JPH1083525A - Thin film magnetic head and wafer for thin film magnetic head - Google Patents

Abstract

PROBLEM TO BE SOLVED: To shorten measuring time without increasing number of probe pins in measurement of electric characteristics of a thin film magnetic head on a wafer for a thin film magnetic head by providing terminals for connecting with a magnetic disk device on at least two surfaces of a head slider element surface and a slider rear surface. SOLUTION: The terminals 15 for connecting with the magnetic disk device are formed on at least two surfaces of the element surface 12 side of the thin film magnetic head 11 and a surface 14 opposite to a magnetic recording medium facing surface 13. Further, pulling terminals having less number of terminals are provided from connecting terminals of element surface sides of respective heads on the wafer for the thin film magnetic head. For example, when (n) pieces of composite heads having four pulling terminals on one head are arranged in a row on the wafer, number of pulling terminals in a row is 4n. Number of pulling terminals is reduced to 2n+1 by prescribed connections and thereby number of shifting at the time of measuring can be reduced.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a thin-film magnetic head, and more particularly, to a process for inspecting a wafer on which a thin-film magnetic head is mounted at high density and a wafer for the thin-film magnetic head suitable for the inspection process.

[0002]

2. Description of the Related Art As described in Japanese Patent Application Laid-Open No. 07-176002, the terminals of a conventional thin-film magnetic head can save soldering space as a magnetic disk drive and restrict the space for mounting lead wires to a head slider. Describes a method for reducing the number of lead terminals from the thin-film magnetic head. That is, the number of terminals of the thin-film magnetic head itself is reduced by one compared with the conventional element.

However, when the number of thin-film magnetic heads is increased on a wafer and data such as the resistance of an element is measured, reduction of the measurement time without increasing the number of probe pins is not considered. .

No consideration is given to reducing the manufacturing time and cost of the wafer by collecting the lead terminals in a part of the wafer.

[0005]

In a magnetic disk drive for recording and reproducing information using a disk-shaped magnetic recording medium, a magneto-resistive head having excellent reproduction sensitivity has been developed as the density of information on the recording medium increases. It is being used. This magnetoresistive head is a head using an MR element whose electric resistance changes in response to a change in an external magnetic field, and is used only for reproduction. Therefore, in general, decoding is performed in combination with an inductive recording head. Used as a head. When one inductive head is used for both recording and reproduction, the number of lead-out terminals is two. Compared with such an inductive recording / reproducing head, the composite head unit has four lead terminals, two for the recording head and two for the reproducing head. In recent years, thin-film magnetic heads have rapidly become thinner and smaller with the increase in the size and capacity of magnetic disk drives.
Therefore, the number of heads per wafer in the manufacturing process is rapidly increasing. In addition, since the composite head unit has twice as many lead terminals as the induction type recording / reproducing head as described above, the number of lead terminals per wafer is greatly increased. If there are 15,000 composite head units per wafer, the number of extraction terminals is 60,000. When measuring the electrical characteristics of this device, it takes about 0.8 seconds to move the probe pins per device, and about 12000 seconds (3.3 hours) for one wafer. The longer the measurement, the higher the cost. To reduce the cost, it is necessary to reduce the measurement time, and to reduce the measurement time, it is effective to reduce the number of times the probe pins move. As a method of reducing the number of movements of the probe pins, a method of increasing the number of probe pins can be considered. However, even if one of the probe pins is lost, the measurement becomes impossible. In addition, when the number of probe pins increases, it becomes difficult to maintain the probe pins for bending.

Accordingly, a first object of the present invention is to measure the electrical characteristics of a thin-film magnetic head on a wafer for a thin-film magnetic head by reducing the measurement time without increasing the number of probe pins. An object of the present invention is to provide a head and a wafer for a thin-film magnetic head.

A second object of the present invention is to provide a thin-film magnetic head and a wafer for a thin-film magnetic head which enable terminal arrangement to reduce costs in a wafer manufacturing process.

[0008]

The above object is achieved by a thin-film magnetic head having a connection terminal for connecting to a magnetic disk drive on at least two surfaces of an element surface of a head slider and a back surface of the slider.

