Electrical connection arrangement for a multiple sensor array usable in two-dimensional magnetic recording

Information

  • Patent Grant
  • 9431032
  • Patent Number
    9,431,032
  • Date Filed
    Friday, October 4, 2013
    11 years ago
  • Date Issued
    Tuesday, August 30, 2016
    8 years ago
Abstract
A method and system provide a magnetic transducer including first and second read sensors, a shield and a conductive via. The shield is between the first and second read sensors. The magnetic transducer also includes first and second read shields. The shield has a top surface and a bottom surface opposite to the top surface. The bottom surface faces the first read sensor. The conductive via is isolated from the first read shield and the second read shield. The conductive via provides electrical contact to the shield and is electrically connected to the bottom surface of the shield.
Description
BACKGROUND


FIG. 1 depicts an air-bearing surface (ABS) view of a conventional read transducer 10. The conventional read transducer 10 includes shields 12 and 20, sensor 14 and magnetic bias structures 16. The read sensor 14 is typically a giant magnetoresistive (GMR) sensor or tunneling magnetoresistive (TMR) sensor. The read sensor 14 includes an antiferromagnetic (AFM) layer, a pinned layer, a nonmagnetic spacer layer, and a free layer. Also shown is a capping layer. In addition, seed layer(s) may be used. The free layer has a magnetization sensitive to an external magnetic field. Thus, the free layer functions as a sensor layer for the magnetoresistive sensor 14. The magnetic bias structures 16 may be hard bias structures or soft bias structures. These magnetic bias structures are used to magnetically bias the sensor layer of the sensor 14.


Although the conventional magnetic recording transducer 10 functions, there are drawbacks. In particular, the conventional magnetic recording transducer 10 may not function adequately at higher recording densities. Two-dimensional magnetic recording (TDMR) technology may enable significantly higher recording densities. In TDMR, multiple read sensors are used. These sensors are longitudinally distributed along the cross track direction but are aligned in the down track direction. The sensors are separated by a particular distance in the cross track direction. In addition, the sensors have the same length (and read track width) in the cross track direction. This length is typically not more than fifty percent of the track width. The central sensor reads the data from a track of interest, while the outer sensors sense the data in adjacent tracks in order to account for noise.


Although TDMR might be capable of higher recording densities, issues may be faced at skew. For example, in some recording applications, such as shingled recording, the skew angle changes. As a result, the transducer may not perform as desired for all skew angles. In addition, providing electrical connection to the sensors may be challenging. Accordingly, what is needed is a system and method for improving the performance of a magnetic recording read transducer, particular for TDMR.





BRIEF DESCRIPTION OF SEVERAL VIEWS OF THE DRAWINGS


FIG. 1 depicts a conventional read transducer.



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



FIGS. 3A and 3B depict ABS and side views of an exemplary embodiment of a portion of a magnetic recording read transducer.



FIGS. 4A and 4B depict ABS and side views of another exemplary embodiment of a portion of a magnetic recording read transducer.



FIG. 5 is a flow chart depicting an exemplary embodiment of a method for fabricating a magnetic recording read transducer.



FIG. 6 is a flow chart depicting an exemplary embodiment of a method for fabricating shield(s) and connections for a magnetic recording read transducer.



FIGS. 7A-7C depict perspective views of another exemplary embodiment of a portion of a magnetic recording read transducer.



FIGS. 8A-8C depict plan views of another exemplary embodiment of a portion of a magnetic recording read transducer.



FIGS. 9A-9C depict plan views of another exemplary embodiment of a portion of a magnetic recording read transducer.



FIG. 10 is a flow chart depicting another exemplary embodiment of a method for fabricating shield(s) and connections for a magnetic recording read transducer.



FIGS. 11A-11C depict perspective views of another exemplary embodiment of a portion of a magnetic recording read transducer.



FIGS. 12A-12C depict plan views of another exemplary embodiment of a portion of a magnetic recording read transducer.



FIGS. 13A-13C depict plan views of another exemplary embodiment of a portion of a magnetic recording read transducer.





DETAILED DESCRIPTION OF THE EXEMPLARY EMBODIMENTS


FIG. 2 depicts a side view of an exemplary embodiment of a disk drive 100. For clarity, FIG. 2 is not to scale. For simplicity not all portions of the disk drive 100 are shown. In addition, although the disk drive 100 is 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 are shown. However, multiples of one or more of the components and/or their sub-components might be used.


The disk drive 100 includes media 101, a slider 102, a head 103 including a write transducer 104 and a read transducer 110. The write transducer includes at least a write pole 106 and coil(s) 108 for energizing the pole 106. Additional and/or different components may be included in the disk drive 100. Although not shown, the slider 102, and thus the transducers 104 and 110 are generally attached to a suspension (not shown). The transducers 104 and 110 are fabricated on the slider 102 and include an ABS proximate to the media 101 during use. Although both a write transducer 104 and a read transducer 110 are shown, in other embodiments, only a read transducer 110 may be present.


The read transducer 110 includes multiple read sensors 112, 114 and 116. The read sensors 112, 114 and 116 include sensor layers that may be free layers in a magnetoresistive junction such as a giant magnetoresistive (GMR) sensor, a tunneling magnetoresistive (TMR) sensor. Thus, each sensor 112, 114 and 116 may include a pinning layer, a pinned layer, a nonmagnetic spacer layer and a free layer. Other layer(s) may also be present. For example, the sensors 112, 114 and 116 may also include seed layer(s) (not shown) and capping layer(s) (not shown). Although described as a GMR or TMR sensor, in other embodiments, other structures and other sensing mechanisms may be used for the sensor.


The read sensors are separated by shields 130 and 140. The read sensors 112, 114 and 116 and shields 130 and 140 are surrounded by read shields 120 and 150. Thus, as used herein, a shield may be considered to be an internal shield, which is interleaved with read sensors and between the outer, read shields. The outermost shields for the read transducer 110 are termed read shields. In the embodiment shown in FIG. 2, three read sensors 112, 114 and 116 and two internal shields 130 and 140 are shown. However, in another embodiment, another number of read sensors 112, 114 and 116 and internal shields 130 and 140 may be present. The shields/read shields 120, 130, 140 and 150 generally include soft magnetic material. In some embodiments, one or more of the shields 120, 130, 140 and 150 may include ferromagnetic layers that are antiferromagnetically coupled.


Current is driven perpendicular-to-plane for the sensors 112, 114 and 116. Thus, current is driven through the sensor 112 between the shields 120 and 130. Similarly, current is driven through the sensor 114 between the shields 130 and 140. Current is also driven through the sensor 116 between the shields 140 and 150. Thus, electrical connection is to be made to the shields 120, 130, 140 and 150. Such contacts are described below. The read transducer 110 may be used in higher density recording, such as TDMR.



FIGS. 3A and 3B depict ABS and side views, respectively, of an exemplary embodiment of the disk drive 100 depicted in FIG. 2. For clarity, FIGS. 3A-3B are not to scale. For simplicity not all portions of the disk drive 100 are shown. In addition, although the disk drive 100 is 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 are shown. However, multiples of one or more of the components and/or their sub-components might be used.


