Magnetic recording write transducer having an improved sidewall angle profile

Information

  • Patent Grant
  • 9343086
  • Patent Number
    9,343,086
  • Date Filed
    Thursday, October 10, 2013
    11 years ago
  • Date Issued
    Tuesday, May 17, 2016
    8 years ago
Abstract
A method and system provide a magnetic transducer having an air-bearing surface (ABS). The magnetic transducer includes a main pole and at least one coil for energizing the main pole. The main pole includes a pole tip region and a yoke region. The pole tip region includes sidewalls, a bottom and a top wider than the bottom. At least one of the sidewalls forms a first sidewall angle with a down track direction at the ABS and a second sidewall angle with the down track direction at a first distance recessed from the ABS. The first sidewall angle is greater than the second sidewall angle.
Description
BACKGROUND


FIGS. 1A, 1B and 1C depict ABS, yoke and side views of a conventional magnetic recording head 10. The magnetic recording transducer 10 may be a perpendicular magnetic recording (PMR) head. The conventional magnetic recording transducer 10 may be a part of a merged head including the write transducer 10 and a read transducer (not shown). Alternatively, the magnetic recording head may be a write head including only the write transducer 10. Although termed a yoke view, the view shown in FIG. 1B is taken along the surface parallel to the ABS a distance x1 from the ABS. This surface is depicted as a dotted line in FIG. 1C.


The main pole 20 resides on an underlayer 12 and includes sidewalls 22 and 24. The sidewalls 22 and 24 of the conventional main pole 20 form an angle α0 with the down track direction at the ABS and an angle α1 with the down track direction at the distance x1 from the ABS. As can be seen in FIGS. 1A and 1B, portions of the main pole 20 recessed from the ABS in the stripe height direction are wider in the cross track direction than at the ABS. In addition, the angle between the sidewalls 22 and 24 and the down track direction increases. Thus, α1 is greater than α0. For example, if α0 is on the order of 13°, then α1 may be 25°.


Although the conventional magnetic recording head 10 functions, there are drawbacks. In particular, the conventional magnetic recording head 10 may not perform sufficiently at higher recording densities. For example, the write field of the conventional main pole 20 may not have a sufficiently high magnitude write field to meet particular standards. Accordingly, what is needed is a system and method for improving the performance of a magnetic recording head.





BRIEF DESCRIPTION OF SEVERAL VIEWS OF THE DRAWINGS


FIGS. 1A-1C depict ABS, yoke and side view of a conventional magnetic recording head.



FIG. 2 depicts an exemplary embodiment of a magnetic recording disk drive.



FIGS. 3A, 3B and 3C depict ABS, yoke and side views of an exemplary embodiment of a magnetic recording transducer.



FIGS. 4A, 4B and 4C depict ABS, yoke and side views of an exemplary embodiment of a magnetic recording transducer.



FIGS. 5A, 5B, 5C, 5D and 5E depict ABS and various views and a side view of an exemplary embodiment of a magnetic recording transducer.



FIGS. 6A, 6B, 6C, 6D and 6E depict ABS and various views and a side view of an exemplary embodiment of a magnetic recording transducer.



FIG. 7 depicts a flow chart of an exemplary embodiment of a method for providing magnetic recording transducer.



FIG. 8 depicts a flow chart of an exemplary embodiment of a method for fabricating a portion of a magnetic recording transducer.





DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS


FIG. 2 depicts a side view of an exemplary embodiment of a portion of a disk drive 100 including a write transducer 120. FIGS. 3A, 3B and 3C depict ABS, yoke and side views of the transducer 120. For clarity, FIGS. 2, 3A, 3B and 3C are not to scale. For simplicity not all portions of the disk drive 100 and transducer 120 are shown. In addition, although the disk drive 100 and transducer 120 are depicted in the context of particular components other and/or different components may be used. For example, circuitry used to drive and control various portions of the disk drive 100 is not shown. For simplicity, only single components 102, 110, 120 and 130 are shown. However, multiples of each components 102, 110, 120 and/or and their sub-components, might be used. The disk drive 100 may be a PMR disk drive. However, in other embodiments, the disk drive 100 may be configured for other types of magnetic recording.


The disk drive 100 includes media 102, a slider 110 and a write transducer 120. Additional and/or different components may be included in the disk drive 100. Although not shown, the slider 110 and thus the transducer 120 are generally attached to a suspension (not shown).


The transducer 120 is fabricated on the slider 110 and includes an air-bearing surface (ABS) proximate to the media 102 during use. In general, the disk drive 100 includes a write transducer 120 and a read transducer (not shown). However, for clarity, only the write transducer 120 is shown. The transducer 120 includes a main pole 130 and coils 140. In other embodiments, different and/or additional components may be used in the write transducer 120.


The coil(s) 140 are used to energize the main pole 130. Two turns 140 are depicted in FIG. 2. Another number of turns may, however, be used. Note that only a portion of the coil(s) 140 is shown in FIG. 2. If, for example, the coil(s) 140 form a helical coil, then additional portion(s) of the coil(s) 140 may be located on the opposite side of the main pole 130 as is shown. If the coil(s) 140 is a spiral, or pancake, coil, then additional portions of the coil(s) 140 may be located further from the ABS. Further, additional coils may also be used.


The main pole 130 includes a pole tip region 132 close to the ABS and a yoke region 134 recessed from the ABS. The pole tip region 132 is shown as having top and bottom bevels 131 and 133, respectively, near the ABS. In addition, the pole tip region 134 includes sidewalls 136 and 138 in the cross track direction. The sidewalls are configured such that the pole 130 has a bottom and a top wider than the bottom.


The sidewalls 136 and 138 form sidewall angles with the down track direction. At the ABS, the sidewall 136 forms sidewall angle α0 with respect to the down track direction. In some embodiments, the sidewalls 136 and 138 are symmetric. Thus, although not labeled, the sidewall 138 would form substantially the same sidewall angle with the down track direction as the sidewall 136. In some embodiments, α0 is not more than fourteen degrees. In some such embodiments, α0 is at least twelve degrees. For example, α0 may be nominally 13.5°. At a distance x1 recessed from the ABS, the sidewall 136 forms sidewall angle α1 with the down track direction. The sidewall angle α1 is less than α0 at x1. For example, if α0 is 12-14 degrees, then α1 is greater than or equal to zero degrees and not more than 12-14 degrees. In some embodiments, α1 is at least seven degrees. Further, the distance x1 may vary. In some embodiments, x1 is desired to be not more than the distance which the bevel 131 or 133 extends into the ABS. For example, in some embodiments, x1 is not more than two hundred nanometers. In some embodiments, x1 is desired to be closer to the ABS. In some embodiments, x1 may be not more than eighty nanometers. For example, x1 may be at least 30 nm from the ABS if, for example, the processing tolerance in the location of x1 is 10 nm (corresponding to a 3σ of 30 nm). In general, x1 is desired to be sufficiently large that the sidewall angle α0 at the ABS remains unchanged. The manner in which the sidewall angle changes from α0 to α1 may vary. The sidewall angle may monotonically decrease between the ABS and x1. In some embodiments, the sidewall angle smoothly varies from α0 to α1. In other embodiments, the sidewall angle may change in step function(s) from α0 to α1. Although described herein as step function(s), one of ordinary skill in the art will recognize that there are processing and/or other limitations or considerations. Therefore, the transitions of such a “step” function may be rounded and/or transitions may not be sharp. Thus, as used herein, a step function may not be identical to a purely mathematical step function. This may occur at x1 or between the ABS and x1. In other embodiments, the change may be linear or piece-wise linear. In other embodiments the change may be in accordance with a higher order function including but not limited to a quadratic function. However, other configurations are possible. Although described herein in terms of particular mathematical functions, one of ordinary skill in the art will recognize that there are processing and/or other limitations or considerations. Consequently, the actual profile of the main poles may not precisely follow the mathematical functions used herein.


The magnetic disk drive 100 may exhibit improved performance. Because of the variation in the sidewall angle, the magnetic field generated by the main pole 130 and used to write to the media 102 may be enhanced. The reverse overwrite gain may also be improved. The gradient in the magnetic field may also be improved while maintaining substantially the same side fields. As a result, adjacent track interference may not be adversely affected. Further, the pole tip region 132 of the main pole 130 may have an increased magnetic volume. Stated differently, the pole tip region 132 may include more magnetic material. As a result, the cross track magnetic anisotropy may be improved and domain lockup issues mitigated. Thus, performance of the disk drive 100 may be improved.