In the thin-film magnetic head, data such as electric resistance of at least two or more thin-film magnetic head elements is stored in 2 × (m−1) + (n−1) terminals (however, The number of terminals is m and the number of terminals per head is n.), And the terminals for measurement are collected on a part of the wafer.

Further, when measuring the resistance or the like of an element in a thin-film magnetic head, a measuring probe (probe pin) is used.
This is achieved by measuring data of at least two or more elements by electrical means without moving the position of.

Next, the operation principle of the present invention will be described with reference to FIG. FIG. 5 is a schematic view of an arrangement in which four thin film magnetic head elements are arranged. First, the left terminal of the IND head of the first head and the left terminal of the MR head are connected to newly provide a terminal 1 for measurement, and then the right terminal of the MR head of the first head is provided as a terminal 2 for measurement. , The right terminal of the IND head of the first head, the IND head of the second head, and the MR
The terminal 3 for measurement is newly formed by connecting the left terminals of the head. Thereafter, new measurement terminals 1 to 9 are sequentially formed up to the fourth head. With this connection, for example, when measuring the resistance of the IND head of the first head, if the measurement is performed between the measurement terminals 1-3, the other connected heads are not measured. When measuring the MR head of the first head, the measurement may be performed between the measurement terminals 1-2. Sequentially between measuring terminals 3-5, 3-4
By measuring the interval, 5-7, 5-6, 7-9, and 7-8, the measurement can be performed without receiving interference from other heads. In addition, with this configuration, the inspection apparatus is conventionally moved for each element, but can be reduced to about １ ／.
The time can be reduced to 1.6 hours.

Further, if a thin film magnetic head wafer is manufactured by limiting the number of terminals for measurement to one or several, the moving distance of the measuring device can be reduced, and the measuring time can be further reduced. In addition, this makes it possible to reduce the thickness of the protective film for protecting the element, thereby reducing the manufacturing cost. In a conventional wafer for a thin film magnetic head, terminals for measurement are uniformly arranged on the entire surface of the wafer. The thin film magnetic head wafer is warped due to stress when forming the protective film. Therefore, in order to maintain the accuracy of the wrap (height in the wafer thickness direction) in the final step between the terminal in the center portion of the wafer and the terminal in the wafer terminal portion, the protective film must be thickened accordingly. It takes a lot of time to form a protective film. Therefore, if a wafer for a thin film magnetic head is manufactured by limiting the number of measurement terminals to one or several places on the wafer,
It is possible to make the protective film thinner and shorten the film forming time.

[0013]

1 and 2 show a thin-film magnetic head and a wafer for a thin-film magnetic head as an embodiment of the present invention.
This will be described below. As shown in FIG.
Surface 1 opposite to element surface 12 side and magnetic recording medium opposing surface 13
4 has a connection terminal 1 for connecting to a magnetic disk drive.
5 are formed, and as shown in FIG. 2, lead terminals 22 are further provided on the wafer from the lead terminals 21 on the element surface side of each head. Taking a composite head having an inductive recording head and a magnetoresistive reproducing head as an example, one head has four lead-out terminals, and if n heads are arranged in one row on a wafer, one head has The number of lead terminals is (4n). As shown in FIG. 2, according to the present invention, the number of lead-out terminals per row can be reduced to (2n + 1), which is almost halved compared to the related art.

Here, a method for manufacturing a terminal according to the present invention will be described with reference to FIG. A lead wire is led to the terminal forming portion from the tip of the element. A resist is formed on this upper portion, and Cu plating corresponding to the terminal is performed. After that, the resist is removed to expose Cu. Next, an alumina film for protecting the element is formed, and the surface is wrapped to expose the Cu terminal surface. Thereafter, the resist is patterned, and Au is patterned.
Plating is performed, and finally the resist is removed to form terminals.

