JPS5931127B2 - Multi-element magnetic head - Google Patents

Description

[Detailed Description of the Invention] As magnetic disk devices, magnetic drum devices, etc. used in external storage devices for computers move toward larger capacities, faster speeds, and lower prices, the magnetic heads used in these devices also become denser. , and are moving in the direction of lower prices.

Therefore, a multi-element magnetic head that applies thin film integration techniques such as plating vapor deposition and etching has recently been announced, and several shapes have been proposed and are now publicly known. These integrated magnetic heads can form a large number of magnetic head elements at once on the end face of the floating slider of the magnetic head, and do not require manual work such as winding. It is possible to supply a stable, low-cost, high-density magnetic head with little characteristic deviation. The method of transmitting and receiving signals between these magnetic head elements and external recording and reproducing circuits is as follows:
There is a method of taking out the lead wires by soldering them one by one to the connection terminals on the floating slider of the multi-element magnetic head or by ultrasonic bonding. However, since it is usually necessary to take out 2 to 3 lead wires per element, when the number of elements increases from 9 to 40, the number of lead wires becomes extremely large, approximately 20 to 120, and the number of man-hours required for connection at the connection terminal section. Therefore, it is extremely difficult to connect the connected lead wires to a predetermined circuit terminal without tangles, and there are many disconnections during handling. Therefore, conductive foil such as copper is pasted on a flexible insulating film such as polyimide, polyamide, or Teflon, and a pattern is formed by etching to obtain the required number of lead wires. An infrared connection method has been proposed in which an infrared light source is moved relative to each other at the connection terminal portion and the circuit connection portion of the circuit to heat and solder them all at once. This method allows a large number of connections to be made stably in a short period of time. Incidentally, since the connecting terminal portion and the multi-element magnetic head portion are generally formed by plating, vapor deposition, etching, etc., they are formed on the same plane due to the manufacturing process. This plane is usually used with a slider end surface that is approximately perpendicular to the slider floating surface, so that the flexible conductor is connected in a direction parallel to this end surface. To connect this flexible conductor to a circuit terminal located parallel to the floating slider, it is necessary to bend the flexible conductor approximately 900 degrees at an appropriate position between the connecting terminal portion and the circuit terminal portion. In such cases, repetitive stress is applied to the bending part during the following motion of the floating slider, resulting in fatigue breakage, or a moment is generated at the connection between the floating slider and the flexible conductor, causing a large shift in the slider attitude angle.
It may cause you to become unable to float. Therefore, in order to obtain a reliable magnetic head structure with stable floating performance, the slider must be flexible in a direction approximately perpendicular to the end surface where the magnetic head element is formed and parallel to the slider floating surface. It is necessary to create a three-dimensional connection structure in which conductors are connected. If such a three-dimensional connection structure becomes possible, in addition to the above-mentioned advantages in terms of floating performance, a second advantage is that it will become easier to realize a lightweight floating slider suitable for micro-floating gap sliders. be. That is, the floating void is 0.4μ to 1μ
A slider that floats in an extremely small gap, such as the slider, must have a light load to prevent head sliding damage, and therefore must be light in weight, and therefore the thickness of the slider must be as thin as possible. As a result, there is no room for forming a connection terminal on the end surface where the magnetic head element is formed, and by providing a connection terminal on the back surface of the slider through a three-dimensional connection structure, it is easy to connect the micro-floating gap slider to an external circuit. Become. The third difference is that in order to process the weak signal output of the thin film magnetic head,
It is desirable to mount a pulse transformer or an IC chip such as a reproduction preamplifier very close to the magnetic head, but if such a three-dimensional structure is used, the pulse transformer or IC chip can be easily mounted on the back of the slider. , to be able to connect. Regarding the three-dimensional connection structure of such a thin film magnetic head, the US
An example is proposed in No. P36578O6.

However, in this method, since the structure is such that they are connected to each other by drilling holes in the two planes of the slider block and burying the conductor, the pitch of the connection terminals is fine, such as 0.5 mm or less, and the pitch is 20 to 120 mm. When a large number of connections are made to a book, it is difficult to put it into practical use due to limitations in drilling precision and manufacturing costs. The present invention provides a three-dimensional connection structure for such a thin film magnetic head that is low cost and easy to manufacture.

This will be explained in detail below using figures.