FIGS. 4A, 4B and 4C depict ABS, yoke and side views of a transducer 120′ analogous to the transducer 120 in disk drive 100. For clarity, FIGS. 4A, 4B and 4C are not to scale. For simplicity not all portions of the transducer 120′ are shown. Because the magnetic recording transducer 120′ is analogous to the transducer 120 in the magnetic disk drive 100, analogous components have similar labels.


The transducer 120′ includes a main pole 130′ having sidewalls 136′ and 138′ that are analogous to the main pole 130 and sidewalls 136 and 138, respectively. The main pole 130′ also includes a pole tip region 132′ and a yoke region 134′ that are analogous to the pole tip 132 and yoke 134, respectively. The pole tip region 132′ is shown as having top and bottom bevels 131 and 133, respectively that are analogous to the bevels 131 and 133 depicted in FIGS. 2 and 3C. The sidewalls 136′ and 138′ are configured such that the pole 130′ has a bottom and a top wider than the bottom.


The sidewalls 136′ and 138′ form sidewall angles α0′ and α1′ with respect to the down track direction at the ABS and x1′, respectively. In some embodiments, α0′ has a size range analogous to α0. For example, α0′ may be at least twelve degrees and not more than fourteen degrees and in some embodiments may be nominally 13.5°. The sidewall angle α1′ is less than α0′ at x1′. In the embodiment shown, α1′ is zero degrees. The distance x1′ may also vary in a manner analogous to x1. In some embodiments, x1′ is desired to be not more than the distance which the bevel 131 or 133 extends into the ABS. For example, in some embodiments, x1′ is not more than two hundred nanometers. In some embodiments, x1′ is desired to be closer to the ABS. In some embodiments, x1′ is not more than eighty nanometers. For example, x1′ may be at least 30 nm from the ABS if, for example, the processing tolerance in location of x1′ is 10 nm. In general, x1′ is desired to be sufficiently large that the sidewall angle α0′ at the ABS remains unchanged. The manner in which the sidewall angle changes from α0′ to α1′ may vary. The sidewall angle may monotonically decrease between the ABS and x1′. In some embodiments, the sidewall angle smoothly varies from α0′ to α1′. In other embodiments, the sidewall angle may change in step function(s) from α0′ to α1′. These change(s) may occur at x1′ or between the ABS and x1′. In other embodiments, the change may be linear or piece-wise linear. In other embodiments the change may be in accordance with a higher order function including but not limited to a quadratic function. However, other configurations are possible. Although the variation in sidewall angle is described herein in terms of step function(s) and other mathematical functions, one of ordinary skill in the art will recognize that there exist processing and/or other limitations or considerations. Therefore, the transitions of such a “step” function may be rounded and/or transitions may not be sharp. Similarly, “linear” regions may not be perfectly straight. Thus, the actual profile of the main poles may not precisely follow the mathematical functions used herein.


The magnetic transducer 120′ may exhibit improved performance for analogous reasons to those discussed above. Because of the variations in the sidewall angle, the magnetic field generated by the main pole 130′ may be increased. The reverse overwrite gain may also be improved. The gradient in the magnetic field may also be improved while maintaining substantially the same side fields. As a result, adjacent track interference may not be adversely affected. Further, the pole tip region 132′ of the main pole 130′ may have an increased magnetic volume. As a result, the cross track magnetic anisotropy may be improved and domain lockup issues mitigated. Thus, performance of the disk drive 100 may be improved.



FIGS. 5A, 5B, 5C and 5E depict ABS, first pole tip, second pole tip, yoke and side views, respectively, of a transducer 120″ analogous to the transducers 120/120′ and disk drive 100. For clarity, FIGS. 5A-5E are not to scale. For simplicity not all portions of the transducer 120″ are shown. Because the magnetic recording transducer 120″ is analogous to the transducers 120/120′ in the magnetic disk drive 100, analogous components have similar labels.


The transducer 120″ includes a main pole 130″ having sidewalls 136″ and 138″ that are analogous to the main pole 130/130′ and sidewalls 136/136′ and 138/138′, respectively. The main pole 130″ also includes a pole tip region 132″ and a yoke region 134″ that are analogous to the pole tip 132/132′ and yoke 134/134′, respectively. The pole tip region 132″ is shown as having top and bottom bevels 131 and 133, respectively, that are analogous to the bevels 131 and 133 depicted in FIGS. 2, 3C and 4C. The sidewalls 136″ and 138″ are configured such that the pole 130″ has a bottom and a top wider than the bottom.


The sidewalls 136″ and 138″ form sidewall angles α0″ and α1″ with respect to the down track direction at the ABS and x1″, respectively. In addition, the sidewalls 136″ and 138″ form sidewall angles α2 and α3 at positions x2 and x3. In the embodiment shown, α2 and α3 are between α0 and α1. Thus, the sidewall angle monotonically decreases from the ABS to x2, x3 and x1. In some embodiments, α0″ has a size range analogous to α0. For example, α0″ may be at least twelve degrees and not more than fourteen degrees and in some embodiments may be nominally 13.5°. The sidewall angle α1″ is less than α0″ at x1″. In the embodiment shown, α1″ is zero degrees. The distance x1″ may also vary in a manner analogous to x1/x1′. In some embodiments, x1″ is desired to be not more than the distance which the bevel 131 or 133 extends into the ABS. For example, in some embodiments, x1″ is not more than two hundred nanometers. In some embodiments, x1″ is desired to be closer to the ABS as described above. In general, x1″ is desired to be sufficiently large that the sidewall angle α0″ at the ABS remains unchanged. The manner in which the sidewall angle changes from α0″ to α1″ may vary. In some embodiments, the sidewall angle smoothly varies from α0′ to α1′. In other embodiments, the sidewall angle may change in a manner analogous to step function(s) from α0″ to α1″. These change(s) may occur at x2, x3 and x1″. For example, α2 may be 11° and x2 may be approximately 50 nm within tolerances. Similarly, α3 may be 7° and x3 may be one hundred nanometers within tolerances. However, in other embodiments, other distances and other sidewall angles may be possible. In other embodiments, the change may be linear or piece-wise linear. For example, a new slope for each line segment may occur at x2, x3 and x1. In other embodiments the change may be in accordance with a higher power function including but not limited to a quadratic function. However, other configurations are possible. Although the variation in sidewall angle is described herein in terms of step function(s) and other mathematical functions, one of ordinary skill in the art will recognize that there exist processing and/or other limitations or considerations. Therefore, the transitions of such a “step” function may be rounded and/or transitions may not be sharp. Similarly, “linear” regions may not be perfectly straight. Thus, the actual profile of the main poles may not precisely follow the mathematical functions used herein.


The magnetic transducer 120″ may exhibit improved performance for analogous reasons to those discussed above. Because of the variations in the sidewall angle, the magnetic field generated by the main pole 130″ may be increased. The reverse overwrite gain may also be improved. The gradient in the magnetic field may also be improved while maintaining substantially the same side fields. As a result, adjacent track interference may not be adversely affected. Further, the pole tip region 132″ of the main pole 130″ may have an increased magnetic volume. As a result, the cross track magnetic anisotropy may be improved and domain lockup issues mitigated. Thus, performance of the disk drive 100 may be improved.



FIGS. 6A, 6B, 6C, 6D and 6E depict ABS, first pole tip, second pole tip, yoke and side views, respectively, of a transducer 120′″ analogous to the transducers 120/120′/120″ and disk drive 100. For clarity, FIGS. 6A-6E are not to scale. For simplicity not all portions of the transducer 120′″ are shown. Because the magnetic recording transducer 120′″ is analogous to the transducers 120/120′/120″ in the magnetic disk drive 100, analogous components have similar labels.


