Abstract:
An apparatus for reader characterization is described. The apparatus includes a rotator for rotating a media. The media can contain a signal having a value for a function of a read/write head being assessed. The rotator is operable in conjunction with said apparatus. The apparatus also includes a proximator for proximalizing the media to the read/write head. The proximator is operable in conjunction with said apparatus. The apparatus further includes a writer operable in conjunction with said assembly. The writer writes the signal upon the media. The signal emits the value of the function. The signal is detectable by a reader of the read/write head. The apparatus additionally includes an interface operable in the apparatus for providing removable orientation of the read/write head in an assessing position. The assessing position enables a reader of the read/write head to detect the signal upon rotation of the signal through the assessing position.

Description:
FIELD OF THE INVENTION  
       [0001]     The present invention relates to magnetic head fabrication. More particularly, the present invention provides an apparatus for assessing reader recording characterization at the slider or bar level during magnetic head fabrication.  
       BACKGROUND OF THE INVENTION  
       [0002]     Hard disk drives are used in almost all computer system operations. In fact, most computing systems are not operational without some type of hard disk drive to store the most basic computing information such as the boot operation, the operating system, the applications, and the like. In general, the hard disk drive is a device which may or may not be removable, but without which the computing system will generally not operate.  
         [0003]     The basic hard disk drive model was established approximately 40 years ago and resembles a phonograph. That is, the hard drive model includes a plurality of storage disks or hard disks vertically aligned about a central core that spin at a standard rotational speed. A plurality of magnetic read/write transducer heads, for example, one head per surface of a disk, is mounted on the actuator arm. The actuator arm is utilized to reach out over the disk to or from a location on the disk where information is stored. The complete assembly, e.g., the arm and head, is known as a head gimbal assembly (HGA).  
         [0004]     In operation, the pluralities of hard disks are rotated at a set speed via a spindle motor assembly having a central drive hub. Additionally, there are channels or tracks evenly spaced at known intervals across the disks. When a request for a read of a specific portion or track is received, the hard disk drive aligns a head, via the arm, over the specific track location and the head reads the information from the disk. In the same manner, when a request for a write of a specific portion or track is received, the hard disk drive aligns a head, via the arm, over the specific track location and the head writes the information to the disk.  
         [0005]     Over the years, refinements of the disk and the head have provided great reductions in the size of the hard disk drive. For example, the original hard disk drive had a disk diameter of 24 inches. Modern hard disk drives are generally much smaller and include disk diameters of less than 2.5 inches (micro drives are significantly smaller than that). Refinements also include the use of smaller components and laser advances within the head portion. That is, by reducing the read/write tolerances of the head portion, the tracks on the disk can be reduced in size by the same margin. Thus, as modem laser and other micro recognition technology are applied to the head, the track size on the disk can be further compressed.  
         [0006]     A second refinement to the hard disk drive is the increased efficiency and reduced size of the spindle motor spinning the disk. That is, as technology has reduced motor size and power draw for small motors, the mechanical portion of the hard disk drive can be reduced and additional revolutions per minute (RPM) can be achieved. For example, it is not uncommon for a hard disk drive to reach speeds of 15,000 RPM. This second refinement provides weight and size reductions to the hard disk drive and increases the linear density of information per track. Increased rates of revolution also provide a faster read and write rate for the disk and decrease the latency, or time required for a data area to become located beneath a head, thereby providing increased speed for accessing data. The increase in data acquisition speed due to the increased RPM of the disk drive and the more efficient read/write head portion provide modem computers with hard disk speed and storage capabilities that are continually increasing.  
         [0007]     Particularly, with regard to data storage devices, these advances have attributed to increases in storage density. However, the increase in storage density has led to weaker and/or smaller signal strength emitted by each data bit. This has required the development of read/write heads having increased sensitivity to the intensity of the signals emitted by the data bits. Increased sensitivity needs require improved testing techniques to ensure proper and precise functioning of the read/write head.  
         [0008]     Specifically, within the read/write head fabrication and assembly process, there are general processes that are performed on the read/write head prior to the read/write head being mounted into the hard disc drive assembly. Prior art  FIG. 1A  is an exemplary flowchart  10  of a process for fabrication and testing of a read/write during certain stages of the fabrication process.  