FIGS. 1 and 2 show typical examples of the structure of conventional thin film magnetic heads. The magnetic head is formed on the end surface 2 of the floating slider 1, and information is recorded and reproduced by relative movement of the recording medium surface 3 in the direction U in FIG. The floating slider is supported and fixed to the head support plate 6 by a support spring 5 consisting of a gimbal spring or a load spring, and a floating gap determined by the load applied from the support spring and the equilibrium point of the floating blade of the slider is provided. Also, the support spring ensures followability to the surface of the recording medium. FIG. 2 is an enlarged view of the end face 2 forming the magnetic head. In an example in which the floating slider is made of ferrite material, the conductor 7 and the connecting terminal 9 are formed on the ferrite material, and the magnetic body 8 is formed on this conductor. In this case, it is clear that T is the track width and the thickness of the conductor 7 is the magnetic head gap length.
Now, let us consider connecting the connection terminal of such a floating slider and an external circuit terminal through the flexible conductor 4. For example, the flexible conductor has a thickness of 0.02 to 0.111t7! A conduit foil 11 with a thickness of 0.02 to 0.1 mm is formed on a flexible insulating film 10 of 1 mm, and as shown in FIG. Since it has to be pulled out, a bent part 12 must be provided, which may cause fatigue disconnection at this part as described above, or pitching which causes a negative angle of attack with respect to the movement of the magnetic disk of the floating slider due to moment action. If the rigidity in the rolling direction is increased, floating instability may occur, resulting in a serious problem in terms of reliability. If a structure in which the flexible conductor is connected in a direction substantially perpendicular to the end surface on which the magnetic head element is formed and substantially parallel to the slider floating surface can be realized, the bent portion 12 can be eliminated. A first example of a method for realizing this is to connect one end surface 2 and the other end surface 13 of the floating slider using a manufacturing process applying thin film integration technology, as shown in FIG. This is a method of connecting flexible conductors. Considering the practical process of such a structure, it is generally difficult to form conductors on the two surfaces 2 and 13 at the same time due to technical limitations such as photoresist coating, pattern formation, vapor deposition, plating, and etching. Therefore, after forming one side first,
This surface may be masked with a suitable masking material such as photoresist to form the second surface. A second example of the three-dimensional connection method is to form a pattern as shown in FIG. 4 in advance in the vicinity of the ridges 14 of the end surfaces 2, 13 of the floating slider before forming the magnetic head element by a technique such as screen printing. This is the way to keep it.

That is, a conductive paste such as tungsten or molybdenum-manganese is applied to the conductor Al5 on the end face 2 and the conductor Bl6 on the end face 13.
It is screen printed through a screen formed into the shape required for the part to be formed, and then fired at a high temperature. On the conductors A and B thus formed, a metal with good solderability and strong adhesion, such as a combination of nickel chrome and gold, is adhered by plating or other methods, and then a magnetic head element is formed on the end face 2. Then, a structure equivalent to that shown in FIG. 3 can be obtained. Incidentally, the conductors 15 and 16 formed in this way
If it is invaded by the chemical process in forming the magnetic head element, it must be masked by an appropriate method during the element forming process, and after the process is completed, the gap between the conductor Al5 and the element conductor 7 is removed by melting solder, etc. Bridge connection is required. However, when the surfaces of the conductors Al5 and Bl6 are covered with chemically stable gold, the conductors Al5 and Bl6 can be etched by selecting a material that can be selectively etched, such as aluminum, copper, or silver, for the conductor 7 in the magnetic head element part.
There is no need for masking, and the conductor 7 can be formed directly on the conductor Al5, which facilitates manufacturing. In the second example of the above three-dimensional connection method, the deviation from conductor A (!:B) is, for example, 0.2 m7! due to constraints on screen printing accuracy.
Since there is also l, the spacing conductor pitch is, for example, 0.511t11.
As the size becomes smaller, it becomes difficult to realize.

FIG. 5 shows an example of a third three-dimensional connection method suitable for cases where the conductor pitch is small. In this case, the screen-printed pattern has a continuous strip shape as shown by solid lines 15' and 16'. After electrical continuity is established between the conductor 7 and the conductors 15' and 16' of the magnetic head element through the same process as shown in FIG. A three-dimensional connection structure equivalent to that shown in FIG. 3 is obtained. In this example, unlike the second example, the deviation between conductors A (5B) can be ignored, and the processing accuracy can be increased to 0.011t711, so a conductor pitch structure with a pitch of about 0.1mm can be used. It can be easily formed.Such groove processing can be done by stacking thin cutters at the required pitch for the number of grooves required for cutting.
It can be processed simultaneously and can be easily formed in an extremely short time.
Although the three examples given here illustrate three-dimensional connections between planes that are substantially orthogonal to each other, it is clear that three-dimensional connections between two planes having arbitrary intersection angles can be made using exactly the same method. Further, a chamfer or a small radius which can be ignored in terms of pattern formation accuracy may be provided on the ridge line portions at arbitrary intersection angles. FIG. 6 is a structural diagram of a magnetic head according to the present invention. 1...Floating slider, 2...Magnetic head forming end surface, 3...
...Recording medium surface, 4...Flexible conductor, 5...
...Support spring, 6...Head support plate, 7...
...Conductor, 8...Magnetic material, 9,9'...
...Connection terminal, 10...Flexible insulating film, 13...Slider back, 14...
Slider crest, 15, 1rJ...Conductor A, 1
6, 16'...Conductor B, 17...Groove portion, 18...Conductor connection portion.

Claims (1)

[Claims] 1. In a multi-element magnetic head, the end surface on which the magnetic head elements are formed approximately perpendicular to the floating surface of the floating slider is defined as a first plane, and the back surface of the slider that intersects with this plane and is approximately parallel to the floating surface is defined as a second plane. a plane, and the first plane and the second plane are adjacent to each other at the ridge line portions of these planes,
A conductor is formed so as to obtain electrical continuity, and flexible conductors arranged along this plane are connected on the second plane so that the conductors overlap each other at the connection part. Multi-element magnetic head.