The transducer 120′″ includes a main pole 130′″ having sidewalls 136′″ and 138′″ that are analogous to the main pole 130/130′/130″ and sidewalls 136/136′/136″ and 138/138′/138″, respectively. The main pole 130′″ also includes a pole tip region 132′″ and a yoke region 134′″ that are analogous to the pole tip 132/132′/132″ and yoke 134/134′/134″, respectively. The pole tip region 132′″ is shown as having top and bottom bevels 131 and 133, respectively, that are analogous to the bevels 131 and 133 depicted in FIGS. 2, 3C, 4C and 5C. The sidewalls 136′″ and 138′″ are configured such that the pole 130′″ has a bottom and a top wider than the bottom.


The sidewalls 136′″ and 138′″ form sidewall angles α0′″ and α1′″ with respect to the down track direction at the ABS and x1′″, respectively. In addition, the sidewalls 136′″ and 138′″ form sidewall angles α2′ and α3′ at positions x2′ and x3′. In the embodiment shown, α2′ and α3′ are substantially equal to α0′″. Thus, the sidewall angle is substantially constant from the ABS to x2 and at least x3. In some embodiments, α0′″ has a size range analogous to α0. For example, α0′″ may be at least twelve degrees and not more than fourteen degrees and in some embodiments may be nominally 13.5°. The sidewall angle α1′″ is less than α0′″ at x1′″. In the embodiment shown, α1′″ is zero degrees. The distance x1′″ may vary in a manner analogous to x1/x1′/x1″. In some embodiments, x1′″ is desired to be not more than the distance which the bevel 131 or 133 extends into the ABS. For example, in some embodiments, x1′″ is not more than two hundred nanometers. In some embodiments, x1′″ is desired to be closer to the ABS as described above. In general, x1′″ is desired to be sufficiently large that the sidewall angle αO′″ at the ABS remains unchanged. The manner in which the sidewall angle changes from α0′″ to α1′″ may vary. In some embodiments, the sidewall angle may change in a step function from α0′″ to α1′″ at some location after x3′ and by x1′″. However, other configurations are possible. Although the variation in sidewall angle is described herein in terms of step function(s) and other mathematical functions, one of ordinary skill in the art will recognize that there exist processing and/or other limitations or considerations. Therefore, the transitions of such a “step” function may be rounded and/or transitions may not be sharp. Similarly, “linear” regions may not be perfectly straight. Thus, the actual profile of the main poles may not precisely follow the mathematical functions used herein.


The magnetic transducer 120′″ may exhibit improved performance for analogous reasons to those discussed above. Because of the variations in the sidewall angle, the magnetic field generated by the main pole 130′″ may be increased. The reverse overwrite gain may also be improved. The gradient in the magnetic field may also be improved while maintaining substantially the same side fields. As a result, adjacent track interference may not be adversely affected. Further, the pole tip region 132′″ of the main pole 130′″ may have an increased magnetic volume. As a result, the cross track magnetic anisotropy may be improved and domain lockup issues mitigated. Thus, performance of the disk drive 100 may be improved.



FIG. 7 depicts an exemplary embodiment of a method 300 for providing a magnetic recording transducer 120 having a main pole that may has a varying sidewall angle, such as main pole 130, 130′, 130″, and/or 130′″. For simplicity, some steps may be omitted, interleaved, and/or combined. The method 200 is also described in the context of providing a magnetic recording head 100 and transducer 120 depicted in FIGS. 2, 3A, 3B and 3C. However, the method 200 may be used to fabricate multiple magnetic recording heads at substantially the same time. The method 200 may also be used to fabricate other magnetic recording transducers including but not limited to any combination of 120, 120′, 120″, and/or 120′″. The method 200 is also described in the context of particular layers. A particular layer may include multiple materials and/or multiple sub-layers. The method 200 also may start after formation of other portions of the magnetic recording head. For example, the method 200 may start after a read transducer, return pole/shield and/or other structure have been fabricated.


Referring to FIGS. 2, 3A-3C and 7, the main pole 130 is provided, via step 202. Step 202 may include using one or more damascene processes. For example, a trench may be formed in a layer. The trench may be fabricated such that portions of the trench sidewalls form different angles with the down track direction. The material(s) for the pole 130 deposited, for example via plating. One or more ferromagnetic materials may be used. The pole tip 132 and yoke 134 may be formed. Other methods may also be used to form the pole 130 including but not limited to full film deposition of magnetic materials and removal for example via milling and/or lapping.


The coil(s) 140 are provided, via step 204. Portions of step 204 may thus be interleaved with the remaining steps of the method 200. For example, portions of the coil 140 may be provided before the formation of the main pole 130. However, other portions of the coil 140 may be provided after some or all of the main pole 130 has been formed. Step 204 may also include depositing and patterning the material(s) used for the coil(s) 140. Step 204 may include forming a single helical coil or one or more pancake/spiral coil. In such embodiments, a pancake coil 140 may include other turns far from the ABS.


Using the method 200, the magnetic disk drive 100 and magnetic transducers 120, 120′, 120″ and/or 120′″ may be provided. Thus, the benefits of the magnetic transducers 120, 120′, 120″ and/or 120′″ may be achieved.



FIG. 8 depicts an exemplary embodiment of a method 210 for providing a magnetic recording transducer 120 having a main pole that may has a varying sidewall angle, such as main pole 130, 130′, 130″, and/or 130′″. For simplicity, some steps may be omitted, interleaved, and/or combined. The method 210 is also described in the context of providing a magnetic recording head 100 and transducer 120 depicted in FIGS. 2, 3A, 3B and 3C. However, the method 210 may be used to fabricate multiple magnetic recording heads at substantially the same time. The method 210 may also be used to fabricate other magnetic recording transducers including but not limited to any combination of 120, 120′, 120″, and/or 120′″. The method 210 is also described in the context of particular layers. A particular layer may include multiple materials and/or multiple sub-layers. The method 210 also may start after formation of other portions of the magnetic recording head. For example, the method 210 may start after a read transducer, return pole/shield and/or other structure have been fabricated.


Referring to FIGS. 2, 3A-3C and 8, materials are provided in layers that are perpendicular to the ABS, via step 212. For example, one material may extend from the ABS to x1, while another extends from x1 to further from the ABS. In other embodiments, such as the transducer 120″, one material may extend from the ABS to x2, another from x2 to x3, a third from x3 to x1 and a fourth from x1 to further from the ABS.


A trench is etched for the pole, via step 204. Step 204 may include using one or more damascene processes. The different materials may have different etch characteristics. Consequently, each material may etch a different amount and provide a portion of the trench that has a different profile. Thus, the trench may have different sidewall angles at different distances from the ABS. The material(s) for the pole 130 deposited, via step 216. One or more ferromagnetic materials may be plated. The pole tip 132 and yoke 134 may be formed.


Using the method 210, the main pole 130/130′/130″/130′″, magnetic disk drive 100 and magnetic transducers 120, 120′, 120″ and/or 120′″ may be provided. Thus, the benefits of the magnetic transducers 120, 120′, 120″ and/or 120′″ may be achieved.

