JPH10269541A - Multi-step shape forming method and manufacture of magnetic head slider - Google Patents

Abstract

PROBLEM TO BE SOLVED: To form plural steps having different depths on a substrate by using photolithography and dry etching. SOLUTION: This method applies a first resist 2 on a prescribed substrate, and exposure develops it through a prescribed mask. Further, the method applies a second resist 3 to exposure develop it through the mask different from the above mask. Further, similar processes are repeated by the number of the required steps, and after the resists are laminated, a first step is formed by etching. Then, the resist by one layer much is disappeared by ashing, and a second step is formed by the etching again. Further, by repeating similar processes by the number of required steps, plural steps having different depths are obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to silicon and ceramics used as various sensors and actuators,
The present invention relates to an etching method for forming steps on a substrate made of glass or the like, and more particularly to a method for forming a plurality of steps having different heights, and a method for manufacturing a magnetic head slider using the forming method.

[0002]

2. Description of the Related Art In recent years, as typified by micromachine technology, silicon and various ceramic substrates are finely processed into a predetermined shape using semiconductor manufacturing technology, in particular, photolithography and dry etching, and are processed into sensors and actuators. There are many examples of application.
In this case, it is necessary to form a plurality of steps having different depths, such as a groove having various depths and a part of a substrate having a small thickness for controlling rigidity.
In describing these functions and forming methods, a floating magnetic head used in a magnetic disk drive will be described as an example.

In a flying magnetic head used in a magnetic disk drive, the spacing between the disk and the magnetic head, that is, the flying height, is steadily decreasing in order to minimize the so-called spacing loss as the recording density increases. In addition, it is required that the disk be constant from the outer circumference to the inner circumference. As a magnetic head slider that can meet such demands, a modified slider designed based on the fluid dynamics of air has been proposed and put into practical use. The odd-shaped slider is characterized by having a concave portion called a cavity so as to generate a pressure lower than the atmospheric pressure, and is also called a negative pressure slider. Such cavities are difficult to manufacture by conventional mechanical grinding and are generally made by photolithography and dry etching processes.

In recent years, in order to more accurately control the flying height, a device having a plurality of cavities has been proposed, and the present applicant has also proposed a device having a two-stage depth cavity described in Japanese Patent Application No. P-22546. Invented a magnetic head provided with the same.
This is a device to optimize the negative pressure distribution,
A weak negative pressure is generated in the shallow cavity portion and a strong negative pressure is generated in the deep cavity portion, so that the degree of freedom in slider design is greatly increased. In addition, there has been seen an example in which a shallow step is provided instead of the taper at the inflow end of air which has been formed by machining, and this is also a technique adopted to increase the accuracy of the floating characteristics. Thus, recent magnetic heads for high-density magnetic recording tend to have cavities or steps at a plurality of depths in the slider.

In order to form a slider having such a plurality of cavities, (1) aligning, bonding,
A series of steps of (2) application of resist, (3) exposure, (4) development, (5) dry etching, (6) resist and raw bar peeling, and (7) cleaning, are performed by the number of cavity depths. I needed to repeat.

[0006]

However, according to the above-mentioned method, the same step is performed a plurality of times, which not only reduces the production capacity of the production line by half, but also increases the number of steps for handling the row bar. The occurrence of the problem was not negligible. The present invention solves these problems and provides a method capable of easily and stably manufacturing a high-precision irregularly shaped slider, thereby contributing to the realization of a high recording density magnetic disk drive.

[0007]

According to the present invention, a first resist is applied to a row bar in which a slider is arranged in an array, and the resist is exposed and developed through an appropriate mask.
A second resist is applied, and this is exposed and developed using a mask different from the one exposed to the first resist. As a result, there are three types of surfaces: a portion that is not covered by any of the first resist and the second resist, a portion that is covered by either, and a portion that is covered by both. When this is etched using ion milling or reactive ion etching, a raw material that is not covered by any resist
The surface of the bar is etched to form a first cavity.
Next, ashing is performed in plasma to expose a portion covered with only the first or second resist. Thereafter, when etching is performed again by ion milling or reactive dry etching, the surface of the row bar exposed by ashing is newly etched. As a result, a second cavity having a different depth from the cavity formed by the first etching is formed.

According to the present invention, the first dry etching and ashing, and further, the dry etching can be performed in the same dry etching apparatus. It is possible to reduce the number of defects and the occurrence of defects.

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION A step of applying a first resist on a predetermined substrate and exposing and developing the same through a predetermined mask, and a step of applying a second resist and applying a mask different from the aforementioned mask After repeating the same steps by the number of required steps, after laminating the resist, forming a first step by etching, and removing one layer of resist by ashing. ,
Again, a step of forming a second step by etching,
A method of forming a multi-stage shape, wherein the same steps are repeated as many times as required.

A first resist is applied on a predetermined substrate,
A step of exposing and developing this through a predetermined mask, a step of applying a second resist and exposing and developing through a mask different from the above-mentioned mask, and a similar step by the number of required steps After repeating the resist,
The step of forming the first step by etching, the step of removing one layer of resist by ashing, the step of forming the second step by etching again, and the same steps are repeated by the number of steps required further A method of manufacturing a magnetic head slider using a method of forming a multi-step shape, wherein the first resist and the second resist are negative resists.

