JPH0546942A - Composite thin film magnetic head and method of manufacturing the same - Google Patents

Abstract

(57) [Summary] [Object] To obtain a composite thin film magnetic head which secures a space for connection with an external circuit and is suitable for increasing magnetic recording capacity and thinning and lightening the composite thin film magnetic head. [Configuration] At least one thin film magnetic head 11 includes a substrate 2 having a thin film formation surface 3. The thin film forming surface 3 includes a hill portion 3a and a groove portion 3b. The thin film electromagnetic conversion element 31 is formed on the hill portion 3a. The electrode 7b is formed on the groove 3b. The lead terminal 7a is the electromagnetic conversion element 3
1 is formed on the substrate 2 so as to electrically connect the electrode 1 and the electrode 7b.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a composite type thin film magnetic head for magnetic recording and reproduction and a method for manufacturing the same, and particularly to two thin film magnetic heads each having a thin film electromagnetic conversion element formed on a substrate. The present invention relates to a combined composite thin film magnetic head and a method for manufacturing the same.

[0002]

2. Description of the Related Art In a fixed head type thin film magnetic head for digital audio or high speed transfer, large capacity memory device, recording is a magnetic induction type thin film magnetic head, and reproduction is a yoke type MR (magnetoresistive effect) type. It is considered that the use of each of the thin film magnetic heads is suitable for realizing high density and high quality magnetic recording / reproducing. As described above, two thin film magnetic heads are often combined and used as a composite type thin film magnetic head. As a head assembly configuration of this composite type thin film magnetic head, a configuration in which the back surfaces of the substrates face each other, a configuration in which the thin film formation surfaces face each other, and the like are considered.

When the back surfaces of the substrates are opposed to each other, the magnetic gaps of both the recording and reproducing thin film magnetic heads are separated by the thickness of the substrates. For this reason, it becomes difficult to suitably slide the medium sliding contact surface of the thin-film magnetic head and the magnetic medium. As a result, there is a drawback that high-quality recording and reproduction cannot be performed.

On the other hand, in the structure in which the thin film forming surfaces face each other, it is possible to make the distance between the recording and reproducing magnetic gaps as close as several tens to 100 μm. Therefore, it is possible to realize suitable sliding contact between the medium sliding contact surface and the magnetic medium. However, the electrode terminals, which are the connection portions with the external circuit formed on the substrate, also closely oppose each other. Therefore, a space for connecting to an external circuit cannot be secured.

Focusing on such a problem, a composite type thin film magnetic head having a medium sliding contact surface is one.
No. 17811. This composite type thin film magnetic head is shown in FIG. 14, FIG. 15, FIG. 16 and FIG.
Will be explained.

FIG. 14 is a perspective view showing a conventional thin film magnetic head alone, and FIG. 15 shows a composite thin film magnetic head in which the two thin film magnetic heads shown in FIG. 14 are combined so that their thin film forming surfaces face each other. It is a perspective view. With reference to these figures, the thin film magnetic head unit 50 is composed of a substrate 51, a protective layer 54 and electrode terminals 55, 56, 57 and 58.
The substrate 51 has a cutout region 501 on the side opposite to the sliding contact surface 53 with the magnetic medium. A thin film electromagnetic conversion element (not shown) is formed of a thin film on the thin film formation surface 59 of the substrate 51 and in the vicinity of the medium sliding contact surface 53. Electrode terminals 55, 56, 57 and 58 extend from this thin film electromagnetic conversion element. The electrode terminals 55, 56, 57, 58 are formed on the thin film formation surface 59 toward the terminal formation region 502 for connection with an external circuit. A protective layer 54 is formed on the thin film electromagnetic conversion element to protect the element.

The thin film magnetic head unit 50 is constructed in this way. A combination of two thin film magnetic heads 50 such that the thin film forming surfaces 59 face each other is a composite type thin film magnetic head 60 shown in FIG. This composite type thin film magnetic head 60 has a terminal forming region 50 on one substrate.
2 has a structure in which the notch region 501 of the other substrate faces each other. That is, the terminal formation region 502 on one substrate
Above is an open space. Utilizing this open space, connection with an external circuit such as wire bonding is performed.