Claims
  • 1. A magnetic transducer having air-bearing surface (ABS) comprising: a main pole including a pole tip region and a yoke region, the pole tip region including a plurality of sidewalls, a bottom surface, and a top surface wider than the bottom surface, the plurality of sidewalls being between the top surface and the bottom surface, the top surface being opposite to the bottom surface and in a down track direction from the bottom surface, at least one of the plurality of sidewalls forming a first sidewall angle with a down track direction at the ABS and a second sidewall angle with the down track direction at a first distance recessed from the ABS in a yoke direction perpendicular to the ABS, the first sidewall angle being greater than the second sidewall angle, the down track direction being parallel to the ABS and perpendicular to the yoke direction, the first sidewall angle and the second sidewall angle being formed by the at least one of the plurality of sidewalls at the bottom surface of the main pole; andat least one coil for energizing the main pole.
  • 2. The magnetic transducer of claim 1 wherein the second sidewall angle is zero degrees.
  • 3. The magnetic transducer of claim 1 wherein the plurality of sidewalls form a third sidewall angle with the down track direction at a second distance recessed from the ABS, the second distance being less than the first distance and the third sidewall angle being greater than the second sidewall angle.
  • 4. A magnetic transducer having air-bearing surface (ABS) comprising: a main pole including a pole tip region and a yoke region, the pole tip region including a plurality of sidewalls, a bottom surface, and a top surface wider than the bottom surface, the plurality of sidewalls being between the top surface and the bottom surface, the top surface being opposite to the bottom surface and in a down track direction from the bottom surface, at least one of the plurality of sidewalls forming a first sidewall angle with a down track direction at the ABS and a second sidewall angle with the down track direction at a first distance recessed from the ABS in a yoke direction perpendicular to the ABS, the first sidewall angle being greater than the second sidewall angle, the down track direction being parallel to the ABS and perpendicular to the yoke direction, wherein the plurality of sidewalls form a third sidewall angle with the down track direction at a second distance recessed from the ABS, the second distance being less than the first distance and the third sidewall angle being greater than the second sidewall angle and wherein the plurality of sidewalls form a fourth sidewall angle with the down track direction at a third distance recessed from the ABS, the third distance being less than the first distance and the fourth sidewall angle being greater than the second sidewall angle; andat least one coil for energizing the main pole.
  • 5. The magnetic transducer of claim 1 wherein the plurality of sidewalls form the first sidewall angle between the ABS and the first distance.
  • 6. The magnetic transducer of claim 1 wherein the plurality of sidewalls form a sidewall angle with the down track direction that substantially monotonically decreases between the first sidewall angle and the second sidewall angle.
  • 7. The magnetic transducer of claim 1 wherein the plurality of sidewalls form a sidewall angle with the down track direction that substantially linearly decreases between the first sidewall angle and the second sidewall angle.
  • 8. The magnetic transducer of claim 1 wherein the plurality of sidewalls form a sidewall angle with the down track direction that decreases between the first sidewall angle and the second sidewall angle in accordance with a piecewise linear manner.
  • 9. The magnetic transducer of claim 1 wherein the plurality of sidewalls form a sidewall angle with the down track direction that decreases between the first sidewall angle and the second sidewall angle in accordance with at least one step function.
  • 10. The magnetic transducer of claim 1 wherein the plurality of sidewalls form a sidewall angle with the down track direction that decreases between the first sidewall angle and the second sidewall angle in accordance with a function having a power greater than one.
  • 11. The magnetic transducer of claim 1 wherein the first sidewall angle is at least eleven degrees and not more than fifteen degrees.
  • 12. The magnetic transducer of claim 1 wherein the first distance is greater than zero and not more than two hundred nanometers.
  • 13. The magnetic transducer of claim 12 wherein the first distance is at least ten nanometers and not more than one hundred nanometers.
  • 14. The magnetic transducer of claim 12 wherein the first distance is at least thirty nanometers and not more than eighty nanometers.
  • 15. The magnetic transducer of claim 1 wherein the main pole further includes a bevel extending a bevel distance from the ABS, the first distance being less than or equal to the bevel distance.
  • 16. A disk drive comprising: a magnetic recording medium,a slider, anda magnetic transducer coupled with the slider, the magnetic transducer having air-bearing surface (ABS), a main pole and at least one coil for energizing the main pole, the main pole including a pole tip region and a yoke region, the pole tip region including a plurality of sidewalls, a bottom surface, and a top surface wider than the bottom surface, the plurality of sidewalls being between the top surface and the bottom surface, the top surface being opposite to the bottom surface and in a down track direction from the bottom surface, the magnetic recording medium moving in the down track direction with respect to the magnetic transducer, at least one of the plurality of sidewalls forming a first sidewall angle with a down track direction at the ABS and a second sidewall angle with the down track direction at a first distance recessed from the ABS in a yoke direction perpendicular to the ABS, the first sidewall angle being greater than the second sidewall angle, the down track direction being parallel to the ABS and perpendicular to the yoke direction, the first sidewall angle and the second sidewall angle being formed by the at least one of the plurality of sidewalls at the bottom surface of the main pole.
  • 17. A method for fabricating magnetic transducer having air-bearing surface (ABS) comprising: providing a main pole including a pole tip region and a yoke region, the pole tip region including a plurality of sidewalls, a bottom surface, and a top surface wider than the bottom surface, the plurality of sidewalls being between the top surface and the bottom surface, the top surface being opposite to the bottom surface and in a down track direction from the bottom surface, at least one of the plurality of sidewalls forming a first sidewall angle with a down track direction at the ABS and a second sidewall angle with the down track direction at a first distance recessed from the ABS in a yoke direction perpendicular to the ABS, the first sidewall angle being greater than the second sidewall angle, the down track direction being parallel to the ABS and perpendicular to the yoke direction, the first sidewall angle and the second sidewall angle being formed by the at least one of the plurality of sidewalls at the bottom surface of the main pole; andproviding at least one coil for energizing the main pole.
  • 18. The method of claim 17 wherein the second sidewall angle is zero degrees.
  • 19. The method of claim 17 wherein the step of providing the main pole further includes: configuring the plurality of sidewalls to form a third sidewall angle with the down track direction at a second distance recessed from the ABS, the second distance being less than the first distance and the third sidewall angle being greater than the second sidewall angle.
  • 20. A method for fabricating magnetic transducer having air-bearing surface (ABS) comprising: providing a main pole including a pole tip region and a yoke region, the pole tip region including a plurality of sidewalls, a bottom surface, and a to surface wider than the bottom surface, the plurality of sidewalls being between the to surface and the bottom surface, the top surface being opposite to the bottom surface and in a down track direction from the bottom surface, at least one of the plurality of sidewalls forming a first sidewall angle with a down track direction at the ABS and a second sidewall angle with the down track direction at a first distance recessed from the ABS in a yoke direction perpendicular to the ABS, the first sidewall angle being greater than the second sidewall angle, the down track direction being parallel to the ABS and perpendicular to the yoke direction wherein the step of providing the main pole further includes configuring the plurality of sidewalls to form a third sidewall angle with the down track direction at a second distance recessed from the ABS, the second distance being less than the first distance and the third sidewall angle being greater than the second sidewall angle; andconfiguring plurality of sidewalls to form a fourth sidewall angle with the down track direction at a third distance recessed from the ABS, the third distance being less than the first distance and the fourth sidewall angle being greater than the second sidewall angle; andproviding at least one coil for energizing the main pole.
  • 21. The method of claim 17 wherein the plurality of sidewalls form the first sidewall angle between the ABS and the first distance.
  • 22. The method of claim 17 wherein the step of providing the main pole further includes: configuring the plurality of sidewalls to form a sidewall angle with the down track direction that substantially monotonically decreases between the first sidewall angle and the second sidewall angle.
  • 23. The method of claim 17 wherein the step of providing the main pole further includes: configuring the plurality of sidewalls to form a sidewall angle with the down track direction that substantially linearly decreases between the first sidewall angle and the second sidewall angle.
  • 24. The method of claim 17 wherein the step of providing the main pole further includes: configuring the plurality of sidewalls form a sidewall angle with the down track direction that decreases between the first sidewall angle and the second sidewall angle in accordance with a piecewise linear manner.
  • 25. The method of claim 17 wherein the step of providing the main pole further includes: configuring the plurality of sidewalls form a sidewall angle with the down track direction that decreases between the first sidewall angle and the second sidewall angle in accordance with at least one step function.
  • 26. The method of claim 17 wherein the step of providing the main pole further includes: configuring the plurality of sidewalls form a sidewall angle with the down track direction that decreases between the first sidewall angle and the second sidewall angle in accordance with a function having a power greater than one.
  • 27. The method of claim 17 wherein the step of providing the main pole further includes: providing a plurality of layers in a direction substantially perpendicular to the ABS, the plurality of materials having a plurality of removal characteristics;removing a portion of each of the plurality of layers to form a pole trench in the plurality of layers, the pole trench having a location and a profile corresponding to the main pole; andproviding at least one pole material in the pole trench.
  • 28. The method of claim 17 wherein the main pole further includes a bevel extending a bevel distance from the ABS, the first distance being less than or equal to the bevel distance.
CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims priority to provisional U.S. Patent Application Ser. No. 61/876,340, filed on Sep. 11, 2013, which is hereby incorporated by reference in its entirety.