         [0009]     Step  11  is the wafer fabrication. This step is where the components of the read/write head are created. Examples of some of the components that may be implemented in a read/write head fabricated on the wafer may include a magnetic shield layer(s), the pinned layer, the conductive spacer layer, the free layer (sensor), the contact layer, the writer layer, and additional layers and/or components. There may be thousands of read/write heads fabricated on a single wafer.  
         [0010]     Subsequent to completing wafer fabrication  11 , the process continues to step  12 , slider fabrication  12 . Slider fabrication  12  is a process for cutting the wafers into thousands of individual sliders where each slider has a reader and a write element and a proper air-bearing surface on one side of the slider. Slider fabrication can include slicing the read/write head from the wafer, lapping each slider to achieve a proper reader strip height and resistance, are on design target, and to define the air-bearing surface. Slider fabrication can also include depositing a protective overcoat for protection against corrosion and head disk interface robustness.  
         [0011]     Subsequent to the lapping process in slider fabrication  12 , the process proceeds to step  13 , a quasi-static test (QST). QST  13  is for testing reader signal amplitude (sensor sensitivity), reader asymmetry (similar peak to peak readings for a waveform) and reader instability. QST  13  has several shortcomings, one of which is while QST  13  is a functional test it is not a direct test. For example, the slider is placed into conventional magnetic field, referred to as a uniform field. This uniformity does not replicate the field emitted from a platter (disc) as the disc emits small local fields. The measurement can also be affected by changes in reader shield shapes and properties.  
         [0012]     A further shortcoming to QST  13  using a uniform field is that QST  13  does not test the read/write head for recession, protrusion, or other deformity. If the read/write head has recessions, the reader is not disposed on the edge of the air-bearing surface (ABS). Because of the applied uniform field, the transducer is not effectively screened. If the read/write head is not disposed at the ABS, the read/write head will not function properly when applied to a disc where each bit region may emit varying charge states. A uniform field only determines if the head can sense, not the sensing accuracy of the read/write head  
         [0013]     Another shortcoming to QST  13  is matching the characteristics of the local small fields emitted from a disc. To enable this, an offset is provided in case of change in design of a shield. The shield is a structure that isolates the reader from adjacent bit fields, thus providing better resolution. When the reader reads from one bit space, the reader is not influenced by an adjacent bit region. However, the shield provides an extra field during QST  13 . Thus, when the data relative to the extra field in the shield is accessed, a correction factor is needed. Further, when the reader or shield design changes or an alternatively designed reader is subject to QST  13 , the correction factors required modifications. While QST  13  can return favorable numbers within the static test, QST  13  does not adequately address reader value quality and/or real performance, and the results vary upon fabrication inconsistencies and design changes. For example, if QST  13  gives a number 10 (acceptable for one design) and then gives the number 10 for another design, this number may not be correct because of the shielding characteristics. QST  13  requires adjustment to obtain the real value, and the value varies from configuration to configuration. The value is not uniform nor is the value universally applicable. If the read/write head fails QST  13 , the read/write head is rejected, e.g., sent to disposal  20 .  
         [0014]     However, upon the read/write head passing QST  13 , the read/write head slider is then sent to step  14 , head gimble assembly process (HGA)  14 . In HGA  14 , the read/write head slider is mounted to an entire assembly, the head gimble assembly. The HGA includes the slider and the suspension, the flex component. The slider is commonly bonded to the suspension. The suspension has a spring-like quality, which causes the air-bearing surface of the read/write head slider to be placed against the platter to cause the slider to fly at a precise distance from the platter.  
         [0015]     Once the HGA is completed in step  14 , the process proceeds to step  15 , a dynamic electrical test (DET)  15 , also referred to as a magnetic dynamic test (MDT). DET  15  has been implemented for testing read/write head performance as a QST  13  does not test for characteristical deficiencies in the read/write head slider. DET  15  tests an entire HGA assembly.  