Next, without providing a cutout region on the substrate,
FIG. 16 and FIG. 17 show a composite type thin film magnetic head having an open region at a connection portion with an external circuit.

Referring to FIG. 16, a composite type thin film magnetic head 70 includes a thin film magnetic head 61 extending in the width direction of lead terminals 65, 66, 67 and 68 and lead terminals 65, 66 and 6.
The thin film magnetic head 62 extends in the lengthwise direction of 7,68. The thin film magnetic heads 61 and 62 have no cutout area. The composite thin film magnetic head 70 has two
Terminal forming regions 69 of two thin film magnetic heads 61 and 62
They do not face each other and have open areas. Electrode terminals 65, 66, 67 and 68 formed in this region connect to an external circuit.

Referring to FIG. 17, composite thin film magnetic head 80 is composed of thin film magnetic heads 71 and 72 extending in the width direction of lead terminals 75, 76, 77 and 78. The thin film magnetic heads 71 and 72 also have no cutout area. The composite type thin film magnetic head 80 has an open region in which the terminal forming regions 79 of the two thin film magnetic heads 71 and 72 do not face each other. The electrode terminals 75, 76, 77 and 78 formed in this region connect to the external circuit.

[0011]

Generally, there are methods such as increasing the number of tracks and increasing the tape speed in order to increase the capacity of magnetic recording.

However, the conventional composite type thin film magnetic head 50 as described above has the cutout region 501 in the substrate 51. Therefore, the connection area of the electrode terminals 55, 56, 57, 58 with the external circuit is narrowed. Since this connection region becomes narrow, the number of electrode terminals formed in that region by patterning is significantly limited. Since the number of electrode terminals pulled out from the track is limited, the number of tracks is also limited. Therefore, it is difficult to increase the capacity of magnetic recording.

On the other hand, if the pitch of the electrode terminals is reduced in order to increase the number of tracks, there is a problem that it becomes difficult to connect the external circuit and the electrode terminals.

Further, the conventional composite type thin-film magnetic heads 70 and 80 having no notch region have a structure having a long depth or a wide frontage (thickness). Therefore, it is difficult to reduce the thickness and weight of the composite thin film magnetic head.

The present invention has been made to solve the above-mentioned problems, and secures a space for connecting to an external circuit, increases the magnetic recording capacity, and thins and lightweights the composite type thin film magnetic head. It is an object of the present invention to obtain a composite type thin film magnetic head that is suitable for use in manufacturing.

[0016]

At least one thin film magnetic head of a composite type thin film magnetic head according to the present invention comprises:
A substrate, a thin film element, a connection terminal, and wiring are provided. The substrate has a major surface that includes a first surface area and a second surface area that is below the level of the first surface area. The thin film element is formed on the first surface region of the substrate. The connection terminal is formed on the second surface region of the substrate. The wiring is formed on the substrate so as to electrically connect the thin film element and the connection terminal.

According to the method of manufacturing at least one thin film magnetic head of the composite type thin film magnetic head according to the present invention,
First, a substrate is formed that has a major surface that includes a first surface area and a second surface area that is lower than the level of the first surface area. A thin film element is formed on the first surface region of the substrate. A connection terminal is formed on the second surface area of the substrate. Wiring is formed on the substrate so that the thin film element and the connection terminal are electrically connected.

[0018]

According to the present invention, at least one thin film magnetic head constituting the composite type thin film magnetic head includes a first surface region and a second surface region lower than the level of the first surface region. A substrate having a main surface is provided. When a thin film magnetic head including such a substrate is combined with another thin film magnetic head to form a composite thin film magnetic head, a space is generated between the thin film forming surfaces of the thin film magnetic heads. In this space, connection with an external circuit is made.

Therefore, a connection area with an external circuit can be secured without providing a cutout area. That is, the connection area with the external circuit is not reduced by the cutout area. Since the connection area is not reduced, more electrode terminals can be formed. Therefore, it is possible to increase the number of tracks and increase the magnetic recording capacity.