US Referenced Citations (661)
Number Name Date Kind
5801910 Mallary Sep 1998 A
6016290 Chen et al. Jan 2000 A
6018441 Wu et al. Jan 2000 A
6025978 Hoshi et al. Feb 2000 A
6025988 Yan Feb 2000 A
6032353 Hiner et al. Mar 2000 A
6033532 Minami Mar 2000 A
6034851 Zarouri et al. Mar 2000 A
6043959 Crue et al. Mar 2000 A
6046885 Aimonetti et al. Apr 2000 A
6049650 Jerman et al. Apr 2000 A
6055138 Shi Apr 2000 A
6058094 Davis et al. May 2000 A
6073338 Liu et al. Jun 2000 A
6078479 Nepela et al. Jun 2000 A
6081499 Berger et al. Jun 2000 A
6094803 Carlson et al. Aug 2000 A
6099362 Viches et al. Aug 2000 A
6103073 Thayamballi Aug 2000 A
6108166 Lederman Aug 2000 A
6118629 Huai et al. Sep 2000 A
6118638 Knapp et al. Sep 2000 A
6125018 Takagishi et al. Sep 2000 A
6130779 Carlson et al. Oct 2000 A
6134089 Barr et al. Oct 2000 A
6136166 Shen et al. Oct 2000 A
6137661 Shi et al. Oct 2000 A
6137662 Huai et al. Oct 2000 A
6160684 Heist et al. Dec 2000 A
6163426 Nepela et al. Dec 2000 A
6166891 Lederman et al. Dec 2000 A
6172848 Santini Jan 2001 B1
6173486 Hsiao et al. Jan 2001 B1
6175476 Huai et al. Jan 2001 B1
6178066 Barr Jan 2001 B1
6178070 Hong et al. Jan 2001 B1
6178150 Davis Jan 2001 B1
6181485 He Jan 2001 B1
6181525 Carlson Jan 2001 B1
6185051 Chen et al. Feb 2001 B1
6185077 Tong et al. Feb 2001 B1
6185081 Simion et al. Feb 2001 B1
6188549 Wiitala Feb 2001 B1
6190764 Shi et al. Feb 2001 B1
6193584 Rudy et al. Feb 2001 B1
6195229 Shen et al. Feb 2001 B1
6198608 Hong et al. Mar 2001 B1
6198609 Barr et al. Mar 2001 B1
6201673 Rottmayer et al. Mar 2001 B1
6204998 Katz Mar 2001 B1
6204999 Crue et al. Mar 2001 B1
6212153 Chen et al. Apr 2001 B1
6215625 Carlson Apr 2001 B1
6219205 Yuan et al. Apr 2001 B1
6221218 Shi et al. Apr 2001 B1
6222707 Huai et al. Apr 2001 B1
6229782 Wang et al. May 2001 B1
6230959 Heist et al. May 2001 B1
6233116 Chen et al. May 2001 B1
6233125 Knapp et al. May 2001 B1
6237215 Hunsaker et al. May 2001 B1
6252743 Bozorgi Jun 2001 B1
6255721 Roberts Jul 2001 B1
6258468 Mahvan et al. Jul 2001 B1
6266216 Hikami et al. Jul 2001 B1
6271604 Frank, Jr. et al. Aug 2001 B1
6275354 Huai et al. Aug 2001 B1
6277505 Shi et al. Aug 2001 B1
6282056 Feng et al. Aug 2001 B1
6296955 Hossain et al. Oct 2001 B1
6297955 Frank, Jr. et al. Oct 2001 B1
6304414 Crue, Jr. et al. Oct 2001 B1
6307715 Berding et al. Oct 2001 B1
6310746 Hawwa et al. Oct 2001 B1
6310750 Hawwa et al. Oct 2001 B1
6317290 Wang et al. Nov 2001 B1
6317297 Tong et al. Nov 2001 B1
6322911 Fukagawa et al. Nov 2001 B1
6330136 Wang et al. Dec 2001 B1
6330137 Knapp et al. Dec 2001 B1
6333830 Rose et al. Dec 2001 B2
6340533 Ueno et al. Jan 2002 B1
6349014 Crue, Jr. et al. Feb 2002 B1
6351355 Min et al. Feb 2002 B1
6353318 Sin et al. Mar 2002 B1
6353511 Shi et al. Mar 2002 B1
6356412 Levi et al. Mar 2002 B1
6359779 Frank, Jr. et al. Mar 2002 B1
6369983 Hong Apr 2002 B1
6376964 Young et al. Apr 2002 B1
6377535 Chen et al. Apr 2002 B1
6381095 Sin et al. Apr 2002 B1
6381105 Huai et al. Apr 2002 B1
6389499 Frank, Jr. et al. May 2002 B1
6392850 Tong et al. May 2002 B1
6396660 Jensen et al. May 2002 B1
6399179 Hanrahan et al. Jun 2002 B1
6400526 Crue, Jr. et al. Jun 2002 B2
6404600 Hawwa et al. Jun 2002 B1
6404601 Rottmayer et al. Jun 2002 B1
6404706 Stovall et al. Jun 2002 B1
6410170 Chen et al. Jun 2002 B1
6411522 Frank, Jr. et al. Jun 2002 B1
6417998 Crue, Jr. et al. Jul 2002 B1
6417999 Knapp et al. Jul 2002 B1
6418000 Gibbons et al. Jul 2002 B1
6418048 Sin et al. Jul 2002 B1
6421211 Hawwa et al. Jul 2002 B1
6421212 Gibbons et al. Jul 2002 B1
6424505 Lam et al. Jul 2002 B1
6424507 Lederman et al. Jul 2002 B1
6430009 Komaki et al. Aug 2002 B1
6430806 Chen et al. Aug 2002 B1
6433965 Gopinathan et al. Aug 2002 B1
6433968 Shi et al. Aug 2002 B1
6433970 Knapp et al. Aug 2002 B1
6437945 Hawwa et al. Aug 2002 B1
6445536 Rudy et al. Sep 2002 B1
6445542 Levi et al. Sep 2002 B1
6445553 Barr et al. Sep 2002 B2
6445554 Dong et al. Sep 2002 B1
6447935 Zhang et al. Sep 2002 B1
6448765 Chen et al. Sep 2002 B1
6451514 Iitsuka Sep 2002 B1
6452742 Crue et al. Sep 2002 B1
6452765 Mahvan et al. Sep 2002 B1
6456465 Louis et al. Sep 2002 B1
6459552 Liu et al. Oct 2002 B1
6462920 Karimi Oct 2002 B1
6466401 Hong et al. Oct 2002 B1
6466402 Crue, Jr. et al. Oct 2002 B1
6466404 Crue, Jr. et al. Oct 2002 B1
6468436 Shi et al. Oct 2002 B1
6469877 Knapp et al. Oct 2002 B1
6477019 Matono et al. Nov 2002 B2
6479096 Shi et al. Nov 2002 B1
6483662 Thomas et al. Nov 2002 B1
6487040 Hsiao et al. Nov 2002 B1
6487056 Gibbons et al. Nov 2002 B1
6490125 Barr Dec 2002 B1
6496330 Crue, Jr. et al. Dec 2002 B1
6496334 Pang et al. Dec 2002 B1
6504675 Shukh et al. Jan 2003 B1
6504676 Hiner et al. Jan 2003 B1
6512657 Heist et al. Jan 2003 B2
6512659 Hawwa et al. Jan 2003 B1
6512661 Louis Jan 2003 B1
6512690 Qi et al. Jan 2003 B1
6515573 Dong et al. Feb 2003 B1
6515791 Hawwa et al. Feb 2003 B1
6532823 Knapp et al. Mar 2003 B1
6535363 Hosomi et al. Mar 2003 B1
6552874 Chen et al. Apr 2003 B1
6552928 Qi et al. Apr 2003 B1
6577470 Rumpler Jun 2003 B1
6583961 Levi et al. Jun 2003 B2
6583968 Scura et al. Jun 2003 B1
6597548 Yamanaka et al. Jul 2003 B1
6611398 Rumpler et al. Aug 2003 B1
6618223 Chen et al. Sep 2003 B1
6629357 Akoh Oct 2003 B1
6633464 Lai et al. Oct 2003 B2
6636394 Fukagawa et al. Oct 2003 B1
6639291 Sin et al. Oct 2003 B1
6650503 Chen et al. Nov 2003 B1