         [0016]     Digressing from flowchart  10 ,  FIG. 1B  shows an exemplary test machine  30  for performing DET  15  of  FIG. 1A . It is common for a test machine  30  to cost upwards of a quarter of a million dollars (US) per machine. Further, it is not uncommon for companies making hard disk drives to have hundreds or thousands of test machines  30  for performing a DET  15 . Shown in  FIG. 1B  are HGA  25  and mounted slider  26 . HGA  25  is removably mounted to a device  34 . Device  34  is for orienting HGA  25  upon the magnetic data layer of platter  50 . Device  34  can move HGA  25  as indicated by arrow  33 .  FIG. 1B  also includes device  31  for rotating a platter  50 . Device  31  can rotate platter  50  as indicated by arrow  51 . Device  31  rotates platter  50  at a speed equivalent to the rotational speed of the platters in the hard disc drive into which HGA  25  is to be placed. Also shown is a data collector  32  that collects data acquired from devices  31 , platter  50 , and device  34  during performance of DET  15 . DET  15  is fully capable of detecting most characteristical deficiencies and physical problems that may be present in slider  26  and/or HGA  25 .  
         [0017]     However, DET  15  has some shortcomings. One shortcoming is the cost of DET  15  is non-trivial. Costs can include, but which are certainly not limited to, assembly of an HGA  25  (slider on suspension), placing the HGA into a cartridge for mounting to the expensive testing machinery, labor costs for performing the test, clean room real estate allocated for the testing machinery, cost of the machinery, etc.  
         [0018]     Referring back to  FIG. 1A , specifically step DET  15  of process  10 , when a reader component, e.g., read/write head slider  26  of HGA  25 , tests to have acceptable reader characteristics, process  10  proceeds to step  16 , a head assembly process. If a read/write head fails DET  15 , the entire HGA  25  assembly is then rejected, e.g., disposal  20 . Continuing, process  10  then proceeds to step  17 , a drive assembly process. Then process  10  proceeds to a final test  18 , and if the assembly passes, on to step  19 , the delivery of completed hard drives.  
         [0019]     However, if the reader (transducer) component of HGA  25 , e.g., read/write head slider  26 , tests such that the characteristics of the reader according to DET  13  are unsatisfactory, the entire HGA  25  is discarded, e.g., disposal  20 . It is noted that discarding an HGA  25  is a non-trivial cost.  
       SUMMARY OF THE INVENTION  
       [0020]     An apparatus and method for characterizing a fabricated read/write head is described. In an embodiment of the present invention, the apparatus for reader characterization is described. The apparatus includes a rotator for rotating a media. The media can contain a signal having a value for a function of a read/write head being assessed. The rotator is operable in conjunction with said apparatus. The apparatus also includes a proximator for proximalizing the media to the read/write head. The proximator is operable in conjunction with said apparatus. The apparatus further includes a writer operable in conjunction with said assembly. The writer writes the signal upon the media. The signal emits the value of the function. The signal is detectable by a reader of the read/write head. The apparatus additionally includes an interface operable in the apparatus for providing removable orientation of the read/write head in an assessing position. The assessing position enables a reader of the read/write head to detect the signal upon rotation of the signal through the assessing position.  
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0021]     The accompanying drawings, which are incorporated in and form a part of this specification, illustrate embodiments of the invention and, together with the description, serve to explain the principles of the invention:  
         [0022]      FIG. 1A  is a prior art diagram of a flowchart showing portions of a conventional read/write head fabrication and testing process.  
         [0023]      FIG. 1B  is a prior art block diagram of a conventional DET testing device for performing electrical tests during the read/write head fabrication process of  FIG. 1A .  
         [0024]      FIG. 2A  is an illustrated top-view schematic of components of a hard disc drive upon which embodiments of the present invention can be practiced, in accordance with an embodiment of the present invention.  
         [0025]      FIG. 2B  is an exploded view block diagram of a read/write head component of  FIG. 2A  upon which embodiments of the present invention can be practiced, in accordance with an embodiment of the present invention.  
         [0026]      FIG. 3  is a block diagram of a fabricated read/write head slider in accordance with an embodiment of the present invention.  
         [0027]      FIG. 4  is a schematic block diagram of a testing apparatus for characterizing a fabricated read/write head slider, in accordance with an embodiment of the present invention.  
         [0028]      FIG. 5  is a flowchart of a test process applied upon a fabricated read/write head slider, in accordance with an embodiment of the present invention.  
     
    
     DETAILED DESCRIPTION  
       [0029]     An apparatus and method for testing characteristics of a read/write device in a slider and/or a bar slider is described. In the following description, for purposes of explanation, numerous specific details are set forth in order to provide a thorough understanding of the present invention. It is noted that one skilled in the art will comprehend that the present invention may be practiced without these specific details. In other instances, well-known structures and devices are shown in block diagram form in order to avoid obscuring the present invention.  