In the embodiment shown in FIGS. 3A-3B, the read transducer 110 on the slider 102 and tracks 109 of the media 101 are shown. The read transducer 110 includes multiple read sensors 112, 114 and 116. The read sensors 112, 114 and 116 include sensor layers 113, 115 and 117, respectively, that may be free layers in a magnetoresistive junction such as a GMR sensor or a TMR sensor. Thus, each sensor 112, 114 and 116 may include a pinning layer, a pinned layer, a nonmagnetic spacer layer and a free layer 113, 115, and 117, respectively. For simplicity, only the free layers 113, 115 and 117 are separately labeled in FIGS. 3A-3B. The sensors 112, 114 and 116 may also include seed layer(s) (not shown) and capping layer(s) (not shown). The pinning layer is generally an AFM layer that is magnetically coupled to the pinned layer. In other embodiments, however, the pinning layer may be omitted or may use a different pinning mechanism. The free layers 113, 115 and 117 are each shown as a single layer, but may include multiple layers including but not limited to a synthetic antiferromagnetic (SAF) structure. The pinned layer may also be a simple layer or a multilayer. Although shown as extending the same distance from the ABS, the pinned layer may extend further than the corresponding free layer 113, 115, and/or 117, respectively. The nonmagnetic spacer layer may be a conductive layer, a tunneling barrier layer, or other analogous layer. Although depicted as a GMR or TMR sensor, in other embodiments, other structures and other sensing mechanisms may be used for the sensor.


The read sensors 112, 114 and 116 are separated by distances d1 and d2 in a down track direction. The down track direction is perpendicular to the cross track direction. The cross track direction and track width direction are the same. In the embodiment shown in FIGS. 3A-3B, the distance d1 and d2 between the sensors 112 and 114 and between the sensors 114 and 116, respectively, are the same. However, in other embodiments, the distances between the sensors 112, 114 and 116 may not be the same. It is generally desirable to reduce the distance between the sensors 112, 114 and 116 in order to reduce the skew effect. The distances d1 and d2 may each be at least ten nanometers and not more than four hundred nanometers. The read sensors 112, 114 and 116 have multiple widths, w1, w2 and w3, respectively, in the track width direction. In the embodiment shown, the sensors 112 and 116 have the same width. However, in other embodiments, other widths are possible. The widths of the sensors 112, 114 and 116 may also be based on the track pitch. The track pitch is the distance from the center of one track to the center of the next track. The width, w2, is at least fifty and not more than one hundred twenty percent of the track pitch. In some such embodiments, the width of the sensor 114 is at least eighty percent and not more than one hundred percent of the track pitch. In some embodiments, the widths w1 and w3 are at least equal to the track pitch and not more than twice the track pitch. In some such embodiments, the widths w1 and w3 are each at least one hundred twenty percent and not more than one hundred fifty percent of the track pitch. However, the widths w1 and w3 may be less than or equal to the track pitch. Further, the widths may depend not only on the track pitch, but also on the distance between the sensors 112, 114 and 116.


The read sensors 112, 114 and 116 may also be displaced along the cross track direction. Therefore, the centers of each of the read sensors 112, 114 and 116 are not aligned along a vertical line that runs the down track direction. The read sensors 112, 114 and 116 may also overlap in the track width/cross track direction. The amount of overlap may depend upon the distances d1 and d2 between the sensors 112, 114 and 116. In some embodiments, the overlap may be different. For example, the sensors 112, 114 and 116 may not overlap, but instead be spaced apart. In other embodiments, the sensors 112, 114 and 116 may be aligned such that they overlap substantially completely. In the embodiment shown, the sensor 114 in the center in the down track direction is also in the center of the remaining sensors 112 and 116 in the track width direction. However, other configurations are possible.


Also shown are bias structures 122, 123 and 124 that magnetically bias the read sensors 112, 114 and 116, respectively. The magnetic bias structure(s) 122, 123 and/or 124 may be soft bias structures fabricated with soft magnetic material(s). In other embodiments, the magnetic bias structure(s) 122, 123 and/or 124 may be hard magnetic bias structures. Other mechanisms for biasing the sensors 112, 114 and 116 might also be used.


The read sensors are separated by shields 130 and 140 as well as insulators 125, 126 and 127. In the embodiment shown, therefore, the sensor 112 may be electrically connected to the sensor 114 through the shield 130. Similarly, the sensor 114 may be electrically connected to the sensor 116 through the shield 140. In some embodiments, one or more of the shields 120, 130, 140 and 150 may include ferromagnetic layers that are antiferromagnetically coupled. Further, the shields 120, 130, 140 and 150 have top surfaces and bottom surfaces opposite to the top surfaces. These surfaces are perpendicular to the down track direction. The bottom surface of each shield 120, 130, 140 and 150 is closer to the substrate (not shown) than the top surface. Thus, the bottom surface of the shield 130 faces the read shield 120 and is connected to the read sensor 112, while the top surface of the shield 130 faces the shield 140. Similarly, the bottom surface of the shield 140 faces the shield 130 and is connected to the read sensor 114, while the top surface of the shield 140 faces the read shield 150.


Electrical connection is to be made to the shields 120, 130, 140 and 150 using the conductive vias 160, 162 and 164. In some embodiments, the vias 160, 162 and 164 may be formed of high conductivity materials such as Cu and/or Ag. Although not shown, a conductive via may be used to provide electrical connection to the read shield 120. The conductive vias 160, 162 and 164 provide electrical connection to the bottoms of the shields 130, 140 and 150, respectively. Thus, the conductive via(s) 160, 162 and 164 are between the shields 130, 140 and 150, respectively, and the substrate/remaining portion of the slider 102. The conductive vias 160, 162 and 164 are shown as distributed in the stripe height direction. The conductive vias 160, 162 and 164 may be distributed both in the cross track direction and the stripe height direction. In still other embodiments, the conductive vias may be distributed in the cross track direction instead of the stripe height direction. In the embodiment shown, the conductive via 160 passes through an aperture or notch in the read shield 120. In other embodiments, the conductive via may be isolated from the read shield 120 in a different manner. For example, the read shield 120 may terminate closer to the ABS than the location of the conductive via 160. Stated differently, the back edge (edge opposite to the ABS) of the read shield 120 may be closer to the ABS than the conductive via 160. Thus, the conductive via 160 is not only physically and electrically connected to the shield 130 but also electrically isolated from the read shield 120. Similarly, the conductive via 162 passes through an aperture or notch in the read shield 120 and an aperture or notch in the shield 130. In other embodiments, the conductive via 163 may be isolated from the read shield 120 and/or shield 130 in a different manner. For example, the read shield 120 and/or shield 130 may have a back edge that is closer to the ABS than the conductive via 162. Thus, the conductive via 162 is not only physically and electrically connected to the shield 140 but also electrically isolated from the read shield 120 and the shield 130. Note, however, that the conductive vias 160 and 162 are electrically connected to the read shield 120 and shield 130 through the sensors 112 and 114. Similarly, the conductive via 164 is physically and electrically connected to the read shield 150. However, the conductive via is electrically isolated from the remaining shields 120, 130 and 140. In some embodiments, this may be accomplished by passing the conductive via 164 through aperture(s) and/or notch(es) in the shields 120, 130 and 140. However, in other embodiments, the back edges of the shields 120, 130 and/or 140 terminated closer to the ABS than the conductive via 164. In other embodiments, with fewer shields and/or fewer read sensors, another number of conductive vias may be used. For example, if the sensor 112 and shield 130 were omitted, then the via 160 may be omitted. In some embodiments, a preamplifier may be coupled between the read shield 150 and the shield 140. Another preamplifier may be coupled between the shields 130 and 140. A third preamplifier may be coupled between the shield 130 and the read shield 120. Thus, signals may be read from the sensors 112, 114 and 116.


