JP2849100B2 - Magnetoelectric conversion element and method of manufacturing the same - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a magnetoelectric conversion element, and more particularly to a magnetoelectric conversion element in which the thickness of an element is reduced and the strength of a lead is improved, and a method for manufacturing the same.

[Prior Art] As a magnetoelectric conversion element, a Hall element in which a magnetically sensitive part is formed by an ion implantation method, a Hall element in which a magnetically sensitive part is formed by an epitaxial growth method, a Hall element in which a magnetically sensitive part is formed by a vapor deposition method, 2. Description of the Related Art There are generally known elements such as a magnetoresistive element using a magnetoresistive effect in which electric resistance is changed by a magnetic field, a magnetic transistor, and the like, for inputting a magnetic signal and extracting an electric signal output.

2. Description of the Related Art In recent years, magnetoelectric transducers, especially hall transducers, have been widely used in brushless motors used in video cassette recorders, cassette tape recorders, compact disc players, and the like. ing.

Conventionally, in order to reduce the thickness of the device, the thickness of the device having the configuration shown in FIG. 6 is reduced by polishing the back surface of the Hall element substrate, the thickness of the lead is reduced, and the height of the wire bonding group is optimized. Efforts are being made.

In the element shown in FIG. 6, the substrate 1 is bonded on the lead 401 via the adhesive 5. A Hall element magneto-sensitive section 2 is formed on a substrate 1.
The electrode 3 is formed thereon. The bonding wire 6 connected to the electrode 3 is connected to the leads 401 and 402. The entire device is made of epoxy resin 7 for molding.
Is sealed by.

[Problems to be Solved by the Invention] However, in the conventional method, for example, when a fragile material such as GaAs is used for the substrate 1 for a Hall element, when the back surface of the substrate 1 is polished, As a result, the yield is significantly deteriorated due to cracks or the like. Further, when the lead is thinned, the strength of the lead is reduced, and there is a problem in reliability, and it has been difficult to reduce the thickness of the element.

Therefore, an object of the present invention is to solve the above-mentioned problems, and to provide a magnetoelectric conversion element which has a good yield, high reliability, and is thin and small.

[Means for Solving the Problems] In order to achieve such an object, in the magnetoelectric conversion element according to the present invention, a magnetosensitive part is formed on a GaAs substrate, and electrodes of the magnetosensitive part are connected to leads by bonding wires. In the magneto-electric conversion element described above, a hole larger than the outer shape of the substrate is provided in the island portion of the lead, the substrate is inserted into the hole, and the back surface of the island portion and the bottom surface of the substrate are on the same plane. As described above, the island portion and the substrate are fixed only by an adhesive filling the gap between the inner side surface of the hole and the side surface of the substrate, and the substrate, the magnetically sensitive portion, the island portion, and the The bonding wire is sealed with a resin, and the bottom surface of the substrate is in direct contact with the sealing resin.

Further, the method for manufacturing a magnetoelectric conversion element according to the present invention includes the steps of:
In a magneto-electric conversion element in which a magnetically sensitive part is formed on a substrate and an electrode of the magnetically sensitive part is connected to a lead by a bonding wire, a step of providing a hole larger than the outer shape of the substrate in an island part of the lead; A step of attaching an adhesive tape to the back surface of the substrate, a step of inserting the substrate into the hole and fixing an inner surface of the hole and a side surface of the substrate with an adhesive, and a step of peeling the adhesive tape. And

According to the present invention, the substrate on which the magnetic sensing portion is formed is inserted into the hole provided in the island portion of the lead, and the hole is formed so that the back surface of the island portion and the bottom surface of the substrate are on the same plane. The inner side surface of the substrate and the side surface of the substrate are fixed by an adhesive, and the bottom surface of the substrate is in direct contact with the sealing resin, so that the device can be made thinner and smaller.

[Example] Hereinafter, an example of the present invention will be described in more detail with reference to the drawings.

In the following embodiments, a Hall element will be described as an example.

FIG. 1 is a plan view schematically showing the configuration of the Hall element of the present invention.

In FIG. 1, the substrate 1 is joined to the lead 401 via an adhesive. A Hall element magnetic sensing part 2 is formed on the substrate 1, and an electrode 3 is formed on the Hall element magnetic sensing part 2. A bonding wire 6 extends from the electrode 3 and is connected to the leads 410, 411, 412 and 413. Further, the element including the bonding wire 6 is sealed with an epoxy resin 7.

However, in the present invention, the through-hole is provided in the island portion of the lead on which the Hall element is mounted,
The cross section is as shown in FIG. 5 described later. As the shape of the through hole, a rectangular hole that matches the shape of the Hall element substrate is often used.

On a non-doped GaAs semi-insulating substrate having a diameter of 50 mm and a thickness of 300 μm, Si ⁺ was implanted at an acceleration voltage of 150 keV and a dose of 5 × 10 ¹² cm ^−2.
After performing ion implantation under the conditions described above, annealing is performed, subsequently, the Hall element magneto-sensitive portion 2 is formed by mesa etching, and then the input / output ohmic electrode 3 is formed of Au / Ni / Au. A Hall element was fabricated by forming with the structure of -Ge.