6650506 Risse Nov 2003 B1
6654195 Frank, Jr. et al. Nov 2003 B1
6657816 Barr et al. Dec 2003 B1
6661621 Iitsuka Dec 2003 B1
6661625 Sin et al. Dec 2003 B1
6674610 Thomas et al. Jan 2004 B1
6680863 Shi et al. Jan 2004 B1
6683763 Hiner et al. Jan 2004 B1
6687098 Huai Feb 2004 B1
6687178 Qi et al. Feb 2004 B1
6687977 Knapp et al. Feb 2004 B2
6691226 Frank, Jr. et al. Feb 2004 B1
6697294 Qi et al. Feb 2004 B1
6700738 Sin et al. Mar 2004 B1
6700759 Knapp et al. Mar 2004 B1
6704158 Hawwa et al. Mar 2004 B2
6707083 Hiner et al. Mar 2004 B1
6710973 Okada et al. Mar 2004 B2
6713801 Sin et al. Mar 2004 B1
6721138 Chen et al. Apr 2004 B1
6721149 Shi et al. Apr 2004 B1
6721203 Qi et al. Apr 2004 B1
6722018 Santini Apr 2004 B2
6724569 Chen et al. Apr 2004 B1
6724572 Stoev et al. Apr 2004 B1
6729015 Matono et al. May 2004 B2
6731460 Sasaki May 2004 B2
6735850 Gibbons et al. May 2004 B1
6737281 Dang et al. May 2004 B1
6738223 Sato et al. May 2004 B2
6744608 Sin et al. Jun 2004 B1
6747301 Hiner et al. Jun 2004 B1
6751055 Alfoqaha et al. Jun 2004 B1
6754049 Seagle et al. Jun 2004 B1
6756071 Shi et al. Jun 2004 B1
6757140 Hawwa Jun 2004 B1
6760196 Niu et al. Jul 2004 B1
6762910 Knapp et al. Jul 2004 B1
6762911 Sasaki et al. Jul 2004 B2
6765756 Hong et al. Jul 2004 B1
6775902 Huai et al. Aug 2004 B1
6778358 Jiang et al. Aug 2004 B1
6781927 Heanuc et al. Aug 2004 B1
6785955 Chen et al. Sep 2004 B1
6791793 Chen et al. Sep 2004 B1
6791807 Hikami et al. Sep 2004 B1
6798616 Seagle et al. Sep 2004 B1
6798625 Ueno et al. Sep 2004 B1
6801408 Chen et al. Oct 2004 B1
6801411 Lederman et al. Oct 2004 B1
6803615 Sin et al. Oct 2004 B1
6806035 Atireklapvarodom et al. Oct 2004 B1
6807030 Hawwa et al. Oct 2004 B1
6807332 Hawwa Oct 2004 B1
6809899 Chen et al. Oct 2004 B1
6813116 Nakamura et al. Nov 2004 B2
6816345 Knapp et al. Nov 2004 B1
6828897 Nepela Dec 2004 B1
6829160 Qi et al. Dec 2004 B1
6829819 Crue, Jr. et al. Dec 2004 B1
6833979 Knapp et al. Dec 2004 B1
6834010 Qi et al. Dec 2004 B1
6857181 Lo et al. Feb 2005 B2
6859343 Alfoqaha et al. Feb 2005 B1
6859997 Tong et al. Mar 2005 B1
6861937 Feng et al. Mar 2005 B1
6870712 Chen et al. Mar 2005 B2
6873494 Chen et al. Mar 2005 B2
6873547 Shi et al. Mar 2005 B1
6879464 Sun et al. Apr 2005 B2
6888184 Shi et al. May 2005 B1
6888704 Diao et al. May 2005 B1
6891697 Nakamura et al. May 2005 B2
6891702 Tang May 2005 B1
6894871 Alfoqaha et al. May 2005 B2
6894877 Crue, Jr. et al. May 2005 B1
6903900 Sato et al. Jun 2005 B2
6906894 Chen et al. Jun 2005 B2
6909578 Missell et al. Jun 2005 B1
6912106 Chen et al. Jun 2005 B1
6934113 Chen Aug 2005 B1
6934129 Zhang et al. Aug 2005 B1
6940688 Jiang et al. Sep 2005 B2
6942824 Li Sep 2005 B1
6943993 Chang et al. Sep 2005 B2
6944938 Crue, Jr. et al. Sep 2005 B1
6947255 Hsiao et al. Sep 2005 B2
6947258 Li Sep 2005 B1
6950266 McCaslin et al. Sep 2005 B1
6950277 Nguy et al. Sep 2005 B1
6952325 Sato et al. Oct 2005 B2
6954332 Hong et al. Oct 2005 B1
6958885 Chen et al. Oct 2005 B1
6961221 Niu et al. Nov 2005 B1
6969989 Mei Nov 2005 B1
6975486 Chen et al. Dec 2005 B2
6987643 Seagle Jan 2006 B1
6989962 Dong et al. Jan 2006 B1
6989972 Stoev et al. Jan 2006 B1
6995949 Nakamura et al. Feb 2006 B2
7006326 Okada et al. Feb 2006 B2
7006327 Krounbi et al. Feb 2006 B2
7007372 Chen et al. Mar 2006 B1
7012832 Sin et al. Mar 2006 B1
7023658 Knapp et al. Apr 2006 B1
7026063 Ueno et al. Apr 2006 B2
7027268 Zhu et al. Apr 2006 B1
7027274 Sin et al. Apr 2006 B1
7035046 Young et al. Apr 2006 B1
7041985 Wang et al. May 2006 B1
7046490 Ueno et al. May 2006 B1
7054113 Seagle et al. May 2006 B1
7057857 Niu et al. Jun 2006 B1
7059868 Yan Jun 2006 B1
7070698 Le Jul 2006 B2
7092195 Liu et al. Aug 2006 B1
7100266 Plumer et al. Sep 2006 B2
7110289 Sin et al. Sep 2006 B1
7111382 Knapp et al. Sep 2006 B1
7113366 Wang et al. Sep 2006 B1
7114241 Kubota et al. Oct 2006 B2
7116517 He et al. Oct 2006 B1
7124654 Davies et al. Oct 2006 B1
7126788 Liu et al. Oct 2006 B1
7126790 Liu et al. Oct 2006 B1
7131346 Buttar et al. Nov 2006 B1
7133252 Takano et al. Nov 2006 B2
7133253 Seagle et al. Nov 2006 B1
7134185 Knapp et al. Nov 2006 B1
7139153 Hsiao et al. Nov 2006 B2
7154715 Yamanaka et al. Dec 2006 B2
7159302 Feldbaum et al. Jan 2007 B2
7170725 Zhou et al. Jan 2007 B1
7177117 Jiang et al. Feb 2007 B1
7185415 Khera et al. Mar 2007 B2
7193815 Stoev et al. Mar 2007 B1
7196880 Anderson et al. Mar 2007 B1
7199974 Alfoqaha Apr 2007 B1
7199975 Pan Apr 2007 B1
7206166 Notsuke et al. Apr 2007 B2
7211339 Seagle et al. May 2007 B1
7212379 Hsu et al. May 2007 B2
7212384 Stoev et al. May 2007 B1
7238292 He et al. Jul 2007 B1
7239478 Sin et al. Jul 2007 B1
7245454 Aoki et al. Jul 2007 B2
7248431 Liu et al. Jul 2007 B1
7248433 Stoev et al. Jul 2007 B1
7248449 Seagle Jul 2007 B1
7251878 Le et al. Aug 2007 B2
7253992 Chen et al. Aug 2007 B2
7280325 Pan Oct 2007 B1
7283327 Liu et al. Oct 2007 B1
7284316 Huai et al. Oct 2007 B1
7286329 Chen et al. Oct 2007 B1
7289303 Sin et al. Oct 2007 B1
7292409 Stoev et al. Nov 2007 B1
7296338 Le et al. Nov 2007 B2
7296339 Yang et al. Nov 2007 B1
7307814 Seagle et al. Dec 2007 B1
7307818 Park et al. Dec 2007 B1
7310204 Stoev et al. Dec 2007 B1
7318947 Park et al. Jan 2008 B1
7324304 Benakli et al. Jan 2008 B1
7333295 Medina et al. Feb 2008 B1
7337530 Stoev et al. Mar 2008 B1
7342752 Zhang et al. Mar 2008 B1
7349170 Rudman et al. Mar 2008 B1