[0011]

【Example】

(Embodiment 1) An example of a method of manufacturing a magnetic head slider according to the present invention will be described with reference to FIG. Here, all are shown in cross-sectional views. First, as shown in FIG.
The first resist 2 is adhered on top. Here, FRA305-38 (38 μm) manufactured by DuPont MRC was used as a resist.
m thickness), but any negative dry film resist can be used. Further, the film thickness is not limited to 38 μm mentioned here. Attachment was performed with a roller heated to 100 ° C. while peeling off the protective film on the back surface using a laminator.

After cooling, the resist 2 is exposed to ultraviolet light through a predetermined mask, and further developed with a sodium carbonate solution to obtain a first pattern 4 as shown in FIG.
Next, as shown in FIG. 1C, the dry film resist is again applied as the second resist 3 on the row bar 1 on which the first pattern 4 is formed. Here, the second resist is the same as the first resist 2, and was similarly adhered. Next, the second resist 3 is again exposed and developed through a predetermined mask, and a second pattern 5 is obtained as shown in FIG. At this time, it goes without saying that the mask has a shape different from that of the first pattern 4. Here, the resist 1 having the first pattern 4 passes through the development process twice, but usually, the dry film resist does not become thinner in the development twice or so, and the development is performed three or more times. On the other hand, since there is a tendency to decrease in proportion to the number of times, there is no problem in quality control.

Next, the row bar 1 provided with the resist having the first and second patterns is put into a reactive ion etching apparatus, and the row bar is etched to a depth of 3 μm. Thus, the first cavity 6 was formed. At this time, although the thickness of the first resist 2 is reduced, about 20 μm still remains.

Next, while holding the row bar in the etching apparatus, an argon gas containing 10% oxygen is introduced, and this is turned into plasma to form a second pattern 5 as shown in FIG. Ashing of the resist is performed until is reflected on the surface of the row bar 1. At this time, a bias of −200 V was applied to the row bar 1. Ashing can be performed by introducing only oxygen gas, and the processing speed is short. However, the side surface of the resist is severely recessed, and the accuracy of the second pattern 5 is reduced. By converting argon containing oxygen into plasma and applying a negative bias to the low bar 1 as in the present embodiment, the resist removal can be made anisotropic and the second pattern 5 can be obtained with high accuracy. Was. Therefore, when the processing speed is more important than the accuracy, the combination of oxygen plasma and bias application may be selected. However, if the bias is too high, the exposed surface of the low bar 1 after resist ashing is etched, which may cause a problem in accuracy in the depth direction.

Next, reactive ion etching was performed again to obtain a second cavity 7 as shown in FIG.
Here, the depth of the second cavity 7 is 0.5 μm, but the depth of the first cavity 6 is of course 3.5 μm. The resist is completely removed, and a cavity having two depths is completed. The row bar 1 in which the cavity is formed as described above is cut into individual heads to complete a magnetic head slider as shown in FIG.

(Embodiment 2) In Embodiment 1, etching was performed by using reactive ion etching. However, the same manufacturing was possible by using an ion milling method using an RF ion beam etching apparatus. However, since the ion beam etching apparatus originally has anisotropy, there was no need to apply a bias to the row bar 1 during ashing.

In the above embodiment, the first resist 2
Although the example in which the opening of the second pattern 5 formed of the second resist 3 is larger than that of the first pattern 4 formed of the second pattern 5 is not limited to this combination, the second pattern 5 However, there is no problem even if the first pattern 4 partially covers the first pattern 4. Further, the substrate is not limited to the one described in the embodiment. Needless to say, silicon and various ceramics are used, and the depth of the step is not limited to two steps.

[0018]

As described above, according to the present invention, a negative pressure slider having a plurality of cavities having different depths can be manufactured easily and stably, and furthermore, a high-density high-capacity magnetic disk drive. It will contribute to the spread of computers and the spread of computers with excellent information processing capabilities. Further, when applied to the processing of silicon and various ceramics substrates, a multi-stage shape required for small sensors and actuators can be obtained, which contributes to its spread.

[Brief description of the drawings]

FIG. 1 is a schematic view showing an example of a magnetic head slider manufactured according to the present invention.

FIG. 2 is a schematic view showing one example of a manufacturing process of a magnetic head slider according to the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Low bar 2 Resist 1 3 Resist 2 4 First pattern 5 Second pattern 6 First cavity 7 Second cavity

Claims (4)

[Claims] A step of applying a first resist on a predetermined substrate and exposing and developing the first resist through a predetermined mask;
A step of applying a second resist, exposing and developing through a mask different from the above-described mask, and repeating the same steps as many times as the number of required steps, laminating the resist, and etching the first A step of forming a step and ashing to erase one layer of resist, and again
A method of forming a multi-step shape, wherein a step of forming a second step by etching and a similar step are repeated by the number of steps required further. 2. a step of applying a first resist on a predetermined substrate, and exposing and developing the first resist through a predetermined mask;
A step of applying a second resist, exposing and developing through a mask different from the above-described mask, and repeating the same steps as many times as the number of required steps, laminating the resist, and etching the first A step of forming a step and ashing to erase one layer of resist, and again
A method of manufacturing a magnetic head slider using a multi-step forming method characterized by repeating a step of forming a second step by etching and a similar step by the number of steps required further, wherein A method for manufacturing a magnetic head slider, wherein the first resist and the second resist are negative resists. 3. The method according to claim 2, wherein the ashing is performed in a plasma containing argon and oxygen. 4. The method according to claim 2, wherein the ashing is performed by applying a negative bias to a surface to be processed.