JPH0316008A - Thin film magnetic head - Google Patents

Abstract

PURPOSE:To prevent a crack from being generated in a protective film being in the vicinity of a take-out electrode by protruding an end edge of a lead conductor by >=5mum from an end edge of the take-out electrode. CONSTITUTION:An end edge B of lead conductors 7, 8 is protruded by protrusion length l1, l2 to both its sides in the minor axis direction Y from an end edge A of overhang parts 91, 101 of take-out electrodes 9, 10, and protruded by protrusion length l3 to one side in the major axis direction X. The protrusion length l1, l2 and l3 is selected to >=5mum, and >=10mum desirably. When the protrusion length l1, l2 and l3 become smaller than 5mum, the influence exerted by a shadow action of the overhang parts 91, 101 starts to appear, and a crack comes to be generated easily. In such a way, since the end edge of the lead conductors 7, 8 is protruded by >=5mum from the end edge of the take-out electrodes 9, 10, the thin film magnetic head being free from a crack in a protective film 11 being in the periphery of the take-out electrodes 9, 10 is obtained.

Description

[Detailed Description of the Invention] Industrial Application Fields The present invention relates to a thin-film magnetic head, and relates to a thin-film magnetic head in which the edge of a lead conductor electrically connected to a conductor coil film is connected to By protruding by 5 μm or more, it is possible to prevent cracks from occurring in the protective film around the extraction electrode.

5. Prior Art> FIG. 5 is a perspective view of a main part of a thin film magnetic head well known from Japanese Patent Laid-Open No. 55-84020, etc., and FIG. 6 is an enlarged sectional view of the same main part. In the figure, 1 is A12
A substrate made of ceramic such as 0s/TiC, 2 a lower magnetic film, 3 a gap film made of alumina, 4 an upper magnetic film, 5 a conductive coil film, and 6 an organic resin such as novolac resin. an insulating film composed of; 7 and 8 are lead conductors; 9;
10 is an extraction electrode, 11 is a protective film such as alumina that covers the whole, and the tips of the lower magnetic film 2 and the upper magnetic film 4 form ball parts 21 and 41 facing each other with a gap film 3 of minute thickness in between. Reading and writing are performed in the ball parts 21 and 41. 22 and 42 are yoke parts, and ball parts 21 and 41
They are joined at the opposite end.

The insulating film 6 is composed of a plurality of layers of insulating films 6t to 63, and has an insulation fl! yoke portions 22, 42 on top of at, 62.
A conductive coil film 5 is formed so as to spiral around the joint portion. The conductor coil film 5 usually has a two-layer structure of a base film and a Culli film.

The lead conductors 7 and 8 also have a two-layer structure similar to the conductor coil film 5, and are electrically connected to both ends of the conductor coil WA5.

The extraction electrodes 9 and 10 are parts to which external conductors such as lead wires will be connected later. The lead electrodes 9 and 10 are formed as Cu plating films on the plating layers formed on the surfaces of the lead conductors 7 and 8.

FIG. 7 is an enlarged sectional view of the extraction electrodes 9 and 10. As shown in the figure, the extraction electrode 9, IO has an overhang portion 91,
101, and has an umbrella shape with hollow portions 92, 102 between overhang portions 91, 101 and the surfaces of lead conductors 7, 8. The edge A of the overhang portions 92, 102 is located at approximately the same position as the edge B of the lead conductors 7, 8, or on the inside thereof. 12 and 13 are gold BWAs whose main ingredient is gold provided on the surfaces of the extraction electrodes 9 and 10.
It is. Problems to be Solved by the Invention> However, the conventional thin film magnetic head
As is known from Japanese Patent Laid-open No. 219 and JP-A-59-165221, cracks 14 occur in the protection film 11 near the extraction electrodes 9 and 10 as shown in FIG. If there is a crack 14 as described above, problems such as dust entering the crack 14 and easy peeling of the lead electrodes 9 and 10 occur.