7349179 He et al. Mar 2008 B1
7354664 Jiang et al. Apr 2008 B1
7363697 Dunn et al. Apr 2008 B1
7369359 Fujita et al. May 2008 B2
7371152 Newman May 2008 B1
7372665 Stoev et al. May 2008 B1
7375926 Stoev et al. May 2008 B1
7379269 Krounbi et al. May 2008 B1
7386933 Krounbi et al. Jun 2008 B1
7389577 Shang et al. Jun 2008 B1
7392577 Yazawa et al. Jul 2008 B2
7417832 Erickson et al. Aug 2008 B1
7419891 Chen et al. Sep 2008 B1
7428124 Song et al. Sep 2008 B1
7430095 Benakli et al. Sep 2008 B2
7430098 Song et al. Sep 2008 B1
7436620 Kang et al. Oct 2008 B1
7436638 Pan Oct 2008 B1
7440220 Kang et al. Oct 2008 B1
7441325 Gao et al. Oct 2008 B2
7443632 Stoev et al. Oct 2008 B1
7444740 Chung et al. Nov 2008 B1
7464457 Le et al. Dec 2008 B2
7469467 Gao et al. Dec 2008 B2
7493688 Wang et al. Feb 2009 B1
7508626 Ichihara et al. Mar 2009 B2
7508627 Zhang et al. Mar 2009 B1
7522377 Jiang et al. Apr 2009 B1
7522379 Krounbi et al. Apr 2009 B1
7522382 Pan Apr 2009 B1
7535675 Kimura et al. May 2009 B2
7542246 Song et al. Jun 2009 B1
7551406 Thomas et al. Jun 2009 B1
7552523 He et al. Jun 2009 B1
7554767 Hu et al. Jun 2009 B1
7558019 Le et al. Jul 2009 B2
7580222 Sasaki et al. Aug 2009 B2
7583466 Kermiche et al. Sep 2009 B2
7595967 Moon et al. Sep 2009 B1
7639451 Yatsu et al. Dec 2009 B2
7639452 Mochizuki et al. Dec 2009 B2
7639457 Chen et al. Dec 2009 B1
7643246 Yazawa et al. Jan 2010 B2
7660080 Liu et al. Feb 2010 B1
7663839 Sasaki et al. Feb 2010 B2
7672079 Li et al. Mar 2010 B2
7672080 Tang et al. Mar 2010 B1
7672086 Jiang Mar 2010 B1
7684160 Erickson et al. Mar 2010 B1
7688546 Bai et al. Mar 2010 B1
7691434 Zhang et al. Apr 2010 B1
7695761 Shen et al. Apr 2010 B1
7719795 Hu et al. May 2010 B2
7726009 Liu et al. Jun 2010 B1
7729086 Song et al. Jun 2010 B1
7729087 Stoev et al. Jun 2010 B1
7736823 Wang et al. Jun 2010 B1
7748104 Bonhote et al. Jul 2010 B2
7785666 Sun et al. Aug 2010 B1
7796356 Fowler et al. Sep 2010 B1
7796360 Im et al. Sep 2010 B2
7796361 Sasaki et al. Sep 2010 B2
7800858 Bajikar et al. Sep 2010 B1
7819979 Chen et al. Oct 2010 B1
7829264 Wang et al. Nov 2010 B1
7841068 Chen et al. Nov 2010 B2
7846643 Sun et al. Dec 2010 B1
7855854 Hu et al. Dec 2010 B2
7869160 Pan et al. Jan 2011 B1
7872824 Macchioni et al. Jan 2011 B1
7872833 Hu et al. Jan 2011 B2
7910267 Zeng et al. Mar 2011 B1
7911735 Sin et al. Mar 2011 B1
7911737 Jiang et al. Mar 2011 B1
7916425 Sasaki et al. Mar 2011 B2
7916426 Hu et al. Mar 2011 B2
7918013 Dunn et al. Apr 2011 B1
7924528 Sasaki et al. Apr 2011 B2
7968219 Jiang et al. Jun 2011 B1
7982989 Shi et al. Jul 2011 B1
8008912 Shang Aug 2011 B1
8012804 Wang et al. Sep 2011 B1
8015692 Zhang et al. Sep 2011 B1
8018677 Chung et al. Sep 2011 B1
8018678 Zhang et al. Sep 2011 B1
8024748 Moravec et al. Sep 2011 B1
8027125 Lee et al. Sep 2011 B2
8059367 Lee et al. Nov 2011 B2
8072705 Wang et al. Dec 2011 B1
8074345 Anguelouch et al. Dec 2011 B1
8077418 Hu et al. Dec 2011 B1
8077434 Shen et al. Dec 2011 B1
8077435 Liu et al. Dec 2011 B1
8077557 Hu et al. Dec 2011 B1
8079135 Shen et al. Dec 2011 B1
8081403 Chen et al. Dec 2011 B1
8091210 Sasaki et al. Jan 2012 B1
8097846 Anguelouch et al. Jan 2012 B1
8104166 Zhang et al. Jan 2012 B1
8116033 Kameda et al. Feb 2012 B2
8116043 Leng et al. Feb 2012 B2
8116171 Lee Feb 2012 B1
8125732 Bai et al. Feb 2012 B2
8125856 Li et al. Feb 2012 B1
8134794 Wang Mar 2012 B1
8136224 Sun et al. Mar 2012 B1
8136225 Zhang et al. Mar 2012 B1
8136805 Lee Mar 2012 B1
8141235 Zhang Mar 2012 B1
8146236 Luo et al. Apr 2012 B1
8149536 Yang et al. Apr 2012 B1
8151441 Rudy et al. Apr 2012 B1
8163185 Sun et al. Apr 2012 B1
8164760 Willis Apr 2012 B2
8164855 Gibbons et al. Apr 2012 B1
8164864 Kaiser et al. Apr 2012 B2
8165709 Rudy Apr 2012 B1
8166631 Tran et al. May 2012 B1
8166632 Zhang et al. May 2012 B1
8169473 Yu et al. May 2012 B1
8171618 Wang et al. May 2012 B1
8179636 Bai et al. May 2012 B1
8184399 Wu et al. May 2012 B2
8191237 Luo et al. Jun 2012 B1
8194365 Leng et al. Jun 2012 B1
8194366 Li et al. Jun 2012 B1
8196285 Zhang et al. Jun 2012 B1
8200054 Li et al. Jun 2012 B1
8203800 Li et al. Jun 2012 B2
8208350 Hu et al. Jun 2012 B1
8220140 Wang et al. Jul 2012 B1
8222599 Chien Jul 2012 B1
8225488 Zhang et al. Jul 2012 B1
8227023 Liu et al. Jul 2012 B1
8228633 Tran et al. Jul 2012 B1
8231796 Li et al. Jul 2012 B1
8233233 Shen et al. Jul 2012 B1
8233234 Hsiao et al. Jul 2012 B2
8233235 Chen et al. Jul 2012 B2
8233248 Li et al. Jul 2012 B1
8248728 Yamaguchi et al. Aug 2012 B2
8248896 Yuan et al. Aug 2012 B1
8254060 Shi et al. Aug 2012 B1
8257597 Guan et al. Sep 2012 B1
8259410 Bai et al. Sep 2012 B1
8259539 Hu et al. Sep 2012 B1
8262918 Li et al. Sep 2012 B1
8262919 Luo et al. Sep 2012 B1
8264792 Bai et al. Sep 2012 B2
8264797 Emley Sep 2012 B2
8264798 Guan et al. Sep 2012 B1
8270109 Ohtsu Sep 2012 B2
8270126 Roy et al. Sep 2012 B1
8276258 Tran et al. Oct 2012 B1
8277669 Chen et al. Oct 2012 B1
8279719 Hu et al. Oct 2012 B1
8284517 Sun et al. Oct 2012 B1
8288204 Wang et al. Oct 2012 B1
8289649 Sasaki et al. Oct 2012 B2
8289821 Huber Oct 2012 B1
8291743 Shi et al. Oct 2012 B1
8305711 Li et al. Nov 2012 B2
8307539 Rudy et al. Nov 2012 B1
8307540 Tran et al. Nov 2012 B1
8308921 Hiner et al. Nov 2012 B1
8310785 Zhang et al. Nov 2012 B1
8310901 Batra et al. Nov 2012 B1
8315019 Mao et al. Nov 2012 B1
8316527 Hong et al. Nov 2012 B2
