JPH0442416A - Manufacture of thin film magnetic head - Google Patents

Abstract

PURPOSE:To manufacture a tapered part on an insulating layer with high yield by forming the tapered part at a resist terminal part as the mask of the insulating layer consisting of SiO2, and applying etching by RIE(Reactive Ion Etching) to a resist plane in almost perpendicular direction. CONSTITUTION:The insulating layer 13 is formed by vapor-depositing Cu12 on an Si substrate, and laminating an SiO2 on the Cu12, and resist 14 is laminated and formed on the layer, and the tapered part is formed on the terminal part of the resist 14, and also, the etching by the RIE is applied to the resist plane in the almost perpendicular direction. Therefore, it follows that the etching of the insulating layer 13 of SiO2 can be performed in time difference, and the tapered part with a prescribed angle can be manufactured on the insulating layer 13. In such a manner, the tapered part on the insulation layer 13 of SiO2 can be manufactured with high yield.

Description

[Detailed Description of the Invention] Proof! The present invention relates to a method of manufacturing a thin film magnetic head, and more particularly to a method of manufacturing a thin film magnetic head including an insulating layer made of 3102 for maintaining electrical insulation of a conductive coil.

In conventional thin film magnetic heads, fired photoresists have often been used as the insulating layer of the conductive coil.

However, in recent years, with the increase in recording density, GO-based amorphous materials with excellent soft magnetic properties have been used as the magnetic poles of thin-film magnetic heads. Since the temperature is lower than the above-described firing temperature of photoresist (200° C. or higher), insulating materials other than photoresist are increasingly being used. Among these, 5ins, which can be formed by the spuck method, is often used as the insulating material for the coil.

Conventionally, when forming an insulating layer made of Sin, the taper is created by etching the substrate from an oblique direction at the same angle as the taper angle using ion milling. If the angle is 35° to the substrate surface, the incident angle of the ion beam is also 3
Set to 5° and perform ion milling. As a result, the portions of Sin that were masked by the resist remain as they are.

The unmasked portions of SiO□ are etched in accordance with the incident angle of the ion beam, making it possible to create a taper at a targeted angle.

However, when etching the insulating layer by ion milling as described above, it was necessary to apply a resist of about 6 μm to SiO□ of about 2 μm, for example. In other words, the etching rate of resist in ion milling is 2 to 3 higher than 1 for SiO□, and the resist is etched faster than SiOx, so take into consideration that the resist will not be removed by etching. Therefore, it was necessary to form a resist about 3 times thicker than 5ins.2 At this time, a large amount of resist and SiOx removed by ion milling re-attached to the substrate, and the SiOx
This has been a cause of lowering the yield in manufacturing the taper of the insulating layer.

The present invention has been made in view of the above-mentioned problems, and includes 5i
It is an object of the present invention to provide a method for manufacturing a thin film magnetic head that can manufacture a tapered insulating layer made of Oa with a high yield.

Do the lesson. In order to achieve the above-mentioned objects, a method for manufacturing a thin film magnetic head according to the present invention includes the following steps: The ends of the resist serving as a mask of the insulating layer are tapered, and RIE (Reactive I) is applied from a direction substantially perpendicular to the resist surface.
The method is characterized in that etching is performed by etching (on etching), and in providing a taper at the end of the Si island insulating layer, the resist end is tapered at an angle smaller than the target taper angle.

Furthermore, in providing a taper at the end of the 5ift insulating layer in the method for manufacturing the thin JI magnetic head described above, if the target taper angle is φ, the etching rate of Sin is Rs, and the etching rate of the resist is Rr, then the angle is expressed as follows. It is characterized by giving the resist a taper of θ.

