JPS61204877A - Working method for negative pressure floating head slider - Google Patents

Abstract

PURPOSE:To work a negative pressure floating head slider to required working precision quickly and inexpensively by working a parallel plane by the dry etching method and working an inverted taper part by grinding. CONSTITUTION:The most important dimensions of the negative pressure floating head slider are a recess depth H1 in the air inflow end and a recess depth H2 in the air outflow end, and it is necessary to work them with high precision, and normally, the recess depth H1 is set to <=5mum, and the recess depth H2 is set to >=5mum and <=50mum. In this case, a parallel plane 7 is worked by what is called the dry etching method like the ion beam etching method, the sputter- etching method, or the plasma etching method. Meanwhile, an inverted taper surface 8 is worked by conventional grinding.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to a floating head slider used in a magnetic disk drive, and particularly relates to two methods for applying a negative pressure type floating head slider.

[Prior Art] Magnetic disk drives generally use a floating head slider that flies up to a minute gap by using dynamic pressure generated by the running of a magnetic recording medium. This floating head slider has a recording/reproducing magnetic head formed of a magnetic core and a coil. The closer the magnetic head is to the magnetic recording medium surface, the higher the recording density and the greater the output. Therefore, the magnetic head is usually placed at the minimum gap position between the slider surface facing the magnetic recording medium of a floating head slider, that is, at the air outflow end of the slider. be done. The minimum clearance amount is determined by the shape of the slider surface, the load force, and the fluid force caused by the air flow.

The easiest way to reduce the minimum clearance amount is to increase the load force exerted by the spring. However, in the case of a floating head slider that uses the contact start-stop method, the floating head slider and the magnetic recording medium are in contact with each other when the magnetic recording medium is in a stopped state. When the magnetic recording medium is started or stopped, the frictional force between the floating head slider and the magnetic recording medium increases, increasing the possibility of damage at the contact surface between the floating head slider and the magnetic recording medium, and eventually causing damage to the magnetic head. It may occur. On the other hand, a negative pressure type floating head slider has recently been proposed that does not increase the load force and compensates for the lack of load force by using the negative pressure generated by the fluid force to reduce the minimum clearance.

FIG. 2 is a perspective view of such a negative pressure type floating head slider, and FIG. 3 is a sectional view taken along line XX of the negative pressure type floating head slider shown in FIG.

(1) is a negative pressure type floating head slider, (2) is a negative pressure type floating head slider along the running direction of the magnetic storage medium,
Side rails are disposed on both edges, (3) is an air inlet end located in front of the air flow generated by the running of the magnetic recording medium, and (4) is an air inlet end located at the rear with respect to the air flow. An outflow end, (5) is a tapered surface located on the air inflow end (3) side and faces the magnetic recording medium to generate a positive pressure fluid force from the air, and (6) is a tapered surface (5). A floating surface (7) located at the rear of the airflow for generating a positive fluid force by the air flow, is located at the air inflow end (3) between both side rails (2), and is located at the floating surface (6). A parallel plane (8) parallel to
) is a reverse tapered surface that is formed continuously from the parallel plane (7) at the rear of the parallel plane (7), and is used to generate a negative pressure fluid force by the air flow.

In the negative pressure type floating head slider as described above, when airflow flows in the direction shown by arrow U, a positive pressure fluid force is applied to the tapered surface (5) and the floating surface (6). A negative pressure fluid force is generated on the tapered surface (8), and the balance is maintained by three forces, which are these fluid forces plus an external spring force (not shown), so that the floating head slider and magnetic Preventing damage on the contact surface with the recording medium, and
The minimum gap can be reduced.

The conventional processing method for such a negative pressure type floating head slider has generally been a processing method using grinding and polishing.

[Problems to be Solved by the Invention] FIG. 4 is a front view of the air inlet end side of a negative pressure type floating head slider processed by the conventional processing method of grinding and polishing.

In the figure, (9) is a rotary whetstone for grinding, and R is the roundness of the edge portion of the grinding surface of the rotary whetstone (9).

When processing a floating head slider by grinding and polishing in this way, the tapered surface (5) and floating surface (6) can be processed with good processing accuracy, but the parallel surface (7) and the Machining the portion consisting of the tapered surface (8) was difficult in terms of machining accuracy.