After that, dicing is performed and the substrate with a diameter of 50 mm is cut.
A number of 0.4 mm square devices were fabricated.

Next, as shown in FIG. 3, in order to manufacture a lead 430 in which an island portion into which a Hall element is inserted is formed with a hole,
The thickness shown in FIG. 2 0.5 mm, vertical 30 mm, prepared copper plate 8 of the horizontal 150 mm, size l ₃ = 1.2 mm of the island portion by punching the pitting so by using a mold in the center of the island portion It was a corner, and there was a size l ₄ = 0.6 mm square at the center of the island. A lead 430 having a thickness d ₂ = 200 μm was produced.

Next, in order to die-bond the individual element pellets obtained by dicing to the island portions of the prepared leads 430, a 50 μm-thick polytetrafluoroethylene was formed on the back surface of the leads 430 as shown in FIG. Then, die bonding was performed via the adhesive 5 so that the element pellets entered the holes formed in the island portions.

Next, after the adhesive tape 9 was peeled off, the electrode 3 was connected to the leads 430 and 431 via the bonding wire 6. Subsequently, sealing was performed with an epoxy resin 7 by a transfer molding method, thereby producing a Hall element having an overall thickness of 0.65 mm as shown in FIG.

In this way, a thinned and miniaturized device could be manufactured.

In the above, a Hall element has been described as an example of the magnetoelectric conversion element of the present invention. However, the present invention can also be effectively applied to a magnetoelectric conversion element using a magnetoresistance effect. Furthermore, a magnetoelectric conversion element using these effects in combination with other effects is, of course, within the scope of the present invention.

[Effects of the Invention] As described above, according to the present invention, a hole is provided in an island portion of a lead, and a substrate on which a magnetically sensitive portion is formed is inserted and adhered to the hole. The size can be reduced.

Further, according to the present invention, it is not necessary to reduce the thickness of the island portion other than the portion where the magnetoelectric conversion element is mounted in order to make the element thinner, so that it is possible to obtain sufficient lead strength. , Reliability can be improved.

In addition, since the height from the lead to the electrode surface is reduced, the bonding wire can be shortened, the adjustment of the wire loop at the time of wire bonding becomes easy, the yield of wire bonding is greatly improved, and it is impossible in the past. Mass production that was previously possible.

[Brief description of the drawings]

FIG. 1 is a plan view showing one embodiment of a magnetoelectric conversion element of the present invention, FIG. 2 is a perspective view of a copper plate used for manufacturing a lead in the embodiment of the present invention, and FIG. FIG. 4A shows a plan view, FIG. 4B shows a cross-sectional view taken along line cd, and FIG. 4 shows a method of manufacturing a Hall element using the leads shown in FIG. FIG. 5 is a cross-sectional view of the element showing one process, FIG. 5 is a side view showing an embodiment of the magnetoelectric conversion element of the present invention, and FIG. 6 is a side view showing an example of a conventional magnetoelectric conversion element. DESCRIPTION OF SYMBOLS 1 ... board | substrate, 2 ... Hall element magnetic sensing part, 3 ... electrode, 5
... adhesive, 6 ... bonding wire, 7 ... epoxy resin, 8 ... copper plate, 9 ... adhesive tape, 401, 402410, 4
11,412,413,420,421,422,423,430,431 …… Lead.

Continuation of the front page (56) References JP-A-61-256776 (JP, A) JP-A-58-53852 (JP, A) JP-A-1-184836 (JP, A) JP-A-57-121154 (JP) , U) JP 52-20316 (JP, B2) (58) Fields investigated (Int. Cl. ⁶ , DB name) H01L 43/06 H01L 43/04 H01L 21/60 301 H01L 23/50

Claims (2)

(57) [Claims] 1. A magneto-electric conversion element in which a magnetically sensitive part is formed on a GaAs substrate, and an electrode of the magnetically sensitive part is connected to a lead by a bonding wire, wherein a hole larger than the outer shape of the substrate is formed in an island part of the lead. Provided, the substrate is inserted into the hole, and the island portion and the substrate are formed on the inner side surface of the hole and the side surface of the substrate so that the back surface of the island portion and the bottom surface of the substrate are on the same plane. The substrate, the magnetic sensing part, the island part, and the bonding wire are sealed with resin only by filling and filling the gap, and the bottom surface of the substrate is directly connected to the sealing resin. A magnetoelectric conversion element being in contact with. 2. A method of manufacturing a magneto-electric transducer in which a magnetically sensitive portion is formed on a GaAs substrate, and electrodes of the magnetically sensitive portion are connected to leads by bonding wires. Providing a large hole, attaching an adhesive tape to the back surface of the lead,
A method for manufacturing a magnetoelectric conversion element, comprising: a step of inserting the substrate into the hole, fixing an inner surface of the hole and a side surface of the substrate with an adhesive, and removing the adhesive tape.