JPH0489609A - Thin-film magnetic head - Google Patents

Abstract

PURPOSE:To prevent the oxidation of the surfaces of Cu electrode pads in stages up to bonding by forming layers consisting of Ni, Co or an alloy essentially consisting of thereof on the surfaces of Cu electrode pads. CONSTITUTION:Contact holes are formed in an insulating layer 10 and the inside of the contact holes is filled with conductors 13. A Cu layer having 0.1 to 10mum thickness connecting to coil conductors 7 is formed via the conductors 13. This Cu layer is etched to prescribed shapes to form lead parts 14 and pad parts 15. A protective film is formed and the layers 16 consisting of the Ni, Co, Pb or the alloy essentially consisting thereof, for example, PbSn, are formed at 5 to 30mum thickness, after cutting to chips. Lead wires 17 are then thermocompression bonded. The layers consisting of the Ni, Co or the alloy essentially consisting thereof are formed on the surfaces of the Cu recording pads of the thin-film magnetic head in such a manner, by which the formation of oxide films on the surfaces of the Cu electrode pads in the stages up to bonding is prevented.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a thin film magnetic head in which electrode pads are made of Cu (copper).

(Prior Art) Pads for connecting to lead wires of thin-film magnetic heads have conventionally been made of Cu, which has high conductivity. However, when the electrode pad is made of Cu, an oxide film is formed on the surface of the Cu, so it is necessary to polish the surface before connecting the lead wire.

Therefore, Japanese Patent Application Laid-open No. 1-199310 proposes to prevent the formation of an oxide layer by forming a Ti or Cr layer on the surface of a Cu electrode pad.

(Problem to be Solved by the Invention) By the way, the electrode pad and the lead wire are bonded by thermocompression bonding or soldering, which is disclosed in the above-mentioned Japanese Patent Application Laid-Open No. 1-1999.
When a Ti or Cr layer is formed on the surface of an electrode pad as in No. 310, a strong oxide layer is formed on the surface of the Ti or Cr layer, making it difficult to bond the electrode pad and lead wire using normal methods. I can't do it.

Furthermore, when the number of wires is large, such as in a multi-track, a flexible wire 100 with a Cu lead pattern 102 formed on the surface of a heat-resistant resin 101 such as polyimide resin is used, as shown in FIG. However, the heat resistant resin 101 has a heat resistance temperature of approximately 200°C. For this reason, C
If a Ti or Cr layer with a high melting point is formed on the second layer of the U layer, the flexible wire 100 cannot be thermocompression bonded directly to the pad 103 of the thin film head, and these are connected with a thin wire 104 of A1 or Au. ing. Therefore, a process such as ultrasonic bonding is required.

(Means for Solving the Problems) In order to solve the above problems, the first invention of the present application forms a NiXCo or an alloy layer containing these as main components on the surface of the Cu electrode pad of a thin film magnetic head, and the second invention , a low melting point alloy layer such as Pb or Pb5n was formed on the surface of a Cu electrode pad of a thin film magnetic head.

(Function) A magnetic core and a coil conductor are laminated on a substrate via an insulating film, a Cu layer is formed on this coil conductor via an insulating layer, and Ni, Co, etc. are formed on this Cu layer. This prevents the surface of the Cu electrode pad from being oxidized in the process up to bonding, and also prevents the surface of the Cu electrode pad from being coated with Pb or Pb.
By forming a low melting point alloy layer such as b5n, the thermocompression bonding temperature can be lowered.

(Example) Embodiments of the present invention will be described below with reference to the accompanying drawings.

FIG. 1 is a perspective view showing the essential parts of the thin film magnetic head according to the present invention, FIG. 2 is a plan view of the same thin film magnetic head, and FIG.
FIGS. 3(a) to 3(j) are diagrams showing the manufacturing method of the thin film magnetic head described in 2. In this embodiment, all the magnetic cores are buried in an insulating film to ensure the flatness of each layer. Indicates a product that has been processed with high precision.

That is, as shown in FIG. 3(a), the thin film magnetic head is manufactured using a thin film forming technique (sputtering, vapor deposition, CVD) on a substrate 1.
, plating, etc.) to form an insulating layer 2 of SiO2, T 102 or A 120 a with a thickness of 1 to 10 μm, and then the insulating layer 2 is etched through a mask made by photolithography to form the core. A shaped groove 3 is formed. Then, as shown in the same figure (b), the groove 3
A layer of soft magnetic abrasive mainly composed of Fe, Co, and Ni is formed inside the magnetic layer using thin film formation technology, and the excess portion of the upper part of this magnetic layer is removed by polishing to flatten the surface and form the lower core 4. do.

Next, as shown in the same figure (C), another insulating layer 5 is formed on the insulating layer 2, and as shown in the same figure (d), the coil groove 6 formed on the surface of the insulating layer 5 by etching is A conductor such as Cu, Al, Au, or Ag is embedded using a thin film forming technique, and the excess portion on the conductor is removed by polishing to flatten the surface to form the coil conductor 7. Note that the depth of the coil groove 6 does not reach the lower core 4 to ensure electrical insulation.