In some embodiments, the conductive vias 160, 162 and/or 164 are stacked vias that are formed layer by layer with the remainder of the transducer 110. For example, the lowest layer in the vias 160162 and 164 may be formed substantially at the same time as the read shield 120 is formed. Via holes may be formed in the read shield 120, then an insulator and a part of each of the conductive vias 160, 162 and/or 164 formed in the via holes. After deposition of the insulator 125, via holes are formed and filled with a conductive material. Thus, the next level of the conductive vias 160, 164 and 166 is completed. Similar processes may be carried out for each subsequent layer including but not limited to the shields 130 and 140. For such an embodiment, the layers formed are indicated by dotted lines in the conductive vias 160, 162 and 164. In some embodiments, pads (not shown) may also be formed at these locations. However, these pads do not electrically connect the conductive vias to the shield/shield layers. In other embodiments, the conductive via(s) 160, 162 and 164 may be formed as a single monolithic structure. For example, a via hole may be formed in the read shield and insulating layer 125 at or near the same time as the shield 130 is formed. The via hole is then filled to form the conductive via 160. Later, a via hole is formed in the insulators 125 and 126, shield 130 and read shield 120. The conductive via 162 is then formed in the via hole. Thus, each conductive via 160, 162 and 164 is a monolithic structure. Also shown in FIG. 3B are conductive pads used to connect the conductive vias 160, 162 and 164 with the corresponding shield 130, 140 and 150. However, in other embodiments, the pads may be omitted. Finally, connecting the conductive via 160, 162 and 164 with the corresponding shield 130, 140 and 150, respectively, may be completed in a different manner. For example, apertures corresponding to the vias 160, 162 and 164 may be formed in the shields 130, 140 and 150. These apertures may then be refilled with a conductive material to make electrical contact with the underlying conductive via 160, 162 and/or 164. The material used for the refill may be magnetic or, in alternate embodiments, nonmagnetic.


The read transducer 110 may be used in higher density recording, such as TDMR. Through the placement of the sensors 112, 114 and 116, the transducer 110 may address skew issues that might otherwise adversely affect performance of the transducer 110. In applications such as TDMR, the sensors 112 and 116 may be better able gather data for cancellation of noise from the tracks 109 adjacent to the track 109 being read. Thus, reading of very high density tracks may be accomplished. Further, the transducer 110 may be scalable. In addition, the conductive vias 160 and 162 may provide electrical contact to the shields 140 and 130 with a relatively modest contact resistance.



FIGS. 4A and 4B depict ABS and side views, respectively, of an exemplary embodiment of the disk drive 100′ analogous to the disk drive 100 depicted in FIGS. 2-3B. Similar components have analogous labels. For clarity, FIGS. 4A-4B are not to scale. For simplicity not all portions of the disk drive 100′ are shown. In addition, although the disk drive 100′ is 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 are shown. However, multiples of one or more of the components and/or their sub-components might be used.


The disk drive 100′ is analogous to the disk drive 100. Thus, FIGS. 4A-4B depict a read transducer 110′ on the slider 102 and tracks 109 of the media 101 are shown that are analogous to the read transducer 110 and tracks 109. The read transducer 110′ includes multiple read sensors 112, 114 and 116, read shields 120 and 150 and bias structures 122, 123 and 124 that are analogous to the sensors 112, 114 and 116, read shields 120 and 150 and bias structures 122, 123 and 124, respectively. The sensor layers 113, 115 and 117 are analogous to the sensors layers 113, 115 and 117, respectively, depicted in FIBS. 3A-3B.


Referring back to FIGS. 4A-4B, the shields 130′ and 140′ are analogous to the shields 130 and 140. However, the shields 130′ and 140′ are multilayers. In particular, the shield 130′ includes shield layers 132 and 136 separated by insulating layer 134. The shield layers 132 and 136 are magnetic and conductive. In some embodiments, one or more of the shield layers 132 and 136 includes antiferromagnetically coupled sublayers. Similarly, the shield 140′ includes shield layers 142 and 146 separated by insulting layer 144. The shield layers 142 and 146 are magnetic and conductive. In some embodiments, one or more of the shield layers 142 and 146 includes antiferromagnetically coupled sublayers. Further, the shield layers 132, 136, 142 and 146 have top surfaces and bottom surfaces opposite to the top surfaces. These surfaces are perpendicular to the down track direction. The bottom surface of each shield layer 132, 136, 142 and 150 is closer to the substrate (not shown) than the top surface. Thus, the bottom surface of the shield layer 132 faces the read shield 120 and is connected to the read sensor 112. The top surface of the shield layer 136 faces the shield 140 and is electrically connected to the read sensor 114. Similarly, the bottom surface of the shield layer 142 faces the shield 130 and is connected to the read sensor 114. The top surface of the shield layer 146 faces the read shield 150 and is electrically connected to the sensor 116.


Because of the configuration of the shields 130′ and 140′, the sensors 112, 114 and 116 may be electrically isolated. In particular, the sensor 112 is coupled with read shield 120 and the bottom shield layer 132 of the shield 130′. The read sensor 114 is electrically coupled with the top shield layer 136 of the shield 130′ and the bottom shield layer 142 of the shield 140′. Finally, the read sensor 116 is electrically connected with the top shield layer 146 of the shield 140′ and the bottom of the read shield 150. However, because of the presence of the insulating layers 134 and 144, the read sensors 112, 114 and 116 may not be electrically connected through the shields 130 and 140.


Current is driven through the sensor 112 between the shields 120 and 130′. Similarly, current is driven through the sensor 114 between the shields 130′ and 140′. Current is also driven through the sensor 116 between the shields 140′ and 150. Thus, electrical connection is to be made to the shields 120, 130′, 140′ and 150. The conductive vias 160′, 161, 162′, 163 and 164 shown are used to provide electrical contact to the shields 130′, 140′ and 150. In some embodiments, the conductive vias 160′, 161, 162′, 163 and 164 may be formed of high conductivity materials such as Cu and/or Ag. The conductive vias 160′, 161, 162′, 163 and 164 are shown as distributed in the stripe height direction. The conductive vias 160′, 161, 162′, 163 and 164 may be distributed in both the cross-track direction and the stripe height direction. In still other embodiments, the conductive vias 160′, 161, 162′, 163 and 164 may be distributed in the cross track direction instead of the stripe height direction. Although not shown, a conductive via may be used to provide electrical connection to the read shield 120.


