SLIDER EDGE FEATURES
A slider comprising a body having an air bearing surface (ABS), wherein the ABS extends between a leading edge and a trailing edge of the body. The slider comprises a transducer supported by the body and positioned near the trailing edge, wherein the transducer comprises a pole tip partially extending from the body. The slider comprises a surface defined in the body and forming the trailing edge, wherein the surface comprises a plurality of segments. A first segment of the plurality of segments extends from the ABS and is offset from a portion of the pole tip recessed within the body. The first segment is offset from the pole tip portion by a lesser extent than any other of the plurality of segments.
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Basic parts of a disc drive generally include a disc that is rotated, an actuator that moves a transducer to various locations over the disc, and electrical circuitry that is used to write and read data to and from the disc. Typically, the transducer functions with the electrical circuitry, translating electrical signals into magnetic field signals for recording data “bits” to the disc, or vice versa for reading data “bits” from the disc.
The transducer is generally housed within a small ceramic block known as a slider, with the slider being passed over the rotating disc at a certain fly height. Generally, greater performance of the disc drive results when the slider is flown as closely to the surface of the disc as possible. In operation, the distance between the slider and the disc, or “fly” heights or head media spacing, can be in the range of micro inches. It is contemplated that fly heights will continue to be reduced, for this is one factor in achieving increased recording density. However, this will require considerable care or else head/media intermittent contact can result. Such contact induces vibrations detrimental to the reading/writing quality at such low fly height, and can also eventually result in a head crash and total loss of data.
One manner by which head media spacing has been decreased to date is via shaping the alumina located at the trailing edge of the slider. Typically, the slider is formed from a wafer of ceramic material. The transducer or transducers (separate read and write elements) are placed onto the wafer and then encased in alumina. Once encased, the wafer is diced to form individual heads, and then the alumina is shaped to include various features. Shaping the alumina at the trailing end of the slider can be beneficial in enabling the head to fly at decreased spacing with respect to the media. However, the conventional shaping process can result in alumina features being inconsistently formed from head to head. Such inconsistency can in turn lead to undesirable variance in fly height from slider to slider. A reason for such variance is that the alumina features are formed at the bar level, or after the wafer has been cut into individual heads. Consequently, the corresponding cuts are often found to vary from head to head, leading to inconsistency in fly heights for the heads, and inconsistent results being obtained during reading and recording of data.
SUMMARYIn certain embodiments of the invention, a slider is provided. The slider comprises a body having an air bearing surface (ABS), wherein the ABS extends between a leading edge and a trailing edge of the body. The slider comprises a transducer supported by the body and positioned near the trailing edge, wherein the transducer comprises a pole tip partially extending from the body. The slider comprises a surface defined in the body and forming the trailing edge, wherein the surface comprises a plurality of segments. A first segment of the plurality of segments extends from the ABS and is offset from a portion of the pole tip recessed within the body. The first segment is offset from the pole tip portion by a lesser extent than any other of the plurality of segments.
These and various other embodiments, features, and advantages will be apparent from a reading of the following detailed description.
The following detailed description should be read with reference to the drawings, in which like elements in different drawings are numbered identically. Embodiments shown in the drawings are not necessarily to scale, unless otherwise noted. It will be understood that embodiments shown in the drawings and described herein are merely for illustrative purposes and are not intended to limit the invention to any embodiment. On the contrary, it is intended to cover alternatives, modifications, and equivalents as may be included within the scope of the invention as defined by the appended claims.
Embodiments of the invention described herein focus on sliders. As alluded to above, a slider is formed with a transducer. As detailed herein, the slider can be shaped so that the transducer's read/write performance is enhanced. As further detailed, material forming the slider is shaped during steps of fabricating the slider. While slider embodiments described herein exemplify sliders being formed of alumina (a material that has been conventionally used), it should be appreciated that the invention is also applicable to sliders formed of other suitable alternative material(s). Further, while sliders are described herein with respect to their applicability in drives (such as hard disc drives, zip drives, floppy disc drives and any other type of drives), it should be appreciated that the invention is just as applicable to other apparatus configured to utilize a slider with transducer.
In certain embodiments, as shown, moving the actuator assembly 120 moves all the load springs 124 in unison. In operation, the actuator assembly 120 is moved to a park position when the disc drive is powered down. Alternatively, when the disc drive is powered on, the actuator assembly 120 can be used to move the sliders 300 into an operating or transducing position over the area of the disc used to read or write information representative of data. The actuator assembly 120 can also be used to seek various data locations on the surface of the disc. As shown, a spindle hub 133 can be used for rotating the one or more discs 200. In this embodied disc drive, a spindle motor is within the hub 133. The discs 200 are accelerated to a speed whereby relative velocity between the sliders 300 and corresponding discs 200 would cause such sliders 300 to lift off the surface of the discs 200.
With further reference to
In
As further shown in
Controlling the exact formation of the corner of the center pad second portion and its trailing edge surface is difficult given the very small spacing and different methods of manufacture, which when collectively considered, can explain why alumina area of the center pad second portion can vary. However, alumina variation is detrimental to the head/disc interface because it introduces larger variability in fly height. In other words, sliders having different amounts of alumina at their trailing edges, albeit even minute differences, can consequently lead to significant variation in fly heights between the sliders. As can be seen from
In comparison to the configuration shown in
While such cutting or shaping processes are stringently controlled, the very minute surfaces of the center pad trailing edges enhance the level of difficulty in controlling the process. To that end, as described above, the conventional process generally involves such cutting or shaping steps taking place at the bar level, or after the wafer has been cut into individual heads. Controlling a shaping process with such microscopic heads is quite difficult, let alone repeatedly performing such process on an individual basis. Variations, while minute, are known to occur, and with such variation, the resulting sliders can be found to exhibit inconsistencies in their fly heights.