Further, it is not necessary to shift the substrates and bond them. Therefore, the composite type thin film magnetic head has a compact structure. The structure of the present invention is suitable for reducing the thickness and weight of a composite type thin film magnetic head.

[0021]

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1A is a side view showing a schematic structure of a composite type thin film magnetic head according to an embodiment of the present invention, and FIG. 1B is a front view. With reference to these drawings, the composite type thin film magnetic head 1 is composed of a magnetic induction type thin film magnetic head 11, a yoke type MR type thin film magnetic head 21 and flexible printed boards 12 and 22. Lead terminals 14 are formed on the flexible printed circuit board 12. An external extraction pattern 15 is formed on the connection side of the lead terminal 14 with the external circuit. This flexible printed circuit board 12
Is joined to the magnetic induction type thin film magnetic head 11. The lead terminal 14 of the flexible printed board 12 is electrically connected to the lead terminal (not shown) of the thin film magnetic head 11. The flexible printed board 22 is configured similarly to the flexible printed board 12. The flexible printed board 22 and the yoke type MR type thin film magnetic head 21 are bonded in the same manner as described above. The magnetic induction type thin film magnetic head 11 is bonded to the yoke type MR type thin film magnetic head 21 so that their thin film forming surfaces face each other. A resin 30 is filled in the joined gap. The composite type thin film magnetic head 1 is configured as described above.

FIG. 2 is a sectional view showing a schematic structure of a magnetic induction type thin film magnetic head taken along line II-II of FIG. Referring to FIG. 2, substrate 2 is made of polycrystalline ferrite. The thin film forming surface 3 of the substrate 2 is composed of a hill portion 3a and a ship bottom type groove portion 3b. The lower core 4 and the coil 5 are provided near the medium sliding surface 32 and above the hill portion 3a.
And the thin film electromagnetic conversion element 31 including the upper core 6 is formed. The coil 5 is formed so as to go around the slope 6 a of the upper core 6. Thin film electromagnetic conversion element 31
In order to take out the output from the coil 5, the lead terminal 7a is pulled out to the groove 3b. The leading end of the lead terminal 7a serves as an electrode 7b for connection with an external circuit. The lead terminal 7a and the electrode 7b are formed on the surface of the thin film forming surface 3. A protective film 8 made of SiO ₂ is coated on the thin film electromagnetic conversion element 31 and the lead terminal 7a. The protective film 8 is not covered on the electrode 7b and the electrode 7b is exposed. This exposed electrode 7
A flexible printed circuit board 12 having a Kapton film as a base material is joined to the top of b. The lead terminal 14 formed on the flexible printed board 12 is electrically connected to the electrode 7b through the Au bump 9. By connecting the lead terminal 14 and the electrode 7b, the magnetic signal of the thin film electromagnetic conversion element 31 is extracted to the outside. Spacer materials 13 are adhered and fixed to both end portions of the thin film formation surface 3 in the vicinity of the end surface 36 of the substrate 2 on the external extraction side.
The spacer material 13 secures a space for connection with an external circuit. In order to make the thin film magnetic head bonding surface 33 made up of the spacer material 13 and the protective film 8 uniform, the resin 3
0 is formed. As described above, the magnetic induction type thin film magnetic head 11 according to the embodiment of the present invention is constructed.

The yoke type MR type thin film magnetic head 21 shown in FIG. 1 has the same structure as the magnetic induction type thin film magnetic head 11 except for the thin film electromagnetic conversion element 31.

FIGS. 3 to 10 show a method of manufacturing a composite type thin film magnetic head according to an embodiment of the present invention in the order of steps I of FIG.
It is sectional drawing which follows the I-II line. An embodiment of the present invention will be described below with reference to these drawings.

First, referring to FIG. 3, on the thin film formation surface 3 of the substrate 2 made of polycrystalline ferrite (wafer 35 state),
The hill portion 3a and the bottom groove 3b are formed by a slicing machine using a metal bond grindstone or a register bond grindstone. The roughness of the processed surface at this time may be such that the film on which the lead terminals are patterned does not cause step breaks. Specifically, when the thickness of the lead terminal is about 6000Å, the maximum step R of the unevenness of the processed surface caused by the processing
It is sufficient that _max is 1000 to 2000Å. The groove depth 34 is 500 μm.