The conductive vias 160′, 162′ and 164 provide electrical connection to the bottoms of the shield layer 132, the shield layer 142 and read shield 150, respectively. In the embodiment shown, the conductive via 160′ passes through an aperture or notch in the read shield 120. In other embodiments, the conductive via may be isolated from the read shield 120 in a different manner. For example, the back edge of the read shield 120 may be closer to the ABS than the conductive via 160′. Thus, the conductive via 160′ is not only physically and electrically connected to the shield layer 132 but also electrically isolated from the read shield 120. The conductive via 161 passes through an aperture or notch in the read shield 120 as well as an aperture or notch in the shield layer 132. The conductive via 161 thus contacts with the bottom of shield layer 136. Similarly, the conductive via 162′ passes through an aperture or notch in the read shield 120 and an aperture or notch in the layers 132, 134 and 136 of the shield 130′. In other embodiments, the conductive via 162′ may be isolated from the read shield 120 and/or shield 130′ in a different manner. For example, the read shield 120 and/or shield layers 132 and 136 may have a back edge that is closer to the ABS than the conductive via 162′. The conductive via 162′ electrically contacts the bottom of the shield layer 142 of the shield 140′. Thus, the conductive via 162′ is not only physically and electrically connected to the shield layer 142 but also electrically isolated from the read shield 120 and the shield 130′. Similarly, the conductive via 163 electrically contacts the bottom of the shield layer 146 of the shield 140′. Thus, the conductive via 163 is not only physically and electrically connected to the shield layer 146 of the shield 140′ but also electrically isolated from the read shield 120 and the shield 130′. The conductive via 164 is physically and electrically connected to the read shield 150. However, the conductive via is electrically isolated from the remaining shields 120, 130′ and 140′ in an analogous manner to that described above.


In some embodiments, the conductive vias 160′, 161, 162′, 163 and/or 164 are stacked vias that are formed layer by layer with the remainder of the transducer 110. In the embodiment shown, pads that are used to connect the vias to their corresponding shield/shield layers are also shown. In other embodiments, such pads may be omitted. For such an embodiment, the layers formed are indicated by dashed lines in the conductive vias 160′, 161, 162′, 163 and 164 that do not contact a shield/shield layer. In other embodiments, the conductive via(s) 160′, 161, 162′, 163 and/or 164 may be formed as a single monolithic structure. Also shown in FIG. 4B are conductive pads used to connect the conductive vias 160′, 161, 162′, 163 and 164 with the corresponding shield 130′, 140′ and 150. However, in other embodiments, the pads may be omitted. Although depicted as simply contacting the bottom of the shield, in other embodiments, the conductive vias 160′, 161, 162′ and 163 may be formed by providing an aperture in the corresponding shield layer(s) 132, 136, 142 and 146, respectively, then filling the aperture with conductive material(s). These material(s) may be magnetic or nonmagnetic.


The read transducer 110′ may be used in higher density recording, such as TDMR. Through the placement of the sensors 112, 114 and 116, the transducer 110′ may address skew issues that might otherwise adversely affect performance of the transducer 110′. In applications such as TDMR, the sensors 112 and 116 may be better able gather data for cancellation of noise from the tracks 109 adjacent to the track being read. Thus, reading of very high density tracks may be accomplished. Further, the transducer 110′ may be scalable. In addition, the conductive vias 160′, 161, 162′ and 163 may provide electrical contact to the shields 140′ and 130′ with a relatively modest contact resistance.



FIG. 5 is an exemplary embodiment of a method 200 for providing a read transducer including multiple read sensors. For simplicity, some steps may be omitted, interleaved, and/or combined. The method 200 is also described in the context of providing a single recording transducer 110/110′ in the disk drives 100 and 100′ depicted in FIGS. 2-4B. However, the method 200 may be used to fabricate multiple transducers at substantially the same time. The method 200 may also be used to fabricate other transducers including but not limited to any combination of those disclosed herein. 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 transducer.


The first read shield 120 is provided, via step 202. Step 202 typically includes depositing a large high permeability layer. The read sensor 112 is provided, via step 204. Step 204 includes depositing the layers for the sensor 112 and defining the sensor 112 in at least the track width direction using an ion mill. In some embodiments, the free layer 113 and the pinned layer of the sensor 112 is also defined in the stripe height direction. The magnetic bias structures for the sensor 112 may also be provided as part of step 204.


The shield 130/130′ is provided, via step 206. In some embodiments, step 206 includes depositing a soft magnetic material, such as NiFe. Step 206 may also include depositing and patterning the layers 132, 134 and 136 of the shield 130′. The read sensor 114 is provided, via step 208. Step 208 includes depositing the layers for the sensor 114 and defining the sensor 114 in at least the track width direction using an ion mill. In some embodiments, the free layer 115 and the pinned layer of the sensor 114 is also defined in the stripe height direction. The magnetic bias structures for the sensor 114 may also be provided.


If sensor 116 is to be used, then the shield 140/140′ and sensor 116 may be provided in a manner analogous to steps 204 and 206. If, however, two sensors 112 and 114 are to be used, then the read shield 150 is provided, via step 210. Step 210 may include forming a shield having ferromagnetic layers which are antiferromagnetically coupled. In other embodiments, other multilayers or a single layer may be formed.


Conductive vias 160, 162, 160′, 161, 162′, 163 and/or 164 are provided, via step 212. Step 212 includes forming conductive vias 160, 162, 160′, 161, 162′, 163 and/or 164 below the corresponding shield 130/130′, 140/140′ and 150 such that the conductive vias 160, 162, 160′, 161, 162′, 163 and/or 164 contact the bottom of the corresponding shield 130/130′, 140/140′ and 150 and/or shield layer 132, 136, 142 and 146. Thus, the benefits of the magnetic transducer(s) 110, and/or 110′ may be achieved.



FIG. 6 is an exemplary embodiment of a method 220 for providing shield(s) and stacked conductive vias in a read transducer including multiple read sensors. For simplicity, some steps may be omitted, interleaved, and/or combined. The method 220 is also described in the context of providing a single recording transducer 110/110′ in the disk drives 100 and 100′ depicted in FIGS. 2-4B. However, the method 220 may be used to fabricate multiple transducers at substantially the same time. The method 220 may also be used to fabricate other transducers including but not limited to any combination of those disclosed herein. The method 220 is also described in the context of particular layers. A particular layer may include multiple materials and/or multiple sub-layers. The method 220 also may start after formation of other portions of the magnetic recording transducer.


Insulating layer(s) 125 are deposited, via step 222. Step 222 is performed after any other underlying structures are formed. The via hole(s) for the conductive vias 160/160′, 161, 162/162′, 163 and 164 are formed, via step 224. These via holes may then be filled with a conductor, via step 226. Thus, the same layer for all of the conductive vias 160/160′, 161, 162/162′, 163 and 164 substantially during the same steps. In some embodiments, the layers may be planarized after formation of the layer for the conductive vias.


The corresponding shield/shield layer 130/132 is then formed, via step 228. Step 228 includes configuring the shield/shield layer 130/132 for the conductive vias remaining to be formed. For example, notches or apertures may be provided in the shield/shield layer 130/132. This may be accomplished by providing an etch mask having apertures over the desired regions and removing portions of the shield/shield layer 130/132. A portion of the notch or aperture may be partially filled with an insulator to ensure that the remaining conductive vias are insulated from the shield 130/shield layer 132. In other embodiments, the back edge of the shield/shield layer 130/132 may be configured to be between the ABS and the remaining conductive vias. Steps 222 through 228 may then be repeated for conductive vias making electrical contact to subsequent layers, via step 230.