         [0030]     Some portions of the detailed descriptions, which follow, are presented in terms of procedures, steps, logic blocks, processing, and other symbolic representations of operations that can be performed in the fabrication and testing of read/write devices. These descriptions and representations are the means used by those skilled in the data processing arts to most effectively convey the substance of their work to others skilled in the art. A procedure, executed step, logic block, process, test, etc., is here, and generally, conceived to be a self-consistent sequence of steps, instructions, or tests leading to a desired result. The steps are those requiring physical manipulations of physical entities. Usually, though not necessarily always, these entities take the form of structures, elements, layers implemented and tested during the fabrication of read/write device assemblies. It is usual, although not always, that the manipulations, alone or in combination with computer implemented instructions, and tests are performed by a machine particular to the structure and to the manipulation being performed.  
         [0031]     It should be borne in mind, however, that all of these and similar terms are to be associated with the appropriate physical entities and are merely convenient labels applied to these entities. Unless specifically stated otherwise as apparent from the following discussions, it is appreciated that throughout the present invention, discussions utilizing terms such as “rotating” or “writing” or “detecting” or “reading” or “providing” or “proximalizing” or “disposing” or “comparing” or the like, refer to the actions and processes of a read/write device fabrication process or similar technique that manipulates and transforms those entities into operable read/write devices or other such data storage enabling devices.  
         [0032]     The present invention is discussed primarily in the context of assessing the functional characteristics of read/write device assemblies, such as a current perpendicular plane (CPP) or a current in plane (CIP) reader device. Embodiments of the present invention are well suited to be utilized in testing perpendicular and longitudinal recordings. Further, it is noted that the present invention can be used with other types of read/write devices and associated fabrication devices that have the capability to affect access upon a storage device and from which data can be stored and/or otherwise manipulated.  
         [0033]     With reference now to  FIG. 2A , a schematic drawing of one embodiment of an information storage system comprising a magnetic hard disk file or drive  200  for a computer system is shown. Drive  200  has an outer housing or base  210  containing a disk pack having at least one media or magnetic disk  215 . The disk or disks  215  are rotated (see arrows  206 ) by a spindle motor assembly having a central drive hub  217 . An actuator  221  comprises a plurality of parallel actuator arms  225  (one shown) in the form of a comb that is movably or pivotally mounted to base  210  about a pivot assembly  223 .  
         [0034]     In the embodiment shown, each arm  225  has extending from it at least one cantilevered load beam and a suspension  227 . A slider  229  includes a magnetic read/write transducer or head is mounted or secured to a suspension  227 . The read/write devices magnetically read data from and/or magnetically write data to disk  215 . The level of integration called the head gimbal assembly is slider  229 , mounted to suspension  227 . The slider  229  is usually bonded to the end of suspension  227 . The head is typically “pico” size (approximately 1250×1000×300 microns) and formed from ceramic or intermetallic materials. The head also may be of “femto” size (approximately 850×700×230 microns) and is pre-loaded against the surface of disk  215  (in the range two to ten grams) by suspension  227 . It is noted that alternative sized heads may also be implemented.  
         [0035]     Suspensions  227  have a spring-like quality, which biases or urges the air-bearing surface of the slider  229  against the disk  215  to cause the slider  229  to fly at a precise distance from the disk. A voice coil  233  free to move within a conventional voice coil motor magnet assembly  234  (top pole not shown) is also mounted to arms  225  opposite the head gimbal assemblies. Actuator  221  moves the head gimbal assemblies (indicated by arrow  235 ) along radial arcs across tracks on the disk  215  until the heads settle on their respective target tracks. The head gimbal assemblies operate in a conventional manner and always move in unison with one another, unless drive  211  uses multiple independent actuators (not shown) wherein the arms can move independently of one another.  
         [0036]      FIG. 2B  is an exploded view of a suspension  227  as shown in  FIG. 2A . Upon suspension  227  are shown a slider  229  and a read/write device  260 . Slider  229  is the intermediate component to which read/write device  260  is embedded at its trailing edge. Read/write device  260  magnetically reads data from and/or magnetically writes data to disk  215  ( FIG. 2A ). Read/write device  260  is for sensing a charge state of a data bit of disc  215  and for affecting a change in a charge state. Read/write device  260  is oriented to be operable proximal to the gap between the bottom surface of read/write device  260 , e.g., surface  290 , and the data bearing surface of disc  215 . Surface  290  is commonly referred to the air-bearing surface (ABS). Embodiments of the present invention provide an apparatus and method for assessing the functioning of a read sensor (e.g., read sensor  306  of  FIG. 4 ) of read/write device  260  while disposed on slider  229 .  
