JPS60101704A - Manufacture of multielement magnetic head device - Google Patents

Abstract

PURPOSE:To obtain high sealing effect by covering the majority of a device with a resin molding which superior sealing effect such as moisture resistance. CONSTITUTION:A capacitor 80 is connected to a lead frame 21, which is then molded. The housing for an integrated circuit 41 and a multielement magnetic head 1 is formed, and the integrated circuit 41 and multielement magnetic head 1 is mounted on the lead frame 21 in the housing, wired mutually, and then molded lastly.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention is suitable for application to obtaining a multi-element magnetic head using a thin film magnetic head such as an electromagnetic induction type or a magnetic repulsion effect (MR) type magnetic head. This invention relates to a method for manufacturing a multi-element magnetic head.

Background technology and its problems For example, multi-channel recording or reproducing PCM signals,
That is, a 1111 type multi-element magnetic head is used as the multi-element magnetic head.

The thin film type multi-element magnetic head will be explained with reference to FIGS. 1 and 2. In the figure (11) is a multi-element magnetic head with an electromagnetic induction type configuration as a whole.
1) is, for example, Mn-Zn ferrite.

A large number of thin film magnetic head elements are arranged in parallel on a magnetic substrate (2) made of Mn-Ni ferrite or the like. In this case, a groove (3) is formed in the substrate (2) facing its main surface (2a) along the longitudinal direction of the substrate (2), and a non-magnetic material (4), such as glass, is formed in the groove (3). is filled. In addition, on the surface (2a) of the substrate (2), if the substrate (2) has conductivity, a non-magnetic insulating material such as 5t (h) is placed on the surface (2a) of the substrate (2).
1151 is deposited, and a strip-shaped thin film conductor (8) serving as a signal wire ring provided corresponding to each channel (for example, 22 channels) is deposited on this. These conductors (8) are made of permalloy or the like, which are provided at least partially along the groove (3), and extend across the groove (3) and the conductor (8) above it to correspond to each channel. A thin film of magnetic N(9) consisting of the above is deposited, respectively. In this case, the conductor (8
) is coated with an insulating layer (5) such as 5i02 to electrically insulate it from the thin magnetic layer (9). Each magnetic layer (9)
One end is connected to the groove (3) of the magnetic substrate (2) via the non-magnetic gap spacer -aΦ formed by the above-mentioned magnetic layer (5), for example.
) along one side edge (2b).

The other end is magnetically closely coupled to the surface (2a) of the ζ substrate (2), for example, through a window (5a) formed in the insulation M (5).

In this way, a closed magnetic path is formed by the common substrate (2) and each magnetic layer (9), and for each closed magnetic path, a signal wire ring made of a thin film conductor (8) is provided, and each closed magnetic path is A magnetic head element of each channel is constructed in which the gap length is defined by a gap spacer (Iψ) and an operating magnetic gap g is formed in the channel.

On top of each magnetic head element, a protective substrate (11) with excellent wear resistance is placed opposite the substrate (2) using an adhesive (1).
2).

On the other hand, both ends (8a) (8b) of each thin film conductor (8)
) respectively connect the external circuit, that is, this magnetic head (11
As a terminal connected to an external circuit such as an output circuit including a serial-to-parallel converter that supplies a recording signal to the magnetic head (11), or an input circuit including a parallel-to-serial converter to supply a reproduction signal from this magnetic head (11), o of board (2)
It extends to the other side edge (2c) opposite the llI edge (2b). In this case, the width of the protective substrate (11) is the same as that of the magnetic substrate (2).
The terminals (8a) and (8b) are exposed to the outside of the protective substrate (11).

Then, both substrates (
2) and (11) are cut and polished to form a surface (13) in contact with the magnetic medium where the magnetic gap g of each head element faces.
is formed.

Such a multi-element magnetic head (11) and the above-mentioned external circuit have their corresponding terminals connected in a Y manner using, for example, a flexible wiring board. Connecting the head and an external circuit outside the magnetic head tends to cause accidents such as wire breakage, which poses problems in reliability.

In order to improve these problems, the applicant proposed the following method for manufacturing a multi-element magnetic head device.

A housing including a lead frame is molded by transfer molding, and inside this housing there is an integrated circuit that constitutes the external circuit accompanying the magnetic head mentioned above, and this integrated circuit is used to ground external signals (noise) in an alternating current manner. Mount the capacitor and thin film multi-element magnetic head to be inserted between the circuit power line and ground, then connect the integrated circuit and multi-element magnetic head with Au wire etc., and then final seal with liquid resin. It is done like this. In this multi-element magnetic head device, since the multi-element magnetic head is integrated with an external circuit connected to the multi-element magnetic head, reliability is improved compared to the conventional device.