FIGS. 7A-7C depict an exemplary embodiment of a portion of a magnetic transducer 250 during fabrication using the method 220. For clarity, only shield/shield layers and conductive vias are shown. FIGS. 7A-7C are not to scale. The transducer 250 is analogous to the read transducers 110 and 110′. FIG. 7A depicts the transducer 250 after steps 222-228 have been carried out. Thus, underlying pads 252 for the conductive vias are shown. The shield/shield layer 260 is also depicted. Conductive via 254 makes contact to the bottom of the shield/shield layer 260. The bottom layer of the remaining conductive vias 256 is also shown as having been formed. These structures 254 and 256 may be formed in steps 222-226. Apertures 262 are present (of which only one is labeled) in the shield/shield layer 260 for remaining conductive vias. Note that the conductive vias being fabricated are shown as distributed along the cross track direction. However, in other embodiments, the conductive vias may be distributed along the stripe height direction or along both the stripe height and cross track directions.



FIG. 7B depicts the transducer 250 after the next shield/shield layer 270 is formed using a second iteration of steps 222-228 through step 230. Thus, the conductive via 264 making contact to shield layer 270 is shown. The next layer 266 for the remaining conductive vias is also shown. Apertures 272 above this layer 266 have also been formed in the shield 270 in step 228. As can be seen in FIG. 7B, the conductive vias 254 and 264 only make contact to the corresponding shield/shield layer 260 and 270, respectively. The layers 256 and 266 for the remaining conductive vias are isolated from the shield/shield layers 260 and 270.



FIG. 7C depicts the transducer 250 after the conductive vias have been formed using multiple iterations of steps 222-228. Thus, shield/shield layers 280, 282, 284 and 286 have also been formed. Conductive via layers 274, 281, 283 and 285 have also been formed. The layers 274, 281, 283 and 285 make electrical contact only to corresponding shield/shield layers 280, 282, 284 and 286, respectively.



FIGS. 8A-8C depict plan views an exemplary embodiment of a portion of a magnetic transducer 250′ during fabrication using the method 220. For clarity, only shield/shield layers and conductive vias are shown. FIGS. 8A-8C are not to scale. The transducer 250′ is analogous to the read transducers 110 and 110′. FIG. 8A depicts the transducer 250′ after steps 222-228 have been carried out. Thus, underlying pads 252′ for the conductive vias are shown. Conductive via 254′ makes contact to the bottom of the shield/shield layer 260′. The bottom layer of the remaining conductive vias 256′ is also shown as having been formed and is depicted using dotted lines. The shield/shield layer 260′ is also depicted. Notches 262′ are present (of which only one is labeled) in the shield/shield layer 260′ for remaining conductive vias. Note that the conductive vias being fabricated are shown as distributed along the cross track direction. However, in other embodiments, the conductive vias may be distributed along the stripe height direction or along both the stripe height and cross track directions.



FIG. 8B depicts the transducer 250′ after the next shield/shield layer 270′ is formed using an additional iteration of the steps 222-228. Thus, the conductive via 264′ making contact to shield layer 270′ is shown. The next layer 266′ for the remaining conductive vias is also shown. Notches 272′ in the shield/shield layer 270′ above this layer 266′ have also been formed. The conductive vias 254′ and 264′ only make contact to the corresponding shield/shield layer 260′ and 270′, respectively. The layers 256′ and 266′ for the remaining conductive vias are isolated from the shield/shield layers 260′ and 270′.



FIG. 8C depicts the transducer 250′ after the conductive vias have been formed by multiple iterations of steps 222-228, via step 230. Thus, shield/shield layers 280′, 282′, 284′ and 286′ have also been formed. Conductive via layers 274′, 281′, 283′ and 285′ have also been formed. The layers 274′, 281′, 283′ and 285′ make electrical contact only to corresponding shield/shield layers 280′, 282′, 284′ and 286′, respectively. The top shield layer 286′ may have no notches because contact is made to the last conductive via. Notches in the underlying shield/shield layers 260′, 270′, 280′, 282′ and 284′ are shown by dashed lines.



FIGS. 9A-9C depict plan views an exemplary embodiment of a portion of a magnetic transducer 250″ during fabrication using the method 220. For clarity, only shield/shield layers and conductive vias are shown. FIGS. 9A-9C are not to scale. The transducer 250″ is analogous to the read transducers 110 and 110′. FIG. 9A depicts the transducer 250″ after steps 222-228 have been carried out. Thus, underlying pads 252″ for the conductive vias are shown. Conductive via 254″ makes contact to the bottom of the shield/shield layer 260″. The bottom layer of the remaining conductive vias 256″ is also shown as having been formed using dotted lines. The shield/shield layer 260″ is also depicted. The back edge 262″ of the shield layer 260″ is configured to be closer to the ABS than are remaining conductive vias. Note that the conductive vias being fabricated are shown as distributed along the cross track direction and the stripe height direction.



FIG. 9B depicts the transducer 250″ after the next shield/shield layer 270″ is formed by another iteration of steps 222-228. Thus, the conductive via 264″ making contact to shield layer 270″ is shown. The next layer 266″ for the remaining conductive vias is also shown. The back edge 272″ in the shield/shield layer 270″ is also configured to be between the remaining conductive vias and the ABS. The location of the back edge of the shield 260″ is shown by a dashed line. The conductive vias 254″ and 264″ only make contact to the corresponding shield/shield layer 260″ and 270″, respectively. The layers 256″ and 266″ for the remaining conductive vias are isolated from the shield/shield layers 260″ and 270″.



FIG. 9C depicts the transducer 250″ after the conductive vias have been formed by multiple iterations of steps 222-228. Thus, shield/shield layers 280″, 282″, 284″ and 286″ have also been formed. Conductive via layers 274″, 281″, 283″ and 285″ have also been formed. The back edges of each of the shield/shield layers 280″, 282″, 284″ and 286″ (shown by dashed lines for layers 280″, 282″ and 284′″) are between subsequent conductive vias and the ABS. The layers 274″, 281″, 283″ and 285″ make electrical contact only to corresponding shield/shield layers 280″, 282″, 284″ and 286″, respectively.


Thus, using the method 220, stacked conductive vias shown in FIGS. 7A-7C, 8A-8C and/or 9A-9C may be formed. The conductive vias/stacks may make electrical contact to the desired shield/shield layer. In addition, these stacked vias may be formed layer by layer. As such, fabrication of the conductive vias and corresponding transducers may be facilitated.



FIG. 10 is an exemplary embodiment of a method 300 for providing shield(s) and monolithic conductive vias in a read transducer including multiple read sensors. For simplicity, some steps may be omitted, interleaved, and/or combined. The method 300 is also described in the context of providing a single recording transducer 110/110′ in the disk drives 100 and 100′ depicted in FIGS. 2-4B. However, the method 300 may be used to fabricate multiple transducers at substantially the same time. The method 300 may also be used to fabricate other transducers including but not limited to any combination of those disclosed herein. The method 300 is also described in the context of particular layers. A particular layer may include multiple materials and/or multiple sub-layers. The method 300 also may start after formation of other portions of the magnetic recording transducer.


Insulating layer(s) 125 below the shield/shield layer being formed are deposited, via step 302. Other structure(s) below the shield/shield layer being formed may also be provided in step 302. A via hole for the conductive via that makes electrical contact to that shield/shield layer is formed, via step 304. Step 304 may include removing portions of multiple layers to provide the via hole that exposes the desired underlying contact. This via hole may then be filled with a conductor, via step 306. Thus, a single conductive via for the appropriate shield/shield layer is formed.