         [0037]      FIG. 3  is a front-facing block diagram illustrating a slider  300 , subsequent to the slicing thereof and readied for testing, in an embodiment of the present invention. Slider  300  is implementable as and functionally analogous to slider  229  of  FIGS. 2A and 2B . It is noted that many prior processes have been performed on slider  300  to reach a testing stage including, but not limited to, lithography, deposition (vacuum, plating, or sputtering), sensor deposition, shunt deposition, etching, and slicing. Examples of etching processes can include, but which is not limited to, broad-beam ion etching, reactive ion etching, ion-beam etching, polymer etching, and other similar processes.  
         [0038]     With continued reference to  FIG. 3 , in an embodiment, subsequent to fabrication and slicing, slider  300  is shown to include a read/write device  305  and an air-bearing surface (ABS)  320 . In the exploded view of read/write device  305 , included are a read sensor  306 , a write device  307 , and a plurality of magnetic shields  308 . Read sensor  306  and write device  307  are for reading from and writing to a field from a data storage device, e.g., a hard disc  215  of  FIG. 2B , respectively. Magnetic shields  308  are for protecting against read sensor  306  detecting states of charge from data fields other than the data field intended to be sensed. Shown also is surface  320 , the air-bearing surface of slider  300 .  
         [0039]      FIG. 4  is a schematic block diagram of a tester  400  for performing a test  520  ( FIG. 5 ). Test  520  is for assessing the functions and characteristics of a read sensor  306  in a read/write device mounted in a slider, e.g., read/write device  305  of slider  300  of  FIG. 3 , in an embodiment of the present invention, and as described herein with reference to  FIG. 5 . Tester  400  includes rotators  450  for rotating a media  427  in a direction, as indicated by arrow  428 . In an embodiment, media  427  is magnetic tape. In an alternative embodiment, media  427  is sputtered magnetic tape. It is noted that media  427  may be nearly any alternative flexible media enabled to store data thereon and to which data can be written and from which data can be read.  
         [0040]     Tester  400  also includes a writer  410  for writing data to media  427 . Writer  410  is for writing a signal onto a magnetic data layer of media  427  for use as a value during the performing of test  520 , in an embodiment of the present invention. It is noted that writer  410  can write a single signal or a plurality of signals having similar or varying values, thus providing a range of values. Tester  400  further includes a cartridge  405  for receiving a slider  300 . Slider  300  is oriented in a testing position allowing tester  400  to perform test  520  thereon when slider  300  is removably received in cartridge  405 . When slider  300  is disposed in cartridge  405 , thus in a testing position, ABS surface  320 , analogous to ABS  320  of  FIG. 3 , faces a magnetic data layer of media  427 .  
         [0041]     Tester  400  additionally includes one or more large data collector/analyzer(s)  475  that is/are communicatively coupled therewith for collecting and analyzing data generated during test  520 , in an embodiment of the present invention.  
         [0042]     Continuing with  FIG. 4 , in an embodiment of the present invention, a slider  300  is deposited in cartridge  405  subsequent to wafer and slider fabrication, as described in  FIG. 3 . In an embodiment, cartridge  405  is configured to receive an individual slider  300 . In another embodiment, cartridge  405  can be configured to receive multiple sliders  300 , e.g., a slider bar.  
         [0043]     Once a slider  300  is properly disposed in cartridge  405 , rotators  450  rotate media  427  and write device  410  writes a signal onto the magnetic data layer of media  427 . Rotators  450  rotate media  427  so the field of media  427  having the signal written thereon is moved past slider  300  and read sensor  306 . Read sensor  306  of slider  300  detects the signal on media  427  as the field of media  427 , onto which the signal was written, is moved past slider  300 . In an embodiment of the present invention, media  427  is moved in a right to left direction, as indicated by arrow  428 .  