However, in this case, since the capacitor is mounted on the lead frame using a conductive paste, etc., the adhesive strength of the adhesive part varies.
Furthermore, it was necessary to increase the area of the bonded portion of the lead frame, which caused problems in productivity and reliability. or,
It is also possible to mount the capacitor by welding, etc., but in this case, the welding electrode can only be contacted from the top side, which increases the area occupied by the connection part of the lead frame, which hinders miniaturization. Ta.

purpose of invention In view of the above points, the present invention provides a multi-element magnetic head.

In a multi-element magnetic head device that incorporates an integrated circuit and a capacitor and integrates them with a resin mold, we aim to improve the reliability of the capacitor connection in particular, further improve productivity, and reduce the overall size. The present invention provides a method for manufacturing a multi-element magnetic head, which is designed to facilitate the use of multi-element magnetic heads.

Summary of the Invention In the present invention, after a capacitor is bonded to a lead frame, the lead frame including the capacitor is molded with resin to form a housing in which an integrated circuit that constitutes an external circuit and a multi-element magnetic head are disposed. do. Then, the integrated circuit and the multi-element magnetic head are placed on a lead frame in the °C housing, and inter-phase wiring is provided. After heating at °C, the integrated circuit and the multi-element magnetic head are finally resin molded.

According to the manufacturing method of the present invention, the reliability of the connection portion of the capacitor is improved, and a multi-element magnetic head device with higher reliability can be obtained. Furthermore, productivity is improved and this type of multi-element magnetic head device can be made more compact.

EXAMPLE An example of the manufacturing method of the present invention will be explained in detail with reference to FIG. 3 and subsequent figures. In this example, a lead frame (2
1) will be provided. This lead frame (21) is obtained by selectively etching a metal plate, and the circuit mounting part (22) on which the integrated circuit is finally mounted and mounted is obtained by selectively etching a metal plate.
), a lead part (23) that becomes a terminal led out from the integrated circuit, a connecting part (26) for connecting a capacitor between the required lead parts (23), and these lead parts (
23) and a frame portion (24) that interconnects each lead portion (23).
23) and a restricting part (25) which is arranged across the resin molding part (25) and which restricts the flow of resin during resin molding, is integrally formed as a whole.

In the present invention, as shown in FIGS. 4 and 5, first, the capacitor (80) is connected in a lead frame state between the connecting portions (26) of the required lead portions by spot welding. In this case, the lead (80) of the capacitor (80)
Spot welding between a) and each connection part (26) is performed using a welding electrode (
27) are placed one above the other (see Figure 4). Therefore, the area of the connecting portion (26) of the lead frame (21) can be sufficiently small.

The capacitor (80) is for grounding an external signal (noise) in an alternating current manner, and is inserted between the power supply line of the integrated circuit and the ground, which will be described later.

Next, as shown in FIG. 6, a resin mold body (31) constituting the housing of the magnetic head device is formed by molding using a resin mold, such that the capacitor (8o) is integrally resin molded. That is, when molding the mold body (31), the lead frame (21) with the above-mentioned capacitor (80) attached thereto is placed in the mold, thereby embedding the lead frame (21). Also, mold body (31)
There is a recess (32) in which the integrated circuit is housed and a magnetic head arrangement part (3) adjacent to the concave part (32) with a jetty (33) in between.
4) is provided. These integrated circuit storage recesses (
32) and the magnetic head arrangement part (34) are both parts (32).
and (34), opposing side wall portions (35a
) and (35b), and a rear wall (35c) of the recess (32) in which the capacitor (80) is buried. Each wall (
The heights of the end faces 35a), (35b) and (35c) are selected so that they form the same plane. The front side of the magnetic head placement portion (34) is open, and one side wall (35a) or (35b) of the integrated circuit storage recess (32) is open.
) is provided with a cutout (36) for resin injection.
) is provided. Note that the height of the jetty (33) is selected to be lower than the height of each of the walls (35a) to (35c).

The lead frame (21) has a mounting portion (2) for the integrated circuit.
2) is arranged so that one surface is exposed on the bottom surface of the recess (32), and the lead portion (23) penetrates the wall portion (35c) so that its outer end protrudes outside the mold body (31). It is arranged like this. After molding the mold body (31), this lead frame (21) is formed by cutting and removing the frame portion (24) and cutting the limiting portion (25) between each lead portion (23). 23) Electrically isolate between.

Next, in order to improve the wire bonding properties of the lead frame (21), paris and mold release agent are removed using liquid forning, etc.
Clean the surface of the lead frame (21) - At this time, the capacitor (8o) is already embedded in the mold body (31) and is not affected by liquid forning. Then, as shown in FIGS. 7 and 8, the lead frame (2) is placed in the recess (32) of the mold body (31).
The integrated circuit (41) in which a circuit associated with a magnetic head such as the serial-to-parallel converter described above is formed is mounted and bonded on the integrated circuit mounting portion (22) of 1). is stored in the four parts (32). On the other hand, the magnetic head arrangement portion (34) of the molded body (31)
) is placed on the magnetic head (11) with the front end facing the magnetic gear g protruding forward from the placement portion (34).