The cracks 14 occur mainly due to the shape of the lead electrodes 9, 10 relative to the lead conductors 7, 8, and the shaping process of the lead electrodes 9, 10. FIG. 8 shows a conventional electrode forming process. First, as shown in FIG. 8(a), a resist mask 15 is formed by photolithography on a substrate i, which is a wafer, so as to cover the lead conductors 7 and 8 while leaving the extraction electrode pattern P. The thickness dl of the resist mask 15 is 5 to 10 μm, which enables high-precision patterning using photolithography.Although not shown, the resist mask 15 is suitable for use with the thin film magnetic head shown in FIGS. 5 and 6. It is attached so as to cover the element as well.

Next, by performing plating treatment, as shown in Fig. 8(b)
As shown in FIG.
Promote 0. Cu Metsuki @Q 1Q tr1
rWik r4 AL person Gakukenni 3 0 ~
It is made to have a thickness such that a lead-out electrode having a thickness of 40 μm can be obtained.

Here, the thickness d of the resist mask 15 is 5 to 10 μm.
On the other hand, since the thickness d2 of the Cu plating films 9 and 10 is at least 30 to 40 μm, the Cu plating IIi 9 and 10 must be grown beyond the resist mask 15. Since the Cu plating films 9 and 10 grow isotropically, the thickness of the resist mask 15 is dl-5 to 10μ.
After exceeding the thickness obtained by subtracting the thickness (several μm) of the lead conductors 7 and 8 from m, it also grows along the surface of the resist mask 15, and overhangs 91 and 101 occur (FIG. 8(b)) reference). The Cu plating lli 9, 10 extends so that the edge A of the overhang portion 91, 101 is approximately at the same position as the edge B of the lead conductor 7, 8, or to a position outside of it.

Therefore, when the resist mask 15 is removed, as shown in FIG. 8(C), the thickness below the overhang parts 91 and 101 corresponds to the thickness da obtained by subtracting the thickness of the lead conductors 7 and 8 from the thickness d1 of the resist mask 15. Cavity parts 92, 10
2, and in addition, the lead-out electrodes 9, 10 are obtained in which the meshing edges A of the overhang parts 91, 101 are approximately at the same position as the ends AiB of the lead conductors 7, 8, or protrude outward from them.

When a protective film 11 is sputtered on the above-mentioned extraction electrodes 9 and 10 as shown in FIG. 1ii serves as a shadow for the lead conductors 7 and 8 below. Moreover, the extraction electrodes 9 and 10 have overhang portions 91 and 1
01 end a A b < IJ - F Since it is formed at almost the same position as the end edge B of the conductors 7 and 8, or so as to extend outward from it, the shadow effect on the lead conductors 7 and 8 is extremely high. Become. For this reason, the lead conductor 7,
Step covering between 8 and the extraction electrodes 9 and 10 deteriorates, and cracks 14 occur.

Therefore, the i! ! One problem is to provide a thin II magnetic head that solves the above-mentioned conventional problems and can prevent cracks from occurring in the protective film near the extraction electrode.

Means for Solving the Problems> In order to solve the above problems, thin 11! The magnetic head includes a thin film magnetic head element having a magnetic circuit including a magnetic film and a conductor coil film, a lead conductor electrically connected to the conductor coil film, an extraction electrode formed on the lead conductor, and an external part of the extraction electrode. A thin film magnetic head having a protective film that covers the entire surface except for a conductor connection surface, and a substrate that supports the entire surface, wherein the edge of the lead conductor is 5.5 mm larger than the edge of the extraction electrode.
It is characterized by a protrusion of more than μm.