Next, referring to FIG. 4, the hill portion 3 of this substrate 2
A thin film electromagnetic conversion element 31 including a lower core 4, a coil 5 and an upper core 6 is formed on a by film formation, photolithography and etching. From the coil 5 of the thin-film electromagnetic conversion element 31, the lead terminal 7a is drawn out for taking out the output. This lead terminal 7a has a groove 3
It is formed so as to extend toward b. Thin film electromagnetic conversion element 3
A protective film 8 made of SiO ₂ is coated on 1 and the lead terminals 7a. The protective film 8 is removed by etching only the portion covering the tip of the lead terminal 7a on the groove portion 3b side. By this etching, the lead terminal 7a
The tip on the groove 3b side is exposed. The exposed portion of the lead terminal 7a becomes an electrode 7b for connection with an external circuit. In addition, on the thin film formation surface 3 of the substrate 2, the groove portion 3b
Spacer materials 13 for securing a space for connection with an external circuit are adhered and fixed to both end portions on the side.

Referring to FIG. 5, protective film 8 and spacer material 1
The upper surface of 3 is flattened by a high speed lapping machine using a diamond slurry liquid. By this flattening, both upper surfaces of the protective film 8 and the spacer material 13 are aligned so as to exist on the same plane. For this flattening, a general precision horizontal type or surface grinding type other than the high speed lapping machine may be used.

Referring to FIG. 6, the head chip formed as described above is separated from wafer 35.

Referring to FIG. 7, Au bumps 9 are formed on the exposed surfaces of the electrodes 7b of the divided head chip. The flexible printed board 12 having a Kapton film as a base material is bonded to the board 2 by the Au bumps 9. The lead terminal 14 formed on the flexible printed board 12 is electrically connected to the electrode 7b through the Au bump 9. The magnetic signal of the thin film electromagnetic conversion element 31 is extracted to the outside by the lead terminal 14. Next, the groove 3b is filled with the resin 30. The resin 30 is formed along the heights of the upper surfaces of the spacer material 13 and the protective film 8.

In this way, the magnetic induction type thin film magnetic head 11 is manufactured. Further, as shown in FIG. 8, the yoke type MR thin film magnetic head 21 is manufactured in the same manner as the magnetic induction type thin film magnetic head 11 except for the thin film electromagnetic conversion element 131.

With reference to FIG. 8, the thus prepared 2
The two thin film magnetic heads 11 and 21 are combined so that the thin film forming surfaces 3 and 103 face each other.

FIG. 9 and FIG. 10 are enlarged side views showing the P portion of the two combined thin film magnetic heads 11 and 21.

Referring to FIG. 9, when the thin film magnetic heads 11 and 21 are combined, the gap depth position marker 12 is used.
The thin film magnetic heads 11 and 21 are aligned by 0 and 121. On the contact surface 123 of the two thin film magnetic heads 11 and 21 that are combined together, a low-viscosity instant adhesive or a volatile ultraviolet curable resin is dropped. As a result, the thin film magnetic heads 11 and 21 are fixed to each other. The fixed thin film magnetic heads 11 and 2
Mold resin is filled in the gap between the first contact portions 123. Including the curing shrinkage of the resin, the misalignment is suppressed to about ± 1 μm.

Referring to FIG. 10, the end surface 110 of the combined thin film magnetic head is cylindrically ground and tape-polished.
By this processing, the end surface 110 is processed into the medium sliding contact surface 32 formed of one curved surface. At the time of this polishing, a method of using a resistor is adopted in order to know the absolute value of the changing gap depth. As shown in FIG. 9, one resistor is provided on each side of the thin film electromagnetic conversion element forming region on the surface of the thin film forming surface 3 of the substrate 2 so as to be exposed at the end face 110. It is formed. Two lead terminals for drawing out a resistance value from the resistor 500 extend to the outside.
In this way, the resistor 500 previously formed on the substrate 2
Are ground together with the end surface 110 by polishing to form the medium sliding contact surface 32. By the polishing of the resistor 500, the area of the resistor 500 changes, so that the resistance value changes. This changing resistance value is drawn out by the lead terminal. The resistance value drawn to the outside is converted into a gap depth value by arithmetic processing. This gap depth value is constantly monitored, and when the desired gap depth value is reached,
The processing by polishing is completed.

