Magnetic reader having a nonmagnetic insertion layer for the pinning layer

Abstract
A method and system provide a magnetic read apparatus. The magnetic read apparatus includes a read sensor. The read sensor includes a pinning layer, a nonmagnetic insertion layer and a pinned layer. The nonmagnetic insertion layer has a location selected from a first location and a second location. The first location is between the pinned layer and the pinning layer. The second location is within the pinning layer.
Description
BACKGROUND


FIG. 1 depicts an air-bearing surface (ABS) view of a conventional read transducer used in magnetic recording technology applications. The conventional read transducer 10 includes shields 12 and 18, insulator 14, magnetic bias structures 16, and sensor 20. The read sensor 20 is typically a giant magnetoresistive (GMR) sensor or tunneling magnetoresistive (TMR) sensor. The read sensor 20 includes an antiferromagnetic (AFM) layer 22, a pinned layer 24, a nonmagnetic spacer layer 26, and a free layer 28. Also shown is a capping layer 30. In addition, seed layer(s) may be used. The free layer 28 has a magnetization sensitive to an external magnetic field. Thus, the free layer 28 functions as a sensor layer for the magnetoresistive sensor 20. If the sensor 20 is to be used in a current perpendicular to plane (CPP) configuration, then current is driven in a direction substantially perpendicular to the plane of the layers 22, 24, 26, and 28. Conversely, in a current-in-plane (CIP) configuration, then conductive leads (not shown) would be provided on the magnetic bias structures 16. The magnetic bias structures 16 are used to magnetically bias the free layer 28. The pinned layer 26 adjoins, or shares an interface, with the AFM layer 22. This allows for the pinned layer 26 magnetic moment to be exchange coupled with the magnetic moments AFM layer 22. Consequently, the pinned layer magnetic moment is fixed, or pinned, using the AFM layer 22.


Although the conventional transducer 10 functions, there are drawbacks. In particular, the read sensor 20 may be subject to noise. For example, there may be instabilities in the orientation of the pinned layer magnetic moment with respect to the free layer magnetic moment. The conventional read sensor 20 may not thus adequately read high density media.





BRIEF DESCRIPTION OF SEVERAL VIEWS OF THE DRAWINGS


FIG. 1 depicts an ABS view of a conventional magnetic recording read transducer.



FIGS. 2A-2B depict side and ABS views of an exemplary embodiment of a portion of a magnetic read apparatus.



FIG. 3A-3B are graphs depicting the magnetic moment versus field and the ratio of the exchange field to the coercivity of the pinned layer versus thickness of the magnetic insertion layer.



FIG. 4 depicts another exemplary embodiment of a portion of a magnetic read sensor.



FIG. 5 depicts another exemplary embodiment of a portion of a magnetic read sensor.



FIG. 6 depicts another exemplary embodiment of a portion of a magnetic read sensor.



FIG. 7 is flow chart depicting an exemplary embodiment of a method for providing a magnetic recording read apparatus.



FIG. 8 is flow chart depicting another exemplary embodiment of a method for providing a magnetic recording read transducer.





DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS


FIGS. 2A-2B depict side and ABS views of an exemplary embodiment of a portion of a magnetic recording apparatus 100. For clarity, FIGS. 2A-2B are not to scale. Further, only a portion of the components of the magnetic apparatus 100 are depicted. The magnetic recording apparatus 100 depicted is a disk drive including media 101 and a slider 102 having a writer 104 and a read transducer 110 fabricated thereon. The write transducer 104 includes at least a write pole 106 and coil(s) 108 for energizing the pole 106. The write transducer 104 may be a perpendicular magnetic recording (PMR) writer, a heat assisted magnetic recording (HAMR) writer or another writer. In other embodiments, the write transducer 104 might be omitted.


The read transducer 110 includes a read sensor 120 and may include soft magnetic shields 112 and 114. The shields 112 and 114 may be formed of NiFe or another soft magnetic material. The read transducer 110 may also include insulating layer 116 and magnetic bias structures 118. The insulating layer 116 separates the magnetic bias structures 118 from the read sensor 120 and, in the embodiment shown, from the shield 112. The magnetic bias structures 118 may be soft magnetic bias structures, hard magnetic bias structures and/or other magnetic bias structures. In other embodiments, other structures may be included and/or structures 112, 114, 116 and/or 118 may be omitted.


The read sensor 120 includes at least a pinning layer 130, a nonmagnetic insertion layer 140 and a pinned layer 150. In the embodiment shown, the read sensor 120 also includes a nonmagnetic spacer layer 160 and a free layer 170. The nonmagnetic spacer layer may be a conductor, such as Cu, or an insulating tunneling barrier layer, such as crystalline MgO. Thus, the sensor 120 may be a GMR sensor or a TMR sensor.