8320076 Shen et al. Nov 2012 B1
8320077 Tang et al. Nov 2012 B1
8320219 Wolf et al. Nov 2012 B1
8320220 Yuan et al. Nov 2012 B1
8320722 Yuan et al. Nov 2012 B1
8322022 Yi et al. Dec 2012 B1
8322023 Zeng et al. Dec 2012 B1
8325569 Shi et al. Dec 2012 B1
8333008 Sin et al. Dec 2012 B1
8334093 Zhang et al. Dec 2012 B2
8336194 Yuan et al. Dec 2012 B2
8339738 Tran et al. Dec 2012 B1
8341826 Jiang et al. Jan 2013 B1
8343319 Li et al. Jan 2013 B1
8343364 Gao et al. Jan 2013 B1
8347488 Hong et al. Jan 2013 B2
8349195 Si et al. Jan 2013 B1
8351307 Wolf et al. Jan 2013 B1
8357244 Zhao et al. Jan 2013 B1
8373945 Luo et al. Feb 2013 B1
8375564 Luo et al. Feb 2013 B1
8375565 Hu et al. Feb 2013 B2
8381391 Park et al. Feb 2013 B2
8385157 Champion et al. Feb 2013 B1
8385158 Hu et al. Feb 2013 B1
8394280 Wan et al. Mar 2013 B1
8400731 Li et al. Mar 2013 B1
8404128 Zhang et al. Mar 2013 B1
8404129 Luo et al. Mar 2013 B1
8405930 Li et al. Mar 2013 B1
8409453 Jiang et al. Apr 2013 B1
8413317 Wan et al. Apr 2013 B1
8416540 Li et al. Apr 2013 B1
8419953 Su et al. Apr 2013 B1
8419954 Chen et al. Apr 2013 B1
8422176 Leng et al. Apr 2013 B1
8422342 Lee Apr 2013 B1
8422841 Shi et al. Apr 2013 B1
8424192 Yang et al. Apr 2013 B1
8441756 Sun et al. May 2013 B1
8443510 Shi et al. May 2013 B1
8444866 Guan et al. May 2013 B1
8449948 Medina et al. May 2013 B2
8451556 Wang et al. May 2013 B1
8451563 Zhang et al. May 2013 B1
8454846 Zhou et al. Jun 2013 B1
8455119 Jiang et al. Jun 2013 B1
8456961 Wang et al. Jun 2013 B1
8456963 Hu et al. Jun 2013 B1
8456964 Yuan et al. Jun 2013 B1
8456966 Shi et al. Jun 2013 B1
8456967 Mallary Jun 2013 B1
8458892 Si et al. Jun 2013 B2
8462592 Wolf et al. Jun 2013 B1
8468682 Zhang Jun 2013 B1
8472288 Wolf et al. Jun 2013 B1
8480911 Osugi et al. Jul 2013 B1
8486285 Zhou et al. Jul 2013 B2
8486286 Gao et al. Jul 2013 B1
8488272 Tran et al. Jul 2013 B1
8491801 Tanner et al. Jul 2013 B1
8491802 Gao et al. Jul 2013 B1
8493693 Zheng et al. Jul 2013 B1
8493695 Kaiser et al. Jul 2013 B1
8495813 Hu et al. Jul 2013 B1
8498084 Leng et al. Jul 2013 B1
8506828 Osugi et al. Aug 2013 B1
8514517 Batra et al. Aug 2013 B1
8518279 Wang et al. Aug 2013 B1
8518832 Yang et al. Aug 2013 B1
8520336 Liu et al. Aug 2013 B1
8520337 Liu et al. Aug 2013 B1
8524068 Medina et al. Sep 2013 B2
8526275 Yuan et al. Sep 2013 B1
8531801 Xiao et al. Sep 2013 B1
8532450 Wang et al. Sep 2013 B1
8533937 Wang et al. Sep 2013 B1
8537494 Pan et al. Sep 2013 B1
8537495 Luo et al. Sep 2013 B1
8537502 Park et al. Sep 2013 B1
8545999 Leng et al. Oct 2013 B1
8547659 Bai et al. Oct 2013 B1
8547667 Roy et al. Oct 2013 B1
8547730 Shen et al. Oct 2013 B1
8555486 Medina et al. Oct 2013 B1
8559141 Pakala et al. Oct 2013 B1
8563146 Zhang et al. Oct 2013 B1
8565049 Tanner et al. Oct 2013 B1
8576517 Tran et al. Nov 2013 B1
8578594 Jiang et al. Nov 2013 B2
8582238 Liu et al. Nov 2013 B1
8582241 Yu et al. Nov 2013 B1
8582253 Zheng et al. Nov 2013 B1
8588039 Shi et al. Nov 2013 B1
8593914 Wang et al. Nov 2013 B2
8597528 Roy et al. Dec 2013 B1
8599520 Liu et al. Dec 2013 B1
8599657 Lee Dec 2013 B1
8603593 Roy et al. Dec 2013 B1
8607438 Gao et al. Dec 2013 B1
8607439 Wang et al. Dec 2013 B1
8611035 Bajikar et al. Dec 2013 B1
8611054 Shang et al. Dec 2013 B1
8611055 Pakala et al. Dec 2013 B1
8614864 Hong et al. Dec 2013 B1
8619512 Yuan et al. Dec 2013 B1
8625233 Ji et al. Jan 2014 B1
8625941 Shi et al. Jan 2014 B1
8628672 Si et al. Jan 2014 B1
8630068 Mauri et al. Jan 2014 B1
8634280 Wang et al. Jan 2014 B1
8638529 Leng et al. Jan 2014 B1
8643980 Fowler et al. Feb 2014 B1
8649123 Zhang et al. Feb 2014 B1
8665561 Knutson et al. Mar 2014 B1
8670211 Sun et al. Mar 2014 B1
8670213 Zeng et al. Mar 2014 B1
8670214 Knutson et al. Mar 2014 B1
8670294 Shi et al. Mar 2014 B1
8670295 Hu et al. Mar 2014 B1
8675318 Ho et al. Mar 2014 B1
8675455 Krichevsky et al. Mar 2014 B1
8681594 Shi et al. Mar 2014 B1
8689430 Chen et al. Apr 2014 B1
8693141 Elliott et al. Apr 2014 B1
8703397 Zeng et al. Apr 2014 B1
8705205 Li et al. Apr 2014 B1
20030076630 Sato et al. Apr 2003 A1
20040061988 Matono et al. Apr 2004 A1
20040184191 Ichihara et al. Sep 2004 A1
20050117251 Matono et al. Jun 2005 A1
20060044677 Li et al. Mar 2006 A1
20060158779 Ota et al. Jul 2006 A1
20060174474 Le Aug 2006 A1
20060225268 Le et al. Oct 2006 A1
20060288565 Le et al. Dec 2006 A1
20070211380 Akimoto et al. Sep 2007 A1
20070236834 Toma et al. Oct 2007 A1
20070247746 Kim et al. Oct 2007 A1
20070258167 Allen et al. Nov 2007 A1
20070263324 Allen et al. Nov 2007 A1
20070283557 Chen et al. Dec 2007 A1
20080002309 Hsu et al. Jan 2008 A1
20080151437 Chen et al. Jun 2008 A1
20090279206 Yang et al. Nov 2009 A1
20100146773 Li et al. Jun 2010 A1
20100277832 Bai et al. Nov 2010 A1
20100290157 Zhang et al. Nov 2010 A1
20110051293 Bai et al. Mar 2011 A1
20110086240 Xiang et al. Apr 2011 A1
20110222188 Etoh et al. Sep 2011 A1
20120111826 Chen et al. May 2012 A1
20120216378 Emley et al. Aug 2012 A1
20120237878 Zeng et al. Sep 2012 A1
20120268845 Sahoo et al. Oct 2012 A1
20120298621 Gao Nov 2012 A1
20130216702 Kaiser et al. Aug 2013 A1
20130216863 Li et al. Aug 2013 A1
20130257421 Shang et al. Oct 2013 A1
Non-Patent Literature Citations (1)
Entry
U.S. Appl. No. 13/631,808, filed Sep. 28, 2012, to Liu et al., 16 pages.
Provisional Applications (1)
Number Date Country
61876340 Sep 2013 US