JPH056512A - Production of thin-film magnetic head - Google Patents

Abstract

PURPOSE:TO prevent the generation of warpage in a wafer and to substantially prevent the generation of the mis-registration of alignment by forming film parting grooves around respective chips during the process for forming thin films on the wafer. CONSTITUTION:A film consisting of Al2O3 is formed on one surface of the wafer 12 which is a substrate consisting of plastic. A lower magnetic layer, coil conductor, insulating layer, upper magnetic layer, etc., are laminated thereon by a thin film forming method using sputtering, etc., to form plural chips 16, 16,... having electromagnetic conversion elements 14 and bonding pads 20, etc., in an arraying state. The warpage is generated gradually in the wafer 12 by the film stresses, etc., on continuation of the formation of these thin films but the film stresses in the transverse direction of the wafer 12 are relieved by the film parting grooves 18 formed around the respective chips 16, 16..., by which the wafer 12 is flattened. Then, the generation of the unequal coating of a resist, etc., and the mis-registration at the time of alignment is substantially prevented and the thin-film magnetic head having high accuracy is produced.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of manufacturing a thin film magnetic head used in a magnetic disk device or the like.

[0002]

2. Description of the Related Art A thin film magnetic head is generally constructed by forming an electromagnetic conversion element having a coil conductor and a magnetic gap on a slider having a flying rail.

Generally, the process of manufacturing the thin film magnetic head can be roughly divided into a thin film forming process and a slicing / polishing process.

In the thin film forming process, a wafer 10 made of AlTiC whose surface is coated with Al ₂ O ₃ or the like as shown in FIG. 3A is used, and a large number of electromagnetic conversion elements and bonding pads are formed on one surface of the wafer 10. Are laminated by a thin film forming method to form a plurality of chips.

After that, in a slicing / polishing step, each chip is cut out from the wafer 10, and each cut-out chip is processed by polishing or the like to be processed into a slider having a flying rail to manufacture a thin film magnetic head.

[0006]

In the thin film forming process in the above manufacturing process, when a film is formed on the wafer 10, a film is formed on the wafer 10 by sputtering or vapor deposition plating, but heat or film stress at that time is applied. By wafer 10
In addition, a warp as shown in FIG.

The warp of the wafer 10 causes coating unevenness in resist coating, positional deviation during alignment such as mask alignment, and track width deviation, which is a major obstacle to the manufacture of a thin film magnetic head that requires high accuracy. It was a thing.

Due to the demand for thin, thin and compact thin-film magnetic heads, mass production, and rationalization, the current wafer size is generally about 3 inches in diameter and about 4 mm in thickness.
It is expected that the size of wafers in the future will increase to about 4 to 6.0 inches in diameter and thinner to about 2.8 to 2 mm, and it is inevitable that the problem of wafer warpage will be highlighted. Is.

The present invention has been made to solve the above problems, and provides a method of manufacturing a thin film magnetic head in which the wafer is not warped during the manufacturing process of the thin film magnetic head.

[0010]

A method of manufacturing a thin film magnetic head according to claim 1 is a method of forming a thin film on an electromagnetic conversion element having a lower magnetic layer, a coil conductor, an insulating layer, an upper magnetic layer, etc. on one surface of a wafer. In a method of manufacturing a thin film magnetic head by stacking and forming a plurality of chips in an aligned state and cutting them out and processing them into a slider shape, a film dividing groove is formed around each chip during a process of forming a thin film on a wafer. It is characterized by forming.

According to a second aspect of the present invention, there is provided a thin film magnetic head manufacturing method, wherein an electromagnetic conversion element having a lower magnetic layer, a coil conductor, an insulating layer, an upper magnetic layer and the like is laminated on one surface of a wafer by a thin film forming method to form a plurality of chips. In the method of manufacturing a thin film magnetic head by forming these in an aligned state and cutting them and processing them into a slider shape, a film dividing groove is formed around a block composed of a plurality of chips during the process of forming a thin film on a wafer. It is characterized by doing.

[0012]

According to the present invention, a warp that occurs when a thin film magnetic head is manufactured by laminating an insulating layer, a magnetic layer, a coil conductor and the like on a wafer by forming a thin film, forms a film dividing groove on the wafer to remove film stress. Flatten the wafer.

The film dividing grooves are formed around each chip or around a block composed of a plurality of chips so as not to damage the chips formed on the wafer.

