the magnetoresistive element are formed by etching.

Next, as shown in FIG. 2 (C), an electrode portion at an end for connecting a connection terminal later on each magnetic film pattern 2 on the substrate 1
An insulating and inorganic protective film 3 made of SiO or the like is formed by mask evaporation or the like so as to cover each pattern 2 except for 2a. The film thickness is 1 to 30 μm.

Next, the substrate 1 is cut by dicing or the like for each unit of the magnetoresistive element as shown in FIG. 2 (D).

Next, as shown in FIG. 2E, the connection terminal 5 is soldered to the electrode portion 2a of the magnetic film pattern 2 by the solder 4.

Finally, a protective resin (hereinafter referred to as a protective resin) indicated by reference numeral 6 in FIG. 2 (F) is applied to the entire surface of the substrate 1 except for the connection portion of the connection terminal 5, and the entire surface is coated and covered. The magnetoresistive element is completed.

[Problems to be Solved by the Invention] In such a conventional manufacturing process, the coating of the protective resin 6 is not performed collectively on the substrate 1 before cutting in consideration of the soldering of the connection terminal 5, 1 is cut for each element, soldering of the connection terminal 5 is performed, and then, for each element.

However, if the protective resin 6 is coated for each element, much time and effort are required for the coating process, and the cost is accordingly increased.

When coating is performed for each element, as shown by reference numeral 6a in FIG. 2 (F), the protective resin 6 rises due to surface tension at the end of the element, and the protective resin 6 becomes thicker only there. It becomes too much.

On the other hand, there is a method in which the protection resin 6 is not coated on each element by a conventional method, but is collectively applied to the substrate 1 before cutting. This is a method of coating the protective resin 6 by a printing method or photolithography patterning so that the protective resin 6 does not adhere to the electrode portion 2a of the magnetic film pattern 2 in consideration of soldering of the connection terminal 5.

However, according to this method, the protective resin 6 used is limited to one that can be printed or photolithographically patterned, and the degree of freedom in selecting the protective resin 6 is limited. Further, in some cases, it is not compatible with the protective resin 6 that it has characteristics that can guarantee the reliability of the magnetoresistive element and that the above-described printing method or photolithographic patterning can be performed.

[Means for Solving the Problems] In order to solve such problems, in the method of manufacturing a magnetoresistive element according to the present invention, a plurality of predetermined patterns of a magnetic film as a main body of the magnetoresistive element are formed on a substrate. Performing soldering on the electrode portion connecting the connection terminals of the pattern after the step; covering the entire pattern forming surface of the substrate with a protective resin after the step; A step of cutting the substrate for each unit of the magnetoresistive element, and a step of removing a portion of the resin on the solder after the step and soldering a connection terminal to the electrode portion through the exposed solder. A configuration having

[Operation] According to such a configuration, the coating of the protective resin is performed at a time before the connection terminals are soldered and before the substrate is cut for each unit of the magnetoresistive element. It can be done cheaply in time. In addition, since the protective resin is collectively coated on the entire surface of the substrate before cutting, it is possible to prevent the protective resin from rising due to surface tension as in the above-described conventional example, and to reduce the resin to an appropriate thickness. Can be coated. Further, the protective resin to be used is not limited to a resin that can be subjected to a printing method or photolithographic patterning, and the degree of freedom of selection increases.

[Example] Hereinafter, an example of the present invention will be described in detail with reference to FIGS. 1 (A) to 1 (H). 1 (A) to 1 (H) illustrate the steps of manufacturing a magnetoresistive element according to an embodiment of the method of the present invention.
The same or corresponding parts as those in (F) to (F) are denoted by the same reference numerals, and the description thereof will be omitted or simply referred to. Further, a part of the steps of the present embodiment is the same as the conventional example, and the part is simply touched.

In the process of this embodiment, a large number of magnetic film patterns 2 are formed on the substrate 1 of FIG. 1A as shown in FIG. 1B in the same manner as in the conventional process. Then, as shown in FIG.
An insulating inorganic protective film 3 made of SiO or the like is formed so as to cover portions other than the electrode portion 2a.

Next, the present embodiment is different from the prior art in that the solder 7 is raised on the electrode portions 2a of the respective magnetic film patterns 2 as shown in FIG. Weld.

Next, as shown in FIG. 1 (F), a protective resin 6 is applied to the entire surface of the substrate 1 on which the magnetic film pattern 2 is formed, and the entire surface of the substrate 1 is coated. The method of applying the protective resin 6 is spinner coating, pull-up coating, spray coating, print coating, or the like.

Next, the substrate 1 is cut along a cutting line indicated by reference numeral 8 in FIG. 1 (F), and the substrate 1 is cut for each unit of the magnetoresistive element as shown in FIG. 1 (G).