■ According to the method for manufacturing a thin film magnetic head described above, 5if
The end portion of the resist serving as a mask for the t-insulating layer is tapered, and R is applied from a direction substantially perpendicular to the resist surface.
When etching is performed by IE, the resist is first etched in the tapered part, and then when the resist is removed, the tapered part is etched.
iOi is etched. Therefore, in the thin portions of the resist, the resist quickly runs out and etching of SiO□ begins, but in the thick portions of the resist, the start of etching of SiO□ is delayed. In other words, by providing a taper to the end of the resist, the insulating layer of Sing is etched with a time difference, and a taper of a desired angle is created in the insulating layer. In addition, in the etching by RIE,
For example, since CF4, a fluorine-based gas, is used as the etching gas, 5i02 is exhausted as 5IF4 gas and does not adhere to the substrate again. Furthermore, since RIE is reactive,
Contrary to ion milling, resist is less likely to be etched than SiO□, and the absolute amount of resist etched is also smaller. Therefore, the amount of redeposited resist that has been etched is reduced.

Furthermore, when a taper with a smaller angle than the target taper angle is given to the end of the resist, when etching is performed by RIE, the etching rate of the resist is higher than that of Si.
Since it is smaller than that of the O□ insulating layer, a taper of the required angle is created in the SiO□ insulating layer.

Furthermore, the target taper angle is φ, the etching rate of Sing is Rs, and the etching rate of resist is Rr.
Then, from the relationship tanθ: tanφ=Rr: Rs,
The taper angle θ of the resist is expressed as follows. In etching by RIE, there is a relationship Rs>Rr as described above, so when the resist is tapered at an angle θ expressed by the above formula, etching by RIE is performed from a direction substantially perpendicular to the resist surface. Then, a taper having a target angle φ is created in the SiO□ insulating layer.

! DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a method for manufacturing a thin film magnetic head according to the present invention will be described below with reference to the drawings.

First, as a preliminary experiment, conditions for producing a taper of an insulating layer of 5 inches were optimized. as a substrate.

Using a Si substrate whose cross section can be easily observed, Cu12 was deposited to a thickness of about 0.3 μm on this Si substrate 11 as shown in FIG. Here, (:u12 was deposited.

When CF4 is used as an etching gas, the Si substrate 11
This is because Si etching may also be etched, which may lead to errors in observing the change in shape due to etching.
Cu12, which is not etched by RIE, was deposited as an end point for ng etching.

Next, 5 iOa was sputtered onto Cu12 to form approximately 2
An insulating layer 13 is formed by laminating μm layers, and a resist 1 is formed on it.
4 was laminated to a thickness of about 0.8 μm. At this time, the ends of the resist 14 were formed to be substantially vertical.

Then, the surface of the laminate thus formed was made parallel to the electrodes, and etched by RIE using CF4, and the etching rate Rs with the optimum conditions and selectivity (Sin) was applied.
(divided by the etching rate Rr of the resist) was calculated. As a result, the optimum conditions and selection ratio were as follows: input power: 700 W, gas pressure: 0, 3 Torr, gas flow rate: 11005 ec, selection ratio: 34. At this time, the etching rate of the insulating layer 13 of 5 iOz was 640 people/min, and the temperature of the base l2iill was approximately 150
It became ℃.

Next, under these optimal conditions, the end of the resist 14 was tapered at an angle θ smaller than the target taper angle φ of the insulation 113, as shown in FIG. Here, resist 1
The taper No. 4 is obtained by adjusting the exposure time and illuminance to the mask (not shown) placed on the resist 14.
Then, by adjusting the heat treatment conditions after removing the mask and forming the resist bag, it is formed at a predetermined angle θ.

Then, CF4 was irradiated onto the resist 14 from a substantially perpendicular direction to perform etching by RIE.

The state of the insulating layer 13 after etching is shown in FIG. 2. In FIG. 2, the portions indicated by broken lines are the resist 14 and the insulating layer 13 that have been removed by the etching. As shown in FIG. 2, when the resist 14 is tapered at an angle θ, the thin portion of the resist 14 is immediately removed and the insulating layer 13 begins to be etched, but the thick portion of the resist 14 is etched. The start of etching is delayed.

Furthermore, the resist 14 remains on the portion of the insulating layer 13 where no taper is formed. In other words.

The SiO□ insulating layer 13 is etched with a time lag, thereby making it possible to create a taper of the target angle φ in the insulating layer 13.