This magnetic head (11 is, for example, the Vs film pear-shaped magnetic head shown in FIGS. 1 and 2, and each terminal (11) on its substrate (2)
8a) and (8b) are respectively connected to the corresponding output or input terminal portion of the integrated circuit by a lead wire (42) over the jetty (33).In addition, the integrated circuit (41
) and the corresponding lead portions (23) of the lead frame (21) are similarly interconnected by lead wires (43).

Next, resin is injected into the resin mold body (31) in which the integrated circuit (41) and the magnetic head (1) are placed, so-called casting. This casting is a molded body (3
This is done by the cooperation of 1) and a casting mold, which fills with molten resin and hardens it. As a result, as shown in FIG. 9, when the resin (71) is filled into the housing made of the molded body (31), the integrated circuit (41), the magnetic head +11, and the leads (23) Lead wires etc. for connection are made of resin (71) and molded body (31).
) and are sealed from the outside. And in this case, after this tree) ill note large treatment, the magnetic spatula l' (1)
The front side of O is polished to form a surface (13) that contacts the magnetic medium.

In addition, the integrated circuit mounting part (22) of the lead frame (21)
) can be configured such that a metal heat radiator having high thermal conductivity is placed on the back surface of the mold body (31) and its outer surface is exposed to the outer surface of the molded body (31).

In the above example, the case where the magnetic head (11) is an electromagnetic induction type magnetic head has been described, but it goes without saying that the present invention can also be applied to a case where the magnetic head (1) is an MR type thin film head. In addition, when the reproducing head is an MR head and the recording head is an electromagnetic induction head, the magnetic head devices obtained by the above-mentioned manufacturing method of the present invention are stacked, for example, with the resin (71) side facing inside. By integrating them together, it is possible to obtain recording and reproducing heads that are mutually held in a predetermined positional relationship.

Effects of the Invention As mentioned above, in the manufacturing method of the present invention, a multi-element magnetic head,
an integrated circuit constituting an external circuit attached to the magnetic head;
The capacitor is integrally sealed in resin,
In this case, after bonding the capacitor in the form of a lead frame to the required lead portion of the lead frame, the lead frame including the capacitor is molded with resin to form a housing, and the magnetic head and The integrated circuit is mounted, and finally the magnetic head and the integrated circuit are molded. For this reason, it is possible to use spot welding to join the lead part of the lead frame and the lead of the capacitor.
A reliable connection can be made.

At the same time, during welding, the welding electrode can be applied from above and below as shown in FIG. 3, and the area occupied by the welding electrode can be ignored compared to, for example, when it is applied only to the upper surface. Therefore, since the lead frame can be made smaller, the entire magnetic head device molded with resin can be made smaller. In addition, after connecting the capacitor, the capacitor is molded to form a housing, so in order to improve wire bonding properties, the connection part is also used during liquid forning treatment on the exposed part of the lead frame. and the capacitor itself will not be damaged.

In this way, in the present invention, by covering most of the entire body with a resin mold that has excellent sealing effects such as moisture resistance, a tight sealing effect is obtained, and at the same time, the reliability of the capacitor connection part and the lead wire connection part is improved. As a whole, a multi-element magnetic head device having higher reliability and higher productivity than C can be obtained.

[Brief explanation of the drawing]

FIG. 1 is an enlarged sectional view of an example of a multi-element magnetic head used to explain the present invention, FIGS. 2 and 2 are enlarged plan views thereof, and FIG. 3 is an example of a lead frame used in the multi-element magnetic head device of the present invention. Fig. 4 is an enlarged plan view, Fig. 4 is a sectional view showing the spot welding process of the capacitor to the lead frame, Fig. 5 is an enlarged flat view showing the capacitor attached to the lead frame, and Fig. 6 is an example of the molded body. The enlarged perspective view, FIGS. 7 and 8 are magnetism in one step of the manufacturing method of the present invention.
FIG. 9 is an enlarged perspective view of an example of a multi-element magnetic head device obtained by the manufacturing method of the present invention. (11 is a multi-element head, (21) is a lead frame, (
31) is a molded body, (41) is an integrated circuit, (71) is a resin, and (80) is a capacitor. Figure 1 Figure 4 Figure 7 Figure 8

Claims (1)

[Claims] a step of joining a capacitor to a lead frame; a step of molding the lead frame including the capacitor to form a housing for an integrated circuit and a multi-element magnetic head; The process of placing it on the internal lead frame and wiring it,
A method for manufacturing a multi-element magnetic head device, comprising the step of molding the integrated circuit and the multi-element magnetic head.