Effect> If the edge of the lead conductor protrudes by 5 μm or more from the edge of the extraction electrode, the edge of the lead conductor that protrudes by 5 μm or more will be affected by the shadow effect of the extraction electrode during protective film sputtering. I'll never accept it. Therefore, step covering is improved and cracks do not occur in the protective film. The present invention is applicable not only to thin-film magnetic heads for longitudinal recording and reproduction, but also to thin-film magnetic heads for perpendicular recording and reproduction. Embodiment> FIG. 1 is a perspective view of a main part of a thin llI magnetic head according to the present invention, FIG. 2 is an enlarged cross-sectional view taken along the long axis direction The figure is an enlarged sectional view taken along the minor axis direction Y in FIG. 1. In the figures, the same reference numerals as in FIGS. 5 to 7 indicate the same components. Although not shown, the thin film magnetic head element has the structure shown in FIG. The end edges B of the lead conductors 7 and 8 are made to protrude from the end edges A of the overhang parts 91 and 101 of the extraction electrodes 9 and 10 by protruding lengths j21 and J22 on both sides in the short axis direction Y, and are extended in the long axis direction X. Make it protrude by a protrusion length of ℃3 on one side. The protrusion lengths fll, ft2, 113 are selected to be 5 μm or more, preferably 10 μm or more. Projection length Jll, J22, j
23 is smaller than 5 μm, overhang 91,
The influence of the shadow effect of 101 begins to appear, and cracks are more likely to occur.

If the edge B of the lead conductors 7 and 8 protrudes from the edge A of the extraction electrodes 9 and 10 by 5 μm or more, the lead conductor 7,
The edge portions of the electrodes 8 that protrude by 5 μm or more are not affected by the shadow effect caused by the overhang portions 91 and 101 of the extraction electrodes 9 and 10 when the protective film 11 is sputtered. Therefore, the step covering between the lead conductors 7, 8 and the extraction electrodes 9, 10 is improved, and as shown in FIG. 4(a), cracks do not occur in the protection film 11. Therefore, as shown in FIG. 4(b), by polishing the surface of the IIA film 11 and exposing the extraction electrodes 9 and 10, a crack-free thin film magnetic head can be obtained.

The vertical distance d of the cavities 92, 102 formed between the overhangs 91, 101 and the surfaces of the lead conductors 7, 8 is set to 1/10 or less of the height d2 of the extraction electrodes 9, 10. This further improves the step coverage described above.

Effects of the Invention> As described above, the present invention provides a thin film magnetic head element,
A lead conductor electrically connected to the conductor coil film of the thin-film magnetic head element, an extraction electrode formed on the lead conductor, a protective film covering the entire extraction electrode except for an external conductor connection surface, and a substrate supporting the whole. A thin film magnetic head having:
Since the leading edge of the lead conductor protrudes beyond the edge of the lead-out electrode by 5 μm or more, a thin-film magnetic head without cracks in the protective film around the lead-out electrode can be provided.

[Brief explanation of the drawing]

FIG. 1 is a perspective view of the main parts of a thin film magnetic head according to the present invention;
Figure 2 is an enlarged sectional view taken along the major axis direction X of the extraction electrode in Figure 1, Figure 3 is an enlarged sectional view taken along the minor axis direction Y of the extraction electrode in Figure 1, and Figure 4 (a ). (b
) is a sectional view showing protective film sputtering, FIG. 5 is a perspective view of the main part of a conventional thin film magnetic head, FIG. 6 is a sectional view of the main part, and FIG. 7 is an enlarged sectional view of the extraction electrode part. FIGS. 8(a) to 8(d) are diagrams showing a conventional method for forming an extraction electrode. 1... Substrate 2, 4... Magnetic film 5... Conductor coil film 6, 61-63... Absolute Mlli 7, 8... Lead conductor 9, IO... Extracting electrode 11...・Protective film-2J

Claims (3)

[Claims] (1) A thin film magnetic head element having a magnetic circuit including a magnetic film and a conductor coil film, a lead conductor electrically connected to the conductor coil film, an extraction electrode formed on the lead conductor, and an external conductor connection of the extraction electrode. A thin film magnetic head having a protective film covering the entire surface except for a surface, and a substrate supporting the whole, characterized in that the edge of the lead conductor protrudes from the edge of the extraction electrode by 5 μm or more. Thin film magnetic head. (2) The extraction electrode has an overhang portion that creates a cavity between it and the surface of the lead conductor, and the edge of the lead conductor protrudes from the edge of the overhang portion by 5 μm or more. 2. A thin film magnetic head according to claim 1, characterized in that: (3) In the hollow portion, the distance between the overhang portion and the surface of the lead conductor is 1/1 of the height of the extraction electrode.
3. The thin film magnetic head according to claim 2, wherein the magnetic field is 0 or less.