In this way, the composite type thin film magnetic head 1
Is created. In the above-mentioned knowledge, the electrode 7b and the lead terminal 14 of the flexible printed board 12 are electrically connected by the Au bump 9, but they may be connected by wire bonding.

Next, a marker used for aligning the gap depth when combining two thin film magnetic heads will be described.

FIG. 11A is a left side view of a composite type thin film magnetic head according to an embodiment of the present invention, FIG. 11B is a front view and FIG. 11C is a right side view. Referring to FIG. 11, grooves 301 are formed on side surfaces 140 and 141 of thin film formation surface 3 of substrate 2 and in the vicinity of end surface 110. In addition, the side surface 15 of the thin film formation surface 103 of the substrate 102
0 and 151, and the groove 35 near the end face 110.
1 is formed. These grooves 301 and 351 are formed on the side surface of the substrate at a constant pitch by a grindstone before the thin film is formed on the substrate. This processed groove 3
The thin film electromagnetic conversion element is formed by using one edge of 01 and 351 as a reference line for aligning a mask when forming a thin film. Therefore, the relative positional relationship (distance) between the reference line and the gap depth can be known in advance. Therefore, when combining the thin film magnetic heads 11 and 21,
By aligning the grooves 301 and 351 with each other, the thin film electromagnetic conversion elements can be aligned with each other.

FIG. 12A is a left side view of a composite type thin film magnetic head according to one embodiment of the present invention, FIG. 12B is a front view and FIG. 12C is a right side view. With reference to FIG. 12, on the thin film formation surface 3 of the substrate 2, in the vicinity of the end face 110, a film 401 for gap depth alignment is formed on the side surface 14.
It is formed along 0. The film 401 is also formed on the side surface 141 side. On the thin film formation surface 103 of the substrate 102 and near the end face 110, a gap depth alignment film 451 is formed along the side surface 150. A film 451 is also formed on the side surface 151 side. In the fabrication of the films 401 and 451, first, when the pattern of the photomask is designed, a dedicated pattern for forming the films 401 and 451 for aligning the gap depth is provided on the photomask. The dedicated pattern is positioned on the photomask so as to have a constant distance from the gap depth reference position. By using this photomask, the films 401 and 451 are formed during the process of forming the thin film electromagnetic conversion element. Then, when the head chip is separated from the wafer 35, a film 401 for gap depth alignment is formed on the side surface of the head chip.
It is devised so that the cross section of 451 can be observed. The films 401 and 451 for aligning the gap depth are made of the same material as the upper core 6 for easy identification.

Although two typical examples have been shown as the markers for aligning the gap depth, any marker may be used as long as the markers are capable of knowing the mutual gap depth positions from the side surface.

FIG. 13 is a front view showing a schematic structure of a composite type thin film magnetic head according to another embodiment of the present invention. FIG.
Referring to, one of the thin film magnetic heads 310 constituting the composite type thin film magnetic head 300 has a hill portion 314a and a ship bottom groove portion 314b on the thin film formation surface 314 of the substrate 311 thereof. The other thin film magnetic head 300 has a shape in which the thin film formation surface 324 of the substrate 321 is flat.

As in the other embodiments described above, only one of the thin film magnetic heads constituting the composite type thin film magnetic head may have a shape having a ship bottom groove on the element formation surface.

[0042]

As described above, according to the present invention, at least one thin film magnetic head forming the composite thin film magnetic head has the first surface region and the second surface lower than the first surface region. A substrate having a major surface including a surface region. Therefore, this composite type thin film magnetic head can secure a connection region with an external circuit without providing a cutout region. Therefore, the connection area with the external circuit is not reduced, and the magnetic recording capacity can be expected to increase.