         [0044]     Still referring to  FIG. 4 , as the field of media  427  having the signal written thereon moves past read sensor  306  of slider  300 , as indicated by arrow  428 , read sensor  306  detect the value of the signal written, in an embodiment of the present invention. An advantage of read sensor  306  detecting the signal written by write device  410  is that it enables data collector/analyzer  475  to compare the value of the signal written by writer  410  to the values sensed by read sensor  306  of slider  300 . This provides more thorough and accurate data for assessing the characteristics of slider  300 .  
         [0045]     In one embodiment, media  427  may be rotated past surface  320  of slider  300  in a non-flying position. In an alternative embodiment, media  427  may be rotated past surface  320  of slider  300  in a flying position. Regardless of the flying position, it is noted that slider  300  remains statically positioned while the field of media  427  having the signal written thereon is motioned past slider  300 . Tester  400  enables proper characterizing (testing) of slider  300  by combining a quasi-static test (QST) and a dynamic electrical test (DET) into a single test process, e.g., test  520 . Further, tester  400  enables characterization of slider  300  while obviating the need for assembling a head gimble assembly prior to performing a DET test, as described herein with reference to head assembly step  14  and test  15  of  FIG. 1A , in accordance with an embodiment of the present invention.  
         [0046]      FIG. 5  is a flowchart  500  of a process for steps performed in accordance with one embodiment of the present invention for assessing the characteristics of a slider  300 . Flowchart  500  includes processes of the present invention which, in one embodiment, are carried out by fabrication and processing devices and components under the control of computer readable and computer executable instructions. The computer readable and computer executable instructions enable the fabrication, processing, and testing of a slider, e.g., slider  300 . The computer readable and computer executable instructions may reside in any type of computer readable medium. Although specific steps are disclosed in flowchart  500 , such steps are exemplary. That is, the present invention is well suited to performing various other steps or variations of the steps recited in  FIG. 5 . Within the present embodiment, it should be appreciated that the steps of flowchart  500  may be performed by software, by hardware or by any combination of software and hardware for assessing the characteristics of a slider  300 , in an embodiment of the present invention.  
         [0047]     In step  505  of  FIG. 5 , a wafer fabrication process  505  is performed, forming multiple read/write devices, e.g., read/write device  305 , in each of which is disposed a read sensor  306 , of  FIG. 4 , in an embodiment of the present invention. Subsequent to wafer fabrication  505 , flowchart  500  proceeds to step  515 .  
         [0048]     Step  515  is a slider fabrication process  510  that is performed upon the wafer containing read/write device  305 , in an embodiment of the present invention. In slider fabrication  515 , individual read/write devices  305  are sliced and lapped, creating a slider  300  ( FIG. 3 ). Alternatively, multiple read/write devices  305  are sliced and lapped together, creating a slider bar. In an embodiment, a slider bar is a collection of sliders  300 . Subsequent to slider fabrication process  515 , the flowchart proceeds to step  520  for testing the characteristics of slider  300 .  
         [0049]     Referring to step  520 , a slider level dynamic magnetic test  520  is performed on slider  300  ( FIG. 3 ) through utilization of a tester, e.g., tester  400 , as described herein with reference to  FIG. 4 , in an embodiment of the present invention. In slider level dynamic magnetic test  520 , the tests conventionally implemented in a plurality of tests, e.g., a QST and a DET, as described in  FIG. 1A , are combined. It is noted that slider level dynamic magnetic test  520  does not require a head gimble assembly to be assembled prior to having slider  300  characteristically assessed. Thus slider level dynamic magnetic test  520  can obviate the need for a head assembly  14  for use in a test  15 , as described in  FIG. 1A . Therefore, upon a slider  300  having a dissatisfactory assessment, embodiments of the present invention enable a slider  300  to be discarded, e.g., disposal  555 , obviating the need for assembly of and/or discarding a head gimble assembly as in conventional assessing processes.  
         [0050]     Still referring to step  520 , slider level dynamic magnetic test  520  can, in an embodiment, include testing slider  300  for amplitude, asymmetry, and stability. Further, test  520  can include testing slider  300  for track average amplitude (TAA), comparison to bias, and track average amplitude asymmetry. It is noted that because shields, e.g., magnetic shields  308  of  FIG. 3 , present in slider  300  are not saturated in a uniform environment, data collected during test  520  will have a greater correlation to real-time values than a convention static test, e.g., test  13  of  FIG. 1A .  