The corresponding shield/shield layer 130/132 is formed, via step 308. In some embodiments, step 308 is performed before step 304. Thus, the via hole may be provided through the shield layer, and then refilled with a conductor. However, in such an embodiment, it is ensured in step 304 that the conductive via provided in step 306 is in electrical contact with the shield/shield layer. Steps 302 through 308 may then be repeated for conductive vias making electrical contact to subsequent layers, via step 310.



FIGS. 11A-11C depict an exemplary embodiment of a portion of a magnetic transducer 350 during fabrication using the method 300. For clarity, only shield/shield layers and conductive vias are shown. FIGS. 11A-11C are not to scale. The transducer 350 is analogous to the read transducers 110 and 110′. FIG. 11A depicts the transducer 350 after steps 302-308 have been carried out. Thus, underlying pads 352 for the conductive vias are shown. The shield/shield layer 360 is also depicted. Conductive via 354 makes contact to the bottom of the shield/shield layer 360. Note that the conductive vias being fabricated are shown as distributed along the cross track direction. However, in other embodiments, the conductive vias may be distributed along the stripe height direction or along both the stripe height and cross track directions.



FIG. 11B depicts the transducer 350 after the next shield/shield layer 370 is formed using a second iteration of steps 302-308 through step 310. Thus, the conductive via 364 making contact to shield layer 370 is shown. Note that an aperture has been formed in the shield layer 360 to accommodate this conductive via 364 and ensure that the shield layer 360 is electrically isolated from the conductive via 364. An aperture has also been formed in any other layers between the shield/shield layer 370 and the corresponding pad 352 to accommodate this conductive via 364. The conductive vias 354 and 364 only make contact to the corresponding shield/shield layer 360 and 370, respectively.



FIG. 11C depicts the transducer 350 after the conductive vias have been formed using multiple iterations of steps 302-308. Thus, shield/shield layers 380, 382, 384 and 386 have also been formed. Conductive vias 374, 381, 383 and 385 have also been formed. The conductive vias 374, 381, 383 and 385 make electrical contact only to corresponding shield/shield layers 380, 382, 384 and 386, respectively. Also note that aperture(s)s have been formed in the shield/shield layers 360, 370, 380, 382 and 384 to accommodate conductive vias for subsequent shield/shield layers 380, 382, 384 and 386.



FIGS. 12A-12C depict plan views an exemplary embodiment of a portion of a magnetic transducer 350′ during fabrication using the method 300. For clarity, only shield/shield layers and conductive vias are shown. FIGS. 12A-12C are not to scale. The transducer 350′ is analogous to the read transducers 110 and 110′. FIG. 12A depicts the transducer 350′ after steps 302-308 have been carried out. Thus, underlying pads 352′ for the conductive vias are shown. The shield/shield layer 360′ is also depicted. Conductive via 354′ makes contact to the bottom of the shield/shield layer 360′. Note that the conductive vias being fabricated are shown as distributed along the cross track direction. However, in other embodiments, the conductive vias may be distributed along the stripe height direction or along both the stripe height and cross track directions.



FIG. 12B depicts the transducer 350′ after the next shield/shield layer 370′ is formed using an additional iteration of the steps 302-308. Thus, the conductive via 364′ making contact to shield layer 370′ is shown. A notch in the shield/shield layer 360′ has also been formed during fabrication of the conductive via 364′. This notch is depicted by a dashed line. The conductive vias 354′ and 364′ only make contact to the corresponding shield/shield layer 360′ and 370′, respectively.



FIG. 12C depicts the transducer 350′ after the conductive vias have been formed by multiple iterations of steps 302-308, via step 310. Thus, shield/shield layers 380′, 382′, 384′ and 386′ have also been formed. Conductive vias 374′, 381′, 383′ and 385′ have also been formed. The layers 374′, 381′, 383′ and 385′ make electrical contact only to corresponding shield/shield layers 380′, 382′, 384′ and 386′, respectively. Notches have also been formed in the underlying layers when the monolithic conductive vias 374′, 381′, 383′ and 385′ are fabricated.



FIGS. 13A-13C depict plan views an exemplary embodiment of a portion of a magnetic transducer 350″ during fabrication using the method 300. For clarity, only shield/shield layers and conductive vias are shown. FIGS. 13A-13C are not to scale. The transducer 350″ is analogous to the read transducers 110 and 110′. FIG. 13A depicts the transducer 350″ after steps 302-308 have been carried out. Thus, underlying pads 352″ for the conductive vias are shown. The shield/shield layer 360″ is also depicted. Conductive via 354″ makes contact to the bottom of the shield/shield layer 360″. The back edge 362″ of the shield layer 360″ is configured to be closer to the ABS than are remaining conductive vias to be formed. Note that the conductive vias being fabricated are shown as distributed along the cross track direction and the stripe height.



FIG. 13B depicts the transducer 350″ after the next shield/shield layer 370″ is formed by another iteration of steps 302-308. Thus, the conductive via 364″ making contact to shield layer 370″ is shown. The back edge of the shield/shield layer 370″ is also configured to be between the remaining conductive vias and the ABS. The location of the back edge of the shield 360″ is shown by a dashed line. The conductive vias 354″ and 364″ only make contact to the corresponding shield/shield layer 360″ and 370″, respectively.



FIG. 13C depicts the transducer 350″ after the conductive vias have been formed by multiple iterations of steps 302-308. Thus, shield/shield layers 380″, 382″, 384″ and 386″ have also been formed. Conductive vias 374″, 381″, 383″ and 385″ have also been formed. The back edges of each of the shield/shield layers 380″, 382″, 384″ and 386″ (shown by dashed lines for layers 380″, 382″ and 384′″) are between subsequent conductive vias and the ABS. The conductive vias 374″, 381″, 383″ and 385″ make electrical contact only to corresponding shield/shield layers 380″, 382″, 384″ and 386″, respectively.


Thus, using the method 300, monolithic conductive vias shown in FIGS. 11A-11C, 12A-12C and/or 13A-13C may be formed. The monolithic conductive vias may make electrical contact to the desired shield/shield layer. In addition, these monolithic vias may be for the corresponding shield layer. As such, fabrication of the conductive vias and corresponding transducers may be facilitated