Further, it is not necessary to shift the thin film magnetic heads and combine them. Therefore, this composite type thin film magnetic head has a compact structure and is suitable for reduction in thickness and weight.

[Brief description of drawings]

FIG. 1 is a side view (a) showing a schematic configuration of a composite thin film magnetic head according to an embodiment of the present invention, and a front view (b) showing a schematic configuration of a composite thin film magnetic head.

FIG. 2 is a sectional view showing a schematic configuration of a magnetic induction type thin film magnetic head taken along line II-II in FIG.

FIG. 3 is a sectional view taken along the line II-II of FIG. 1 showing a first step of the method of manufacturing the composite thin film magnetic head according to the embodiment of the present invention.

FIG. 4 is a sectional view taken along the line II-II in FIG. 1 showing a second step of the method for manufacturing the composite thin film magnetic head according to the embodiment of the present invention.

5 is a sectional view taken along the line II-II in FIG. 1 showing a third step of the method for manufacturing the composite thin film magnetic head according to the embodiment of the present invention.

FIG. 6 is a sectional view taken along the line II-II in FIG. 1 showing a fourth step of the method for manufacturing the composite thin film magnetic head according to the embodiment of the present invention.

FIG. 7 is a sectional view taken along the line II-II in FIG. 1, showing a fifth step of the method for manufacturing the composite thin-film magnetic head according to the embodiment of the present invention.

FIG. 8 is a sectional view taken along the line II-II in FIG. 1, showing a sixth step of the method for manufacturing the composite thin-film magnetic head according to the embodiment of the present invention.

FIG. 9 is a sectional view taken along the line II-II in FIG. 1 showing a seventh step of the method for manufacturing the composite thin film magnetic head according to the embodiment of the present invention.

FIG. 10 is an enlarged side view of a portion P in FIG. 8 showing an eighth step of the method for manufacturing the composite thin film magnetic head according to the embodiment of the present invention.

FIG. 11 is a side view of a composite type thin film magnetic head showing a gap depth alignment marker according to an embodiment of the present invention.

FIG. 12 is a side view of a composite type thin film magnetic head showing a gap depth alignment marker according to another embodiment of the present invention.

FIG. 13 is a front view showing a composite type thin film magnetic head according to another embodiment of the present invention.

FIG. 14 is a perspective view showing a conventional thin film magnetic head alone.

FIG. 15 is a perspective view showing a conventional composite type thin film magnetic head.

FIG. 16 is a perspective view showing a composite type thin film magnetic head in a second conventional example.

FIG. 17 is a perspective view showing a composite type thin film magnetic head in a third conventional example.

[Explanation of symbols]

 1 Composite Thin Film Magnetic Head 2 Substrate 3 Thin Film Forming Surface 3a Hill 3b Groove 4 Lower Core 5 Coil 6 Upper Core 7a Lead Terminal 7b Electrode 11 Magnetic Induction Thin Film Magnetic Head 21 Yoke Type MR Thin Film Magnetic Head

Claims (2)

[Claims] 1. A composite thin film magnetic head in which a plurality of thin film magnetic heads are combined such that thin film elements formed on a plurality of substrates face each other, and at least one thin film magnetic head is provided. A head is formed on a substrate having a main surface including a first surface area and a second surface area lower than the level of the first surface area; and a first surface area of the substrate. A composite thin film, comprising: a thin film element, a connection terminal formed on a second surface region of the substrate, and a wiring formed on the substrate so as to electrically connect the thin film element and the connection terminal. Magnetic head. 2. A method of manufacturing a composite type thin film magnetic head, wherein a plurality of thin film magnetic heads are combined so that respective thin film elements formed on a plurality of substrates face each other. Forming a substrate having a main surface including a first surface region and a second surface region lower than the level of the first surface region; A step of forming a thin film element on the first surface area of the substrate; a step of forming a connection terminal on the second surface area of the substrate; and a step of electrically connecting the thin film element and the connection terminal to each other. And a step of forming wiring on a substrate.