         [0051]     For example, once slider  300  is oriented in cartridge  405  of tester  400 , writer  410  writes a signal to media  427  having a value of 4. Rotators  450  cause media  427  to move in the direction of arrow  428 . As the signal written on media  427  is moved past slider  300 , via rotators  450 , read sensor  306  of slider  300  detects a 3.5 value. This discrepancy can indicate an incorrect calibration for writer  410  or the field onto which the signal was written may have a defect. As such, the signal can be re-written by writer  410  and/or writer  410  may be recalibrated, in an embodiment of the present invention. In another embodiment, this discrepancy can also indicate a faulty read sensor  306 , and as such, read sensor  306  can be rejected, while obviating the need for an HGA process, as described in  FIG. 1A .  
         [0052]     In another example, using the same signal value of  4 , when the field of media  427  having the written signal is rotated past read sensor  306  and read sensor  306  detects a signal value of 4, this can indicate that read sensor  306  is fully functional and can provide proper sensing of states of data disposed on a media storage device, e.g., disk  215  of  FIG. 2A .  
         [0053]     Continuing with step  520 , it is noted that as the field of media  427  having a signal written thereon is moved past read sensor  306  of slider  300 , the movement enables data to be generated relative to most characteristics of a slider  300  that are necessary for proper characterization. It is further noted that slider  300 , once disposed in cartridge  405  is statically positioned. Further, because of a signal being written to media  427 , instead of a slider  300  being emersed in a uniform environment, as described in step  13  of  FIG. 1A , the characterization of slider  300  is more complete as the signal sensed by read sensor  306  of slider  300  is representative of real conditions, thus decreasing the dependence upon correction factors used to simulate a real signal, as described in  FIG. 1A . Thus, embodiments of the present invention can provide a reduction in read/write device fabrication and related testing costs when compared to conventional fabrication and testing methods, e.g.,  FIG. 1A .  
         [0054]     In step  530  of flowchart  500 , a head gimble assembly  225 , as described herein with reference to  FIG. 2A and 2B  is assembled, in an embodiment of the present invention. It is noted that head gimble assembly  225  is a necessary component in a completed a hard disc drive  200 , HGA  225  is not used in performing an assessment of characteristics of a read sensor  306  of slider  300  in accordance with an embodiment of the present invention. In the present embodiment, subsequent to completion of an HGA  225 , flowchart processes to step  540 .  
         [0055]     In step  540  of flowchart  500 , the head gimble assembly  225  is assembled in a head stack assembly, in an embodiment of the present invention. Subsequent thereto, flowchart  500  proceeds to step  550 .  
         [0056]     In step  550  of flowchart  500 , the head stack assembly is assembled into a hard disc assembly (HDA) in an embodiment of the present invention. Subsequent thereto, flowchart  500  proceeds to step  560 .  
         [0057]     In step  560  of flowchart  500 , a final test  560  is performed on the HDA in an embodiment of the present invention. If the HDA fails test  560 , flowchart  500  may proceed to disposal  555 . Alternatively, flowchart  500  may return to Test  520 , HGA  530 , HSA  540 , or HDA  550 , depending upon the faults found during final testing  560 . If the HDA being tested passes, the flowchart proceeds to step  570 , the delivery of the HDA for utilization as a hard disc drive.  
         [0058]     Advantageously, embodiments of the present invention provide for improved characterization of a fabricated read/write device in a slider and/or a slider bar. Further, embodiments also provide a testing apparatus for providing a more complete and thorough assessing of the characteristics of a fabricated read/write device in a slider and/or a bar slider. Additionally, embodiments provide a method for assessing the characteristics of a fabricated read sensor in a slider and/or a bar slider in which conventional testing processes are combined into a single test, thus reducing testing time. Also, embodiments of the present invention further provide for obviation of an assembly process utilized during a conventional testing process.  
         [0059]     The foregoing descriptions of specific embodiments of the present invention have been presented for purposes of illustration and description. They are not intended to be exhaustive or to limit the invention to the precise forms disclosed, and many modifications and variations are possible in light of the above teaching. The embodiments were chosen and described in order to best explain the principles of the invention and its practical application, to thereby enable others skilled in the art to best utilize the invention and various embodiments with various modifications as are suited to the particular use contemplated. It is intended that the scope of the invention be defined by the Claims appended hereto and their equivalents.