Next, as shown in FIG. 1H, the portion of the protective resin 6 on the solder 7 is removed, and the connection terminal 5 is soldered to the electrode portion 2a of the magnetic film pattern 2 via the exposed solder 7. At this time, solder is added as necessary. Here, when removing the portion of the protective resin 6 above the solder 7, the portion of the solder 7 is higher than other portions on the substrate 1, and the thickness of the protective resin 6 thereon is small, so that heat, vibration, Alternatively, the coating of the protective resin 6 on the solder 7 can be easily broken or removed by using both of them, and the connection terminal 5 can be soldered. For example, heat and vibration can be applied simultaneously by ultrasonically vibrating the tip of the soldering iron.

Next, although not shown, the soldered portion of the connection terminal 5 is coated with a resin for solder protection as necessary,
The magnetoresistive element is completed.

As described above, according to the steps of the present embodiment, the coating of the protective resin 6 is performed collectively before the connection terminal 5 is soldered and before the substrate 1 is cut for each unit of the magnetoresistive element. In other words, the coating of the protective resin 6 can be performed collectively, easily, in a short time and at low cost. The manufacturing cost of the element can be reduced accordingly. Further, since the protective resin 6 is coated on the entire substrate 1 before cutting, the swelling of the protective resin 6 due to the surface tension as in the related art can be prevented, and the protective resin 6 can be covered with an appropriate thickness. The characteristics of the resistance element can be improved.

Further, according to the present embodiment, the coating of the holding resin 6 is not performed over the electrode portion 2a of the magnetic film pattern, so that the resin used for the protective resin 6 is limited to a resin that can be printed or photolithographically patterned. Not done. The degree of freedom in selecting the protective resin 6 is increased, a material having excellent characteristics can be used, and the reliability of the magnetoresistive element can be improved.

If the solder 7 and the protective resin 6 thereon are too tight in the state shown in FIG. 1 (G), the protective resin film may not be successfully destroyed or removed even by the heat or vibration of the soldering iron. To prevent this, a release agent or a release agent is applied on the solder 7 before coating the protective resin 6. This reduces the degree of adhesion between the solder 7 and the protective resin 6, so that the coating of the protective resin 6 can be easily broken and removed by heat, vibration, and the like.

[Effects of the Invention] As is clear from the above description, in the method of manufacturing a magnetoresistive element according to the present invention, a step of forming a plurality of predetermined patterns of a magnetic film as a main body of the magnetoresistive element on a substrate, and after the step, A step of welding solder to an electrode portion connecting the connection terminals of the pattern; a step of covering the entire pattern forming surface of the substrate with a protective resin after the step; and a step of attaching the substrate to the magnetoresistive element after the step. And a step of cutting the unit of the resin and removing a portion of the resin on the solder after the step, and soldering a connection terminal to the electrode portion through the exposed solder.
In particular, the step of covering the protective resin can be simplified, and the cost can be reduced. Further, the degree of freedom in selecting a protective resin is increased, and the reliability of the magnetoresistive element can be improved by using a resin having excellent characteristics. Further, the thickness of the coating of the protective resin can be appropriately set, and excellent effects such as improvement of the characteristics of the magnetoresistive element can be obtained.

[Brief description of the drawings]

1 (A) to 1 (H) are explanatory views of a manufacturing process of a magnetoresistive element according to an embodiment of the method of the present invention, and FIGS. 2 (A) to 2 (F) are explanatory views of a manufacturing process of a conventional magnetoresistive element. It is. DESCRIPTION OF SYMBOLS 1 ... Substrate 2, ... Magnetic film pattern 2a ... Electrode part, 3 ... Protective film 5 ... Connection terminal, 6 ... Protective resin 7 ... Solder

 ──────────────────────────────────────────────────の Continuing on the front page (72) Inventor Hideto Sano 1248 Shimokagemori, Chiba-shi, Saitama Prefecture Within Canon Electronics Co., Ltd. (72) Inventor Hisanori Hayashi 1248 Shimogaemori, Chichibu-shi, Saitama Within the company (72) Inventor Takeshi Osato 1248 Shimokagemori, Chichibu City, Saitama Prefecture Within Canon Electronics Co., Ltd.

Claims (1)

(57) [Claims] A step of forming a large number of predetermined patterns of a magnetic film as a main body of a magnetoresistive element on a substrate; a step of welding solder to an electrode portion connecting the connection terminals of the pattern after the step; A step of covering the whole of the pattern forming surface of the substrate with a protective resin, a step of cutting the substrate for each unit of the magnetoresistive element after the step, and a step of cutting the resin on the solder after the step. A method for manufacturing a magnetoresistive element, comprising a step of removing a portion and soldering a connection terminal to the electrode portion via exposed solder.