Thereafter, as shown in FIG.
．． It is formed to have a thickness of 1 to 1 μm, and grooves 8a and 8b of the intermediate core are formed at the front and rear by etching, as shown in FIG. 2(f). At this point, the cutting and sawching are stopped for the front intermediate core groove 8a, leaving a gear gap, and for the rear groove 8b, the machining and sawching are continued until the lower core 4 is exposed.

Next, as shown in the same figure (g), grooves 8a, 8 of the intermediate core
A layer of a soft magnetic material mainly composed of Fe, Co, and Ni is formed using thin film formation technology within b, and the excess portion of the upper part of this magnetic layer is removed by polishing to flatten the surface and form the intermediate core 9. do.

As shown in the same figure (h), an insulating layer 10 of 8102, TiO2, A1°03, etc. is formed using thin film forming technology.
is formed with a thickness of 1 to 10 μm, and the core groove 1 is formed in the same manner as above.
1, a layer of soft magnetic material mainly composed of Fe, Co, and Ni is formed in the groove 11 as shown in FIG. The upper core 12 is obtained by removing the upper core 12 and flattening the surface.

After that, a contact hole is formed in the insulating layer 10, and a conductor 13 is inserted into the contact hole as shown in FIG.
A Cu layer with a thickness of 0.1 to 10 μm is formed and connected to the coil conductor 7 via the conductor 13. This Cu layer is etched into a predetermined shape to form the lead portion 14 and the pad portion 15.
shall be. After forming a protective film and cutting chips, a layer 16 of Ni, Co, Pb, or an alloy layer 16 mainly composed of these, for example, Pb5n, is applied to the surface of the pad portion 15 to form a layer of 5 to 3
It is formed to have a thickness of 0 μm, and the lead wire 17 is bonded by thermocompression.

FIGS. 4(a) to 4(f) are diagrams showing another method of manufacturing a thin film magnetic head according to the present invention.

That is, as shown in FIG. 4(a), the thin film magnetic head has a lower core 22 made of a soft magnetic material mainly composed of Fe, Co, and Ni, formed on a substrate 21 by thin film forming technology, and a lower core 22 made of a soft magnetic material mainly composed of Fe, Co, and Ni. As shown in the same figure (b), resin, 5102, T i
A gap layer 23 and an insulating layer 24 are formed using O2 or A103, and then Cu is formed on the insulating layer 24 using a thin film formation technique.

A coil conductor 25 of Δl, Au, Ag, etc. is formed, and then the coil conductor 25 is made of SiO as shown in FIG.
2. Cover with an insulating layer 26 such as TiO2 or Al2O3 and form an upper core 27 made of a soft magnetic abrasive material mainly composed of Fe, Co, and Ni, and then as shown in FIG. forming a contact hole 28 in the insulating layer 26;
Next, as shown in FIG. 5F, a Cu layer 29 is formed to be connected to the coil conductor 25 through a contact hole 28, and a layer 30 of N1, C01Pb, or an alloy containing these as main components is formed on the surface of this Cu layer 29. is formed and etched into a predetermined shape to form a lead portion and a pad portion.

(Effects) As explained in Section 2, according to the present invention, since NiXCo or an alloy layer containing NiXCo as a main component is formed on the surface of the Cu electrode pad of the thin-film magnetic head, the Cu electrode pad is removed in the process up to bonding. It can prevent the formation of an oxide film on the surface.

On the other hand, by forming a low melting point alloy layer such as Pb or Pb5n on the surface of the Cu electrode pad, the electrode pad and the lead wire can be bonded at a low temperature of 200°C or less, so that It does not destroy the insulating layer.

In addition, since thermocompression bonding can be performed at low temperatures, even when there are a large number of lead wires such as a multi-track system as shown in FIG. The flexible wire 100 can be thermocompression bonded to the pad 103 of the head.

[Brief explanation of the drawing]

FIG. 1 is a perspective view showing the essential parts of the thin film magnetic head according to the present invention, FIG. 2 is a plan view of the same thin film magnetic head, and FIGS. 3 (a) to (j) are the thin film magnetic head. 4(a) to (f) are diagrams showing other examples of the manufacturing method of a thin film magnetic head, and FIG. 5 is a diagram showing a pad and flexible wire of the thin film magnetic head according to the present invention. FIG. 6 is a diagram showing the connection state between the pad and flexible wire of a conventional thin film magnetic head. DESCRIPTION OF SYMBOLS 1... Substrate, 2.5... Insulating layer, 4... Lower core, 7... Coil conductor, 12..." Lower core,
15...Pad part, 16...Ni, Co,...P
b or an alloy layer containing these as main components, 17... lead wire. C) faction

Claims (2)

[Claims] (1) In a thin film magnetic head in which a magnetic core and a coil conductor are laminated on a substrate via an insulating film and a Cu electrode pad is connected to the coil conductor, the surface of the Cu electrode pad is coated with Ni, Co or A thin film magnetic head characterized by forming an alloy layer containing these as main components. (2) In a thin film magnetic head in which a magnetic core and a coil conductor are laminated on a substrate with an insulating film interposed therebetween, and a Cu electrode pad is connected to the coil conductor, the surface of the Cu electrode pad is coated with Pb or Pb. A thin film magnetic head characterized by forming a layer of a low melting point alloy as a main component.