In other words, the most important dimension in a negative pressure type floating head slider is the depression f at the air inlet end shown in Figure 3.
f1H1 and the depression amount at the air outflow end 2,
11) The value of H2 directly affects the negative pressure performance of the floating head slider, so it must be processed with high precision.
is usually set in a range of 5 μm or more and 50 μm or less.

Therefore, the machining accuracy of these indentations H1 and H2 is naturally on the order of microns, and the machining accuracy of the indentation iHl is particularly severe. Furthermore, since it is difficult to control the surface shape of the grinding surface of the rotary grindstone (9) on the order of microns, the surface shape is formed by copying the surface shape.

However, the surface machining accuracy of the parallel plane (7) and the reverse tapered surface (8) is naturally affected by this, resulting in variations of several microns. In particular, since the concavity MHI in the parallel ′,·7 plane (7) portion is as small as 5 μm or less, an error of several microns is fatal.

In addition, it is desirable that the corner formed by the side surface of the side rail (2) and the parallel plane (7) intersect perpendicularly, but due to the roundness of the edge of the grinding surface of the rotary grindstone (9), The shape of the curved surface R shown in FIG. 4 has to be an R-shaped corner. The shape of this curved surface R also affects the floating characteristics of the negative pressure type floating head slider and becomes a cause of variation.

As described above, machining a region with a minute depression such as the parallel plane (7) using the rotary grindstone (9) has a problem in terms of machining ti[.

This invention was made to improve the above-mentioned problems, and it provides a processing technology suitable for processing minute areas.
By using this method in combination with conventional grinding, it is possible to provide a method for processing a negative pressure type floating head slider with good precision.

[Means for Solving the Problems] A method for processing a floating head slider according to the present invention is to process the parallel plane (7) by dry etching, and process the other parts by grinding.

[Function] In this invention, the parallel plane (7
) is processed by the dry etching method, so the processing accuracy is particularly good compared to other parts.

[Embodiments of the Invention] FIG. 1 is a front view of an air inlet end side showing an example of a negative pressure type floating head slider processed by the processing method according to the invention.

In this example, the parallel plane (7
) is processed by a so-called dry etching method such as an ion beam etching method, a sputter etching method, or a plasma etching method.

Here, the dry etching method will be briefly explained.

FIG. 5 is a diagram showing the principle of the dry etching method.

In the figure, (11) is the etching gas atmosphere, (l
la> is an etching gas supply port, (11b)
is the etching gas outlet drawn by the vacuum pump, (
12) are plane electrodes arranged in parallel, (13) is a high frequency power source, (14) is a material to be processed, and (15) is a resist film on the material to be processed.

The principle of such a dry etching method is that a high frequency power source (13) is connected between plane electrodes (12) arranged in parallel in an etching gas atmosphere (11) whose pressure is reduced to 1 to 10-5 Torr by a vacuum pump. When high-frequency power with a frequency ranging from several 100 KHl to the microwave region is supplied, the etching gas atmosphere (11) is excited and discharged, generating positive Y, positive ions, and excited atoms (radicals). Therefore, the physical impact and chemical reactivity of these plasmas, ions, and radicals are used to vaporize atoms in the part to be processed of the workpiece material (14) placed on one electrode (12). It is removed and etched.

In the conventional wet etching method, as shown in FIG. 6, side etching and undercut portions (16) occur in the workpiece material (14), resulting in the dimensions of the resulting workpiece being
The shape will deviate significantly from the dimensions and shape of the resist film (15), but with the dry etching method,
The etching cross-sectional shape can be controlled by adjusting the electrode structure, the arrangement of the material to be processed, the type and pressure of the etching gas, etc., and as shown in Figure 7, it is also possible to process without side etching in most cases. Yes, suitable for precision machining.

In this way, in the dry etching method, etching progresses only in the depth direction and does not progress in the lateral direction, because the movement of ions and radicals can be given directionality.

Furthermore, the processing speed in the dry etching method is approximately 4 degrees slower than that in conventional grinding processing, so the dry etching method is suitable for processing minute amounts.

Here, we return to the explanation of FIG.