Claims
  • 1. A magnetic read transducer having an air-bearing surface (ABS) and comprising: a first read shield;a first read sensor;a shield having a top surface and a bottom surface opposite to the top surface, the bottom surface facing the first read sensor;a second read sensor, the shield residing between the first read sensor and the second read sensor;a second read shield, the first read sensor, the second read sensor and the shield residing between the first read shield and the second read shield; anda conductive via for providing electrical contact to the shield, the conductive via being insulated from the first read shield and the second read shield and contacting the bottom surface of the shield.
  • 2. The magnetic read transducer of claim 1 further comprising: a third read sensor between the second read shield and the second read sensor;a second shield having a second shield top surface and a second shield bottom surface opposite to the second shield top surface, the second shield bottom surface facing the second read sensor, the second shield residing between the third read sensor and the second read sensor; anda second conductive via for providing electrical contact to the second shield, the second conductive via being insulated from the first read shield, the second read shield and the shield, the second conductive via contacting the second shield bottom surface.
  • 3. The magnetic read transducer of claim 2 wherein the shield has a notch therein, the second conductive via passing through the notch.
  • 4. The magnetic read transducer of claim 3 wherein the second read shield includes a second read shield bottom facing the third read sensor, the magnetic read transducer further comprising: a second read shield conductive via for providing electrical contact to the second read shield, the second read shield conductive via being insulated from the first read shield, the shield and the second shield, the second read shield conductive via contacting a second read shield bottom surface; andwherein the second shield has a second notch therein, the second read shield conductive via passing through the second notch.
  • 5. The magnetic read transducer of claim 2 wherein the shield has a back surface opposite to the ABS and the second shield has a second back surface opposite to the ABS, the first back surface being closer to the ABS than the second back surface, the second conductive via residing between the first back surface and the second back surface.
  • 6. The magnetic read transducer of claim 2 wherein the conductive via is a first distance from the ABS and the second conductive via is a second distance from the ABS, the second distance being different from the first distance.
  • 7. The magnetic read transducer of claim 2 wherein the conductive via and the second conductive via are distributed along a cross track direction.
  • 8. The magnetic read transducer of claim 2 further wherein the conductive via is a monolithic structure.
  • 9. The magnetic read transducer of claim 2 wherein the conductive via is a stacked via including a plurality of conductive layers.
  • 10. The magnetic read transducer of claim 1 wherein the shield includes a first shield layer, a second shield layer and an insulating layer between the first shield layer and the second shield layer, the first shield layer residing between the first read sensor and the second shield layer, the first shield layer including the bottom surface, the second shield layer including the top surface, the conductive via contacting the first shield layer and being insulated from the second shield layer, the second shield layer having a second bottom surface facing the first shield layer and wherein the magnetic read transducer further includes: a second conductive via for providing electrical contact to the second shield layer, the second conductive via being insulated from the first read shield, the second read shield and the first shield layer, the second conductive via contacting the second bottom surface.
  • 11. The magnetic read transducer of claim 10 wherein the first shield layer has notch therein, the second conductive via passing through the notch.
  • 12. The magnetic read transducer of claim 11 wherein the second read shield includes a second read shield bottom facing the second read sensor, the magnetic read transducer further comprising: a second read shield conductive via for providing electrical contact to the second read shield, the second read shield conductive via being insulated from the first read shield, the first shield layer and the second shield layer, the second read shield conductive via contacting a second read shield bottom surface; andwherein the second shield layer has second notch therein, the second read shield conductive via passing through the second aperture and the second notch.
  • 13. The magnetic read transducer of claim 10 wherein the first shield layer has a first back surface opposite to the ABS and the second shield layer has a second back surface opposite to the ABS, the first back surface being closer to the ABS than the second back surface, the second conductive via residing between the first back surface and the second back surface.
  • 14. The magnetic transducer of claim 10 wherein the conductive via is a first distance from the ABS and the second conductive via is a second distance from the ABS, the second distance being different from the first distance.
  • 15. The magnetic read transducer of claim 10 wherein the conductive via and the second conductive via are distributed along a cross track direction.
  • 16. The magnetic read transducer of claim 10 further wherein the conductive via is a monolithic structure.
  • 17. The magnetic transducer of claim 10 wherein the conductive via includes a stacked via including a plurality of conductive layers.
  • 18. A disk drive comprising: a media;a slider including a magnetic read transducer having an air-bearing surface (ABS), the read transducer including a first read shield, a first read sensor, a shield, a second read sensor, a second read shield, and a conductive via, the shield having a top surface and a bottom surface opposite to the top surface, the bottom surface facing the first read sensor, the shield residing between the first read sensor and the second read sensor, the first read sensor, the second read sensor and the shield residing between the first read shield and the second read shield, the conductive via for providing electrical contact to the shield, the conductive via being insulated from the first read shield and the second read shield and contacting the bottom surface of the shield.
  • 19. A method for providing a magnetic read transducer having an air-bearing surface (ABS), the method comprising: providing a first read shield;providing a first read sensor;providing a shield having a top surface and a bottom surface opposite to the top surface, the bottom surface facing the first read sensor;providing a second read shield, the first read sensor, the second read sensor and the shield residing between the first read shield and the second read shield; andproviding a conductive via for providing electrical contact to the shield, the conductive via being insulated from the first read shield and the second read shield and contacting the bottom surface of the shield.
  • 20. The method of claim 19 further comprising: providing a third read sensor between the second read shield and the second read sensor;providing a second shield having a second shield top surface and a second shield bottom surface opposite to the second shield top surface, the second shield bottom surface facing the second read sensor, the second shield residing between the third read sensor and the second read sensor; andproviding a second conductive via for providing electrical contact to the second shield, the second conductive via being insulated from the first read shield, the second read shield and the shield, the second conductive via contacting the second shield bottom surface.
  • 21. The method of claim 20 further wherein the step of providing the conductive via further includes: forming a via hole in the first read shield and all of at least one layer between shield and the first read shield; andfilling the via hole with a conductive material such that the conductive via is a monolithic structure.
  • 22. The method of claim 20 wherein the step of providing conductive via further includes: forming a via hole in the first read shield when the first read shield is exposed;filling the via hole with a first conductive material when the first read shield is exposed;forming at least one additional via hole aligned with the via hole in all of at least one layer between shield and the first read shield when the at least one layer is exposed; andfilling the at least one additional via hole with at least one conductive material when the at least one layer is exposed such that the conductive via is a stacked via including a plurality of conductive layers.
  • 23. The method of claim 20 wherein the step of providing conductive via further includes: forming at least one via hole in all of at least one layer between shield and the first read shield when the at least one layer is exposed; andfilling the at least one via hole with at least one conductive material when the at least one layer is exposed such that the conductive via is a stacked via including a plurality of conductive layers.
  • 24. The method of claim 19 wherein the step of providing the shield further includes: providing a first shield layer;providing a second shield layer; andproviding an insulating layer between the first shield layer and the second shield layer, the first shield layer residing between the first read sensor and the second shield layer, the first shield layer including the bottom surface, the second shield layer including the top surface, the conductive via contacting the first shield layer and being insulated from the second shield layer, the second shield layer having a second bottom surface facing the first shield layer and wherein the method further includes:providing a second conductive via for providing electrical contact to the second shield layer, the second conductive via being insulated from the first read shield, the second read shield and the first shield layer, the second conductive via contacting the second bottom surface.
  • 25. The method of claim 24 further wherein the step of providing the conductive via further includes: forming a via hole in the first read shield and all of at least one layer between shield and the first read shield; andfilling the via hole with a conductive material such that the conductive via is a monolithic structure.
  • 26. The method of claim 24 wherein the step of providing conductive via further includes: forming a via hole in the first read shield when the first read shield is exposed;filling the via hole with a first conductive material when the first read shield is exposed;forming at least one additional via hole aligned with the via hole in all of at least one layer between shield and the first read shield when the at least one layer is exposed; andfilling the at least one additional via hole with at least one conductive material such that the conductive via is a stacked via including a plurality of conductive layers.
  • 27. The method of claim 24 wherein the step of providing conductive via further includes: forming at least one via hole aligned with the via hole in all of at least one layer between shield and the first read shield when the at least one layer is exposed; andfilling the at least one via hole with at least one conductive material when the at least one layer is exposed such that the conductive via is a stacked via including a plurality of conductive layers.
CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims priority to provisional U.S. Patent Application Ser. No. 61/865,675, filed on Aug. 14, 2013, which is hereby incorporated by reference in its entirety.