To that end, it has been determined that using shaping and cutting processes further upstream in the slider fabrication process is a more effective approach. In certain embodiments, alumina shaping and cutting steps are performed at the wafer level. As detailed herein, performing these steps at this stage of the fabrication process allows for a more controllable platform as opposed to being performed at the microscopic bar level. Additionally, using the wafer as the platform, in which stacked rows of transducers are encased in alumina, cutting and shaping steps can be performed on row after row of the transducers prior to the rows being cut from the wafer into individual heads.
In reference to flowchart 1100 of
In reference to flowchart 1100 of
In reference to flowchart 1100 of
As described above,
Further, being able to remove excess alumina proximate the pole tip 462 provides less potential interference to the read and write performance characteristics of the tip 462. Any excess alumina provided proximate to the pole tip 462 can be found to hinder its performance, but with such alumina being minimized proximate to the tip 462, this concern is likewise minimized.
Starting with the graph of
While the embodied method provides flexibility to etch the alumina as close to the tips 462 as desired, etching too close could prove costly and possibly cause damage to the pole tip 462. From
Thus, embodiments of the present invention are disclosed. Although the present invention has been described in considerable detail with reference to certain disclosed embodiments, the disclosed embodiments are presented for purposes of illustration and not limitation. The implementations described above and other implementations are within the scope of the following claims.
Claims
1. A slider, the slider comprising:
- a body having an air bearing surface (ABS), the ABS extending between a leading edge and a trailing edge of the body;
- a transducer supported by the body and positioned near the trailing edge, the transducer comprising a pole tip partially extending from the body; and
- a surface defined in the body and forming the trailing edge, the surface comprising a plurality of segments, a first segment of the plurality of segments extending from the ABS and offset from a portion of the pole tip recessed within the body, the first segment offset from the pole tip recessed portion by a lesser extent than any other of the plurality of segments, the first segment being less than 450 nm from the pole tip recessed portion.
2. The slider of claim 1 wherein the body comprises a single center pad forming the trailing edge, and wherein the trailing edge is formed of a portion of the single center pad comprising alumina.
3. The slider of claim 1 wherein a substantially uniform thickness of material is defined between the pole tip recessed portion and the first segment.
4. The slider of claim 3 wherein the material comprises alumina.
5. The slider of claim 1 wherein the plurality of segments comprises a second segment extending from the first segment, wherein the second segment extends from the first segment at an angle of greater than 90 degrees.
6. The slider of claim 1 wherein the first segment runs substantially parallel to the pole tip recessed portion.
7. A slider, the slider comprising:
- a body having an air bearing surface (ABS), the ABS extending between a leading edge and a trailing edge of the body;
- a transducer supported by the body and positioned near the trailing edge, the transducer comprising a pole tip partially extending from the body; and
- a surface defined in the body and forming the trailing edge, the surface comprising a plurality of segments, a first segment of the plurality of segments extending from the ABS and offset from a portion of the pole tip recessed within the body, the first segment offset from the pole tip recessed portion by a lesser extent than any other of the plurality of segments, a second segment of the plurality of segments extending from the first segment at an angle of greater than 90 degrees.
8. The slider of claim 7 wherein the body comprises a single center pad forming the trailing edge, and wherein the trailing edge is formed of a portion of the single center pad comprising alumina.
9. The slider of claim 7 wherein a substantially uniform thickness of material is defined between the pole tip recessed portion and the first segment.
10. The slider of claim 9 wherein the first segment runs substantially parallel to the pole tip recessed portion.
11. The slider of claim 9 wherein the material comprises alumina.
12. The slider of claim 7 wherein the angle of the second segment enables air to rise gradually as the air flows from under the ABS, so as to maintain fly height of the slider when the slider is flown above a recording medium.
13. The slider of claim 12 wherein the recording medium comprises a disc, and wherein the slider is part of a disc drive.
14. The slider of claim 7 wherein the first segment is less than 450 nm from the pole tip recessed portion.
15. A method of shaping a trailing edge of a slider, the method comprising:
- encasing a transducer in alumina, the transducer on a wafer of ceramic material and including a pole tip;
- forming a trench above an end of the pole tip; and
- making a series of cuts into the alumina relative to a pole tip of the transducer to differentiate a slider head.
16. The method of claim 15 wherein the ceramic material comprises AlTiC.
17. The method of claim 15 wherein the transducer is a part of a plurality of transducers provided in one or more rows on the wafer.
18. The method of claim 17 wherein the trench is one of a plurality of trenches each of which is consistently formed with respect to one of the transducer pole tips.
19. The method of claim 18 wherein each of the trenches is formed using an etching process.
20. The method of claim 18, wherein each of the trenches includes a first segment that runs substantially parallel to the corresponding pole tip and a second segment that extends from the first segment at an angle of greater than 90 degrees.
Type: Application
Filed: Feb 17, 2012
Publication Date: Aug 22, 2013
Applicant: SEAGATE TECHNOLOGY LLC (Cupertino, CA)
Inventors: Gordon Merle Jones (Faribault, MN), Edwin Frank Rejda (Bloomington, MN), Joseph Michael Stephan (Eden Prairie, MN)
Application Number: 13/399,782
International Classification: G11B 5/60 (20060101); G11B 5/48 (20060101);