At this time, it is necessary that the film dividing groove does not adversely affect the electromagnetic conversion element formed of an insulating layer, a magnetic layer, a coil conductor, etc. formed on the wafer, and the width of the film dividing groove is 5 μm or more. It is preferably about 0.4 mm.

[0015]

EXAMPLE A method of manufacturing a thin film magnetic head of this example is to form a film dividing groove around each chip formed on a wafer. This embodiment will be described below with reference to FIGS. 1 and 2.

First, according to a conventional method, a coating film made of Al ₂ O ₃ is formed on one surface of a wafer 12 made of Altic as a substrate. Then, a plurality of chips 16, 16, ... Having an electromagnetic conversion element 14, a bonding pad 20, etc. are formed by laminating a lower magnetic layer, a coil conductor, an insulating layer, an upper magnetic layer, etc. by a thin film forming method using sputtering or the like. To be aligned.

Continuing the formation of this thin film causes the wafer 12 to gradually warp due to film stress or the like.
In this embodiment, by forming the film dividing groove 18 around each of the formed chips 16, 16, ..., The lateral film stress generated in the wafer 12 is released, and the wafer 12 is flattened. To do.

As a method of forming the film dividing groove 18, wet etching, dry etching, sputter etching, ion milling, slicer or the like using a mask of resist or metal can be used.

Further, the depth of the film dividing groove 18 is preferably such that there is no warpage, that is, the thickness of the film that causes the film stress.

Furthermore, the width W of the film dividing groove 18 is preferably about 0.4 mm of the blade width of the bar slice or the chip slice which is a post-process.

When cutting the chips 16, 16, ... For processing into sliders, the film dividing groove 18 is used.
The wafer 12 is cut with the boundary as a boundary, and a slider having a flying rail is formed through steps such as polishing to obtain a thin film magnetic head.

By forming the film dividing grooves vertically and horizontally on the wafer as in the present embodiment, it is possible to eliminate the warp of the wafer and enhance the work in the subsequent steps and the accuracy maintenance.

When plating is performed by forming a thin film, a resist or polyimide is applied to the periphery of each chip when the upper and lower magnetic layers are formed, and the resist or polyimide applied after plating is removed. It is also possible to omit forming the film dividing groove.

In this embodiment, the film dividing groove is formed around each chip. However, a plurality of chips are divided into several blocks, and the film dividing groove is formed around each of the blocks to form a wafer dividing wafer. The warp can be eliminated.

[0025]

According to the method of manufacturing a thin film magnetic head of the present invention, a film dividing groove is formed around a chip formed by forming a film on a wafer. No warpage occurs, uneven coating of resist or the like and positional deviation during alignment are less likely to occur,
It is possible to manufacture a highly accurate thin film magnetic head.

Further, even if a film dividing groove is formed around each block for each block composed of a plurality of chips, the warp of the wafer can be eliminated, and uneven coating of resist or the like and misalignment during alignment are caused. It is possible to manufacture a highly accurate thin film magnetic head that is unlikely to occur.

[Brief description of drawings]

FIG. 1 is a plan view of a wafer having a plurality of chips and a film dividing groove for explaining a method of manufacturing a thin film magnetic head according to an embodiment.

FIG. 2A is a plan view of a wafer of this embodiment, and FIG.
[FIG. 3B] is a side view of the wafer according to the present embodiment.

FIG. 3A is a plan view of a conventional wafer, and FIG. 3B is a side view of a conventional wafer.

[Explanation of symbols]

10 wafers 12 wafers 14 Electromagnetic conversion element 16 chips 18 Membrane cutting groove

Claims (2)

[Claims] 1. A lower magnetic layer, a coil conductor, and
In a method of manufacturing a thin film magnetic head by stacking electromagnetic conversion elements having an insulating layer, an upper magnetic layer, etc. by a thin film forming method to form a plurality of chips in an aligned state, cutting these and processing them into sliders, a wafer A method of manufacturing a thin film magnetic head, characterized in that a film dividing groove is formed around each chip during a step of forming a thin film on the substrate. 2. A lower magnetic layer, a coil conductor, and
In a method of manufacturing a thin film magnetic head by stacking electromagnetic conversion elements having an insulating layer, an upper magnetic layer, etc. by a thin film forming method to form a plurality of chips in an aligned state, cutting these and processing them into sliders, a wafer A method of manufacturing a thin film magnetic head, characterized in that a film dividing groove is formed around a block composed of a plurality of chips during a step of forming a thin film on the substrate.