The pinning layer 130 is used to fix, or pin, the magnetic moment of the pinned layer 150. The pinning layer 130 may thus be an antiferromagnetic (AFM) layer 130. For example, the pinning layer 130 might be an IrMn layer, a PtMn layer, an FeMn layer or an analogous structure. The pinned layer 150 is ferromagnetic and may include sublayers that are magnetic and/or nonmagnetic. Note that in some embodiments, a nonmagnetic layer (not shown) and a ferromagnetic layer (not shown) may be between the pinned layer 150 and the nonmagnetic spacer layer 160. In some such embodiments, the magnetic moments of the pinned layer 150 and the additional ferromagnetic layer may be antiferromagnetically coupled through the nonmagnetic layer. Thus, the pinned layer 150 may be part of a structure such as a synthetic antiferromagnetic (SAF) structure.


The nonmagnetic insertion layer 140 has a location selected from a first location and a second location. The first location, shown in the embodiment depicted in FIG. 2B, is between the pinning layer 130 and the pinned layer 150. In some embodiments, the nonmagnetic insertion layer 140 adjoins both the pinning layer 130 and the pinned layer 150. Thus, the nonmagnetic insertion layer 140 may share one interface with the pinning layer 130 and the opposite interface with the pinned layer 150. The second location is within the pinning layer 130. In an alternate embodiment, multiple nonmagnetic insertion layers could be included. In such an embodiment, one insertion layer would be in the first location (between the layers 130 and 150) and another insertion layer would be in the second location (within the layer 150). In some embodiments, the nonmagnetic insertion layer 140 includes at least one of Ag, Mg, Mn, Ir, Pt, Cr, Ti, Si, C, Al, Ru and Au. In some such embodiments, the nonmagnetic insertion layer 140 consists of Ag, Mg, Mn, Ir, Pt, Cr, Ti, Si, C, Al, Ru and/or Au. The nonmagnetic insertion layer 140 may also be desired to be thin. In some embodiments, therefore, the thickness of the nonmagnetic insertion layer 140 may be at least one Angstrom and not more than five Angstroms in some embodiments. For example, the thickness of the nonmagnetic insertion layer 140 may be at least one Angstroms and not more than three Angstroms. The nonmagnetic insertion layer 140 may thus be a dusting layer. In some embodiments, the nonmagnetic insertion layer 140 may be discontinuous.


The nonmagnetic insertion layer 140 is configured to affect the magnetic coupling between the pinning layer 130 and the pinned layer 150. This effect may be seen in FIGS. 3A-3B. FIGS. 3A and 3B are graphs 200 and 210, respectively, depicting the magnetic moment versus field for the pinned layer 150 and the ratio of the exchange field to the coercivity versus the thickness of the insertion layer 140. FIGS. 3A-3B are not to scale and are for explanatory purposes only. Thus, actual data is not meant to be represented in the graphs 200 and 210.


As can be seen in FIG. 3A, the magnetic moment of the pinned layer 150 exhibits a hysteresis loop 202 with respect to magnetic field. The hysteresis loop 202 is shifted from being centered at a zero applied magnetic field because of the magnetic coupling between the pinning layer 130 and the pinned layer 150. The shift in the center of the hysteresis loop is the exchange field, Hex, due to the coupling between the pinning layer 130 and the pinned layer 150. The coercivity, Hcp, relates to the applied field which will cause the magnetic moment of the pinned layer 150 to go to zero as part of a transition from a positive moment to a negative moment or vice versa. Because the hysteresis loop is shifted, the coercivity is based on the width of the loop (2*Hcp=width of loop). The coercivity is a measure of the fraction of unstable grains in the pinning layer 130.