Next, the taper angle θ of the end of the resist 14 is set to 5°10″
15", 20°, 25@,!: When (7) Styx
The measured value of the taper angle ψ of the insulating layer 13 and the calculated value of the taper angle φ of the insulating layer 13 obtained by substituting the selection ratio (Rr/Rs) obtained in the preliminary experiment described above into the following formula are calculated as follows: Shown in the table.

As is clear from Table 1, the measured taper angle ψ of the insulating layer 13 and the calculated value φ are almost the same, and it is possible to give the resist 14 a taper with an angle θ expressed by is found to be effective in forming a taper with a target angle ψ at the end of the insulating layer 13.

Finally, in order to form a 35° taper at the end of the Sing insulating layer 13, the taper angle θ of the resist 14 is adjusted to 11°.
6°, an actual thin film magnetic head was manufactured by the method described above, and the insulating layer 13 was set at 5iys in the manufacturing process.
And the state of re-adhesion of the resist 14 was investigated.

As a result, it was possible to form a taper of approximately 35° at the end of the insulating layer 13. In addition, the etched insulating layer 1
3, Sin, reacts with the etching gas of CF4 to form S.
Since it was exhausted as iF+ gas, no re-deposition was observed. Furthermore, in the RIE etching, the resist 14 was more easily etched than the SiO□ ((,
Since the amount of resist 14 to be etched is also small, the amount of adhered resist 14 is also greatly reduced.

Furthermore, the yield rate was only 91% when the tapered insulating layer 13 was fabricated by conventional ion milling, but by using RIE, the yield increased to over 99%.
A good result was obtained in that there were almost no defects in the taper manufacturing process of the insulating layer 13.

Older brother ΣConventional As is clear from the above explanation, according to the method for manufacturing a thin film magnetic head according to the present invention, a thin film magnetic head equipped with an insulating layer of 5 in 2 for maintaining electrical insulation of a conductive coil is produced. In the manufacturing method.

Since the ends of the resist serving as a mask of the insulating layer are tapered and etching is performed by RIE from a direction substantially perpendicular to the resist surface, the
The insulating layer No. 02 is etched, and a taper of a desired angle can be created in the insulating layer. At that time, etching gas and 310. It reacts with SiO and is exhausted as a gas, and since the absolute amount of resist is small, it is possible to greatly reduce the re-adhesion of etched SiO and resist to the substrate.
The taper of the insulating layer can be manufactured with high yield. In addition, when a taper with a smaller angle than the target taper angle is applied to the resist end, using RIE,
Since the etching rate of the resist is smaller than that of the Sin insulating layer, it is possible to create a taper at a desired angle in the 5in2 insulating layer.

Furthermore, S in the method for manufacturing the thin film magnetic head described above
When applying a taper to the end of the iO□ insulating layer, if the target taper angle is φ, the etching rate of 5iOz is Rs, and the etching rate of the resist is Rr, when applying a taper to the resist at an angle θ, the resist By performing RIE etching on the SiO□ insulating layer, it becomes possible to accurately form a taper with a target angle φ.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional view schematically showing the etching step of the method for manufacturing a thin film 6-ri head according to the present invention, and FIG. 2 is a cross-sectional view schematically showing the state of the tapered portion of the insulating layer after the etching step. It is. 13... Insulating layer 14... Resist patent applicant:
Sumitomo Metal Industries Co., Ltd.

Claims (3)

[Claims] (1) SiO to maintain electrical insulation of conductive coil
In the method for manufacturing a thin film magnetic head having an insulating layer consisting of two layers, the resist end portion serving as a mask of the insulating layer is tapered, and etching is performed by RIE from a direction substantially perpendicular to the resist surface. A method for manufacturing a characteristic thin-film magnetic head. (2) The method for manufacturing a thin-film magnetic head according to claim 1, wherein in providing the end portion of the SiO_2 insulating layer with a taper, the end portion of the resist is tapered at an angle smaller than a target taper angle. (3) In tapering the end of the SiO_2 insulating layer, if the target taper angle is φ, the etching rate of SiO_2 is Rs, and the etching rate of the resist is Rr, then θ=tan^-^1 (tanφ×Rr/Rs) 3. The method of manufacturing a thin film magnetic head according to claim 1, wherein the resist is tapered at an angle θ.