If processed using such a dry etching method, the right angle portion Δ consisting of the side rail (2) and the parallel plane (7) can be formed into an accurate vertical corner that is not rounded. Become. In addition, as mentioned above, the dry etching method is basically suitable for processing minute quantities.
Amount of concavity 1 at the air inflow end of the parallel plane (7)
It is most suitable for machining minute areas of 5 μm or less, such as No. 1, and enables extremely high-precision machining. On the other hand, the reverse tapered surface (8
) using the dry etching method is inappropriate because the amount of processing increases. The amount of indentation at the air outlet end]2 is in the range of 5 μm to 0 μm or less, so with this degree of suspension, there will be no etching during etching, such as the taper (5) or the floating surface ( 6) The resist film (
15) may be etched first, making etching impossible. In addition, even if there is a strong resist film (15), processing requires a long time,
This is an expensive processing method. Therefore, conventional grinding is suitable for processing the reverse tapered surface (8).

In the grinding process, the corner formed by the side rail (2) and the reverse tapered surface (8) becomes rounded, similar to the curved R-shaped corner shown in Fig. 4, but if the amount of grinding is 5 μm or more, it becomes 50 μm. In the following range, the amount becomes large, so that the influence on the floating characteristics of C becomes small, and in fact becomes almost negligible. Furthermore, although the accuracy of the grinding process is lower than that of the dry etching method, the tolerance range for accuracy becomes wider as the amount of grinding increases, and there is no problem in practical use.

Further, in order to process the reverse tapered portion (8) with higher precision, the following grinding process is used.

First, a slider material (1) with a parallel plane (7) processed by dry etching is prepared. Next, as shown in the front view of the air outlet end side in Fig. 8 and the perspective view in Fig. 9 regarding the floating head slider in the middle of processing, which pair of side rail (2) and reverse tapered surface (8) At the border, add a narrow width (
The narrow groove (17) of W) is ground along the surface of the reverse tapered surface (8) using a rotationally driven grindstone (18),
to drill. Thereafter, by grinding the area defined by both shaft grooves (17) with a wide grindstone, the reversely tapered surface (
8) can be formed.

According to this method, it is possible to almost eliminate the roundness of the corners of the curved surface R-like shape that occurs in conventional grinding processing, and it is possible to form a good reverse tapered surface (8).

[Effects of the Invention] As described above, the present invention provides a parallel plane that is recessed below a floating surface between a pair of side rails that are disposed along the running direction of a magnetic recording medium, and The inverted tapered surface, which is located on the air outflow side of the plane and is formed continuously from the parallel plane, is processed using a dry etching method that is suitable for processing minute amounts and that allows high-precision processing on the parallel plane. The reverse taper part is processed by grinding, which is suitable for large-volume processing and can be processed quickly, rather than dry etching, so it can achieve the required processing accuracy quickly and at low cost. It becomes possible to process a negative pressure type floating IT head slider.

[Brief explanation of the drawing]

Fig. 1 is a front view of the air inlet end side of a negative pressure type floating head slider processed using the processing method of the present invention, Fig. 2 is a perspective view of the negative pressure type floating head slider, and Fig. 3 is the same as Fig. 2. A cross-sectional view of the negative pressure type floating head slider taken along the line X-x. Figure 4 is a front view of the air inflow end side of the negative pressure type floating head slider processed using the conventional processing method. Figure 5 is a dry etching method. Fig. 6 shows an example of processing using the conventional wet etching method, Fig. 7 shows an example of processing using the dry etching method, and Fig. 8 shows a negative pressure type floating head slurry during processing. FIG. 9 is a front view of the air outflow side of the body, and a perspective view of the negative pressure type floating head slider during processing. In the figure, (1)...Negative pressure type floating head slider, (2)...
Side rail, (6)...Floating surface, (7)...
Parallel plane, <i>...Reverse tapered surface, (
17)...Narrow groove. In addition, in the figures, the same reference numerals and the same symbols indicate the same or equivalent parts.

Claims (2)

[Claims] (1) A pair of side rails disposed along the running direction of the magnetic recording medium, a parallel plane disposed recessed from the floating surface of the side rail, and a parallel plane disposed on the air outflow side of the parallel plane. , in a negative pressure type floating head slider having an inverted tapered surface continuously formed from the parallel plane, the parallel plane is processed by dry etching, and the inverted tapered surface is processed by grinding. Processing method for the characteristic negative pressure type floating head slider. (2) The grinding process of the reverse tapered surface is characterized in that a narrow groove is bored at the boundary between a pair of both side guides and the reverse tapered surface, and then the reverse tapered surface is formed by grinding. A method for processing a negative pressure type floating head slider according to scope 1.