US Referenced Citations (643)
Number Name Date Kind
4012781 Lin Mar 1977 A
5229901 Mallary Jul 1993 A
5270892 Naberhuis Dec 1993 A
5309305 Nepela et al. May 1994 A
5388014 Brug et al. Feb 1995 A
5684658 Shi et al. Nov 1997 A
5696654 Gill et al. Dec 1997 A
5721008 Huang et al. Feb 1998 A
5796535 Tuttle et al. Aug 1998 A
5831888 Glover Nov 1998 A
5963400 Cates et al. Oct 1999 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
6071007 Schaenzer et al. Jun 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
6104562 Ottesen et al. 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
6154335 Smith et al. Nov 2000 A
6157510 Schreck et al. Dec 2000 A
6160684 Heist et al. Dec 2000 A
6163426 Nepela et al. Dec 2000 A
6166891 Lederman et al. Dec 2000 A
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
6191925 Watson 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
6216242 Schaenzer 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
6271998 Coehoorn 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
6311551 Boutaghou Nov 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
6362528 Anand Mar 2002 B2
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
6449131 Guo et al. Sep 2002 B2
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
6496333 Han et al. Dec 2002 B1
6496334 Pang et al. Dec 2002 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
6674618 Engel et al. Jan 2004 B2
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
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
6724569 Chen et al. Apr 2004 B1
6724572 Stoev et al. Apr 2004 B1
6729015 Matono et al. May 2004 B2
6735850 Gibbons et al. May 2004 B1
6737281 Dang et al. May 2004 B1
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
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
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
6842312 Alstrin et al. Jan 2005 B1
6859343 Alfoqaha et al. Feb 2005 B1
6859997 Tong et al. Mar 2005 B1
6861756 Saito et al. Mar 2005 B2
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
6888253 Rogers et al. May 2005 B1
6888704 Diao et al. May 2005 B1
6891702 Tang May 2005 B1
6894871 Alfoqaha et al. May 2005 B2
6894877 Crue, Jr. et al. May 2005 B1
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
6947258 Li Sep 2005 B1
6950266 McCaslin et al. Sep 2005 B1
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
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
7092195 Liu et al. Aug 2006 B1
7106549 Asakura 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
7133253 Seagle et al. Nov 2006 B1
7134185 Knapp et al. Nov 2006 B1
7154715 Yamanaka et al. Dec 2006 B2
7170725 Zhou et al. Jan 2007 B1
7177117 Jiang et al. Feb 2007 B1
7193807 Liikanen et al. Mar 2007 B1
7193815 Stoev et al. Mar 2007 B1
7196880 Anderson et al. Mar 2007 B1
7199974 Alfoqaha Apr 2007 B1
7199975 Pan Apr 2007 B1
7211339 Seagle et May 2007 B1
7212384 Stoev et al. May 2007 B1
7238292 He et al. Jul 2007 B1
7239478 Sin et al. Jul 2007 B1
7248431 Liu et al. Jul 2007 B1
7248433 Stoev et al. Jul 2007 B1
7248449 Seagle Jul 2007 B1
7259927 Harris Aug 2007 B2
7271970 Tsuchiya Sep 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
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
7315072 Watanabe Jan 2008 B2
7318947 Park 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
7371152 Newman May 2008 B1
7372168 Wu et al. May 2008 B2
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
7405907 Raastad Jul 2008 B2
7408730 Yamagishi Aug 2008 B2
7417832 Erickson et al. Aug 2008 B1
7419891 Chen et al. Sep 2008 B1
7428124 Song et al. Sep 2008 B1
7430098 Song et al. Sep 2008 B1
7436620 Kang et al. Oct 2008 B1
7436632 Li et al. Oct 2008 B2
7436638 Pan Oct 2008 B1
7440220 Kang et al. Oct 2008 B1
7443632 Stoev et al. Oct 2008 B1
7444740 Chung et al. Nov 2008 B1
7493688 Wang et al. Feb 2009 B1
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
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
7583466 Kermiche et al. Sep 2009 B2
7595967 Moon et al. Sep 2009 B1
7639457 Chen et al. Dec 2009 B1
7660080 Liu et al. Feb 2010 B1
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
7785666 Sun et al. Aug 2010 B1
7796356 Fowler et al. Sep 2010 B1
7800858 Bajikar et al. Sep 2010 B1
7819979 Chen et al. Oct 2010 B1
7829264 Wang et al. Nov 2010 B1
7846643 Sun et al. Dec 2010 B1
7855854 Hu et al. Dec 2010 B2
7868362 Randazzo et al. Jan 2011 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
7916426 Hu et al. Mar 2011 B2
7918013 Dunn et al. Apr 2011 B1
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
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
8116043 Leng et al. Feb 2012 B2
8116171 Lee Feb 2012 B1
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
8139301 Li et al. 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
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
8208228 Maat 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
8233248 Li et al. Jul 2012 B1
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
8264797 Emley Sep 2012 B2
8264798 Guan et al. Sep 2012 B1
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
8289821 Huber Oct 2012 B1
8291743 Shi et al. Oct 2012 B1
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
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
8384220 Saito 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
8711518 Zeng et al. Apr 2014 B1
8711528 Xiao et al. Apr 2014 B1
8717709 Shi et al. May 2014 B1
8720044 Tran et al. May 2014 B1
8721902 Wang et al. May 2014 B1
8724259 Liu et al. May 2014 B1
8749790 Tanner et al. Jun 2014 B1
8749920 Knutson et al. Jun 2014 B1
8753903 Tanner et al. Jun 2014 B1
8760807 Zhang et al. Jun 2014 B1
8760818 Diao et al. Jun 2014 B1
8760819 Liu et al. Jun 2014 B1
8760822 Li et al. Jun 2014 B1
8760823 Chen et al. Jun 2014 B1
8763235 Wang et al. Jul 2014 B1
8780498 Jiang et al. Jul 2014 B1
8780505 Xiao Jul 2014 B1
8786983 Liu et al. Jul 2014 B1
8790524 Luo et al. Jul 2014 B1
8790527 Luo et al. Jul 2014 B1
8792208 Liu et al. Jul 2014 B1
8792312 Wang et al. Jul 2014 B1
8793866 Zhang et al. Aug 2014 B1
8797680 Luo et al. Aug 2014 B1
8797684 Tran et al. Aug 2014 B1
8797686 Bai et al. Aug 2014 B1
8797692 Guo et al. Aug 2014 B1
8813324 Emley et al. Aug 2014 B2
8891207 Li et al. Nov 2014 B1
20100290157 Zhang et al. Nov 2010 A1
20110086240 Xiang et al. Apr 2011 A1
20120111826 Chen et al. May 2012 A1
20120216378 Emley et al. Aug 2012 A1
20120237878 Zeng et al. Sep 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
20140154529 Yang et al. Jun 2014 A1
20140175050 Zhang et al. Jun 2014 A1
Non-Patent Literature Citations (1)
Entry
Shaoping Li, et al., U.S. Appl. No. 13/928,799, filed Jun. 27, 2013, 27 pp.
Provisional Applications (1)
Number Date Country
61865675 Aug 2013 US