Next, a measuring apparatus and a measuring method will be described with reference to FIGS. The measuring apparatus mainly includes a stage 31 on which a wafer is placed, a controller 32 for controlling the movement of the stage, a probe pin 32, a resistance measuring section 34, and a probe pin 33 for switching a probe pin 33 connected to the resistance measuring section 34. And a switch 35 between the resistance measuring unit 34 and the resistance measuring unit 34. The measuring method is such that the stage 31 on which the wafer is mounted moves to bring the probe pins 33 into contact with the lead terminals 22, and the resistance is measured after the contact resistance between the lead terminals 22 and the probe pins is stabilized. At this time, the probe pin 33 connected to the resistance measuring unit 34 is switched by the switch 35, and a plurality of elements are measured each time the stage moves once. This series of operations is repeated to measure the resistance of the recording head and the reproducing head.

FIG. 6 shows an example in which the number of lead-out terminals can be further reduced as compared with the above-mentioned example by three-dimensionally intersecting the wiring from the element to the lead-out terminal. FIG. 6 is a schematic view of an arrangement of five thin film magnetic head elements, in which the number of terminals for measurement is five. The left terminal of the IND head of the first head, the left terminal of the MR head, the left terminal of the IND head of the second head, and the left terminal of the MR head are connected to form a new measurement terminal 1.
Next, the right terminal of the MR head of the first head, the left terminal of the IND head of the third head, the left terminal of the MR head, and the left terminal of the IND head of the fourth head are connected to each other, and a measurement terminal 2 is connected. To form Further, the first head IN
The terminal 3 for measurement is formed by connecting the right terminal of the D head, the right terminal of the MR head of the third head, and the left terminal of the MR head of the fourth head. Hereinafter, measurement terminals 1 to 5 are sequentially formed up to the fifth head. In this connection, for example, when measuring the resistance of the IND head of the first head, if the measurement is performed between the measurement terminals 1-3, the other connected heads are not measured. When measuring the MR head of the first head, the measurement may be performed between the measurement terminals 1-2. Measurement terminal 1 sequentially
-5, 1-4, 2-4, 2-3, 2-5, 3
By measuring between -4, 3-5, and 4-5, it is possible to measure without interference from other heads.

In this case, the number of lead terminals is one.
/ 4. Also, by arranging the stage at a part on the wafer, the number of times the stage is moved is halved, and the moving distance is reduced. Measurement time can be greatly reduced.

[0018]

According to the present invention, the time for measuring each electrical characteristic can be shortened, the manufacturing cost can be reduced, and the mass production efficiency can be improved.

[Brief description of the drawings]

FIG. 1 is a schematic view of a thin-film magnetic head according to an embodiment of the present invention.

FIG. 2 is a schematic diagram of a terminal arrangement pattern on a wafer according to one embodiment of the present invention.

FIG. 3 shows an embodiment of the present invention.

FIG. 4 shows a schematic diagram of a terminal formation process.

FIG. 5 is a schematic diagram showing the operation principle of one embodiment of the present invention.

FIG. 6 is a schematic diagram showing the operation principle of one embodiment of the present invention.

[Explanation of symbols]

11: Thin-film magnetic head, 12: Element surface, 13: Surface facing magnetic recording medium, 14: Thin-film magnetic head support, 15
... Connection end, 21 ... Drawer terminal, 22 ... Drawer terminal,
31: stage, 32: controller, 33: probe pin, 34: resistance measuring unit, 35: switch.

Claims (4)

[Claims] 1. A thin-film magnetic head having connection terminals for connecting to a magnetic disk drive on at least two surfaces of a thin-film magnetic head slider, a back surface (slider back surface) with respect to an element surface and a medium facing surface. 2. In the thin film magnetic head, data such as electric resistance of at least two or more thin film magnetic head elements is stored in 2 × (m−1) + (n−1) terminals (however, Wherein the number is m and the number of terminals per head is n.) 3. The thin-film magnetic head wafer according to claim 1, wherein terminals for measurement are collected on a part of the wafer. 4. In a thin-film magnetic head, when measuring resistance or the like of an element, data of at least two or more elements can be measured by electrical means without moving the position of a measuring probe (probe pin). Inspection method for a thin film magnetic head wafer.