The ratio of the exchange field to the coercivity (Hex/Hcp) may be considered both a measure of the strength and stability of the magnetic coupling between the pinning layer 130 and the pinned layer 150 and a measure of the fraction of unstable grains in the pinning layer 130. As can be seen in the graph 210 of FIG. 3B, the use of the nonmagnetic insertion layer 140 changes this ratio. Curves 212, 214 and 216 depict the ratio Hex/Hcp versus insertion layer thickness for various materials. Note that a zero thickness for the nonmagnetic insertion layer 140 means that no nonmagnetic insertion material is present. Thus, the curves 212, 214 and 216 meet at a zero insertion layer thickness. Curve 212 is the generally expected result of adding the nonmagnetic insertion layer 140, particularly between the pinned layer 150 and the pinning layer 130. For the material corresponding to the curve 212, the presence of any nonmagnetic material reduces the exchange coupling. Such a curve is typical for the insertion of a nonmagnetic material between the layers 130 and 150. Thus, for most materials, the relationship between insertion layer thickness and Hex/Hcp would follow the curve 212. Curves 214 and 216, in contrast, indicate that the ratio of Hex to Hcp may actually increase for small thicknesses of certain materials. For some such materials, the exchange field may increase for small thicknesses (e.g. less than ten Angstroms) while the coercivity decreases or remains constant. Alternatively, the coercivity may decrease and the exchange field may be constant for the small thicknesses. Other combinations of possibilities result in a maximum in Hex/Hcp that occurs at a nonzero thickness of the nonmagnetic insertion layer 140. Thus, for appropriate selection of materials and location, Hex/Hcp increases or remains constant for nonzero insertion layer thicknesses. Materials such as Ag, Mg, Mn, Ir, Pt, Cr, Ti, Si, C, Al, Ru and/or Au used as the insertion layer allow for an increase (or constant) Hex/Hcp for the pinned layer 150 and pinning layer 130 at small thicknesses of nonmagnetic insertion layer. For larger thicknesses of the nonmagnetic insertion layer 140, the magnetic coupling between the layers 130 and 150 decreases. Thus, the nonmagnetic insertion layer 140 is configured such that the Hex/Hcp for the pinned layer 150 has a maximum for a nonzero thickness of the insertion layer 140. Stated differently, the nonmagnetic insertion layer 140 is configured such that Hex/Hcp increases or remains constant for some small thicknesses of the nonmagnetic insertion layer 140.


It is believed that the nonmagnetic insertion layer 140 operates in the following manner. However, the benefits and use of the magnetic devices described herein are independent of a particular physical mechanism. Because the nonmagnetic insertion layer 140 is thin and may be made of particular materials, it is believed that the materials in the nonmagnetic insertion layer 140 migrate to the grain boundaries of the grains of the pinning layer 140 during fabrication. Thus, although depicted as a single layer, the nonmagnetic insertion layer 140 may be discontinuous or reside only in certain areas (e.g. grain boundaries at and near the interface of the pinning layer 130. The presence of the nonmagnetic insertion layer 140 at the grain boundaries of smaller, less stable grains may decouple these grains from the pinned layer 150. Thus, if the magnetic moment of the pinned layer 150 switches direction, the less stable grains of the pinning layer 130 may be less likely to change direction. Thus, these less stable grains are thus less likely to provide a magnetic bias in a direction opposite to the desired direction of magnetization. The pinned layer 150 magnetic moment may more readily return to the desired direction. The coercivity of the pinned layer 150 may thus be reduced. The stability of the magnetic moment of the pinned layer 150 may be enhanced. Stated differently, the coupling between the pinning layer 130 and the pinned layer 150 that pins the magnetic moment of the pinned layer 150 in the desired direction may be improved.


Regardless of the physical mechanism, the ratio of the exchange field and the coercivity may be improved. Consequently, the stability of the coupling between the pinned layer 150 and the pinning layer 130 may be enhanced. Noise due to instabilities in the magnetic moment of the pinned layer 130 may thus be removed. Performance of the magnetic device may thereby be improved.



FIG. 4 depicts another embodiment of a magnetic read sensor 120′. For clarity, FIG. 4 is not to scale. The read sensor 120′ may be part of a read transducer and/or magnetic recording apparatus such as the read transducer 110 and magnetic recording apparatus 100. The transducer of which the read sensor 120′ may be a part is part of a disk drive having a media, a slider and the head coupled with the slider. The read sensor 120′ corresponds to the read sensor 120. Consequently, analogous components are labeled similarly. For example, the read sensor 120′ includes a pinning/AFM layer 130, a nonmagnetic insertion layer 140′, a pinned layer 150, a nonmagnetic spacer or tunneling barrier layer 160 and a free layer 170 that are analogous to the a pinning/AFM layer 130, the nonmagnetic insertion layer 140, the pinned layer 150, the nonmagnetic spacer or tunneling barrier layer 160 and the free layer 170 that are part of the read sensor 120 and thus part of the magnetic recording apparatus 100. Thus, the components 120′, 130, 140′, 150, 160 and 170 have a similar structure and function to the components 120, 130, 140, 150, 160 and 170, respectively, depicted in FIGS. 2A-2B. Thus, the nonmagnetic insertion layer 140′ is configured such that Hex/Hcp increases or remains constant for some small thicknesses of the nonmagnetic insertion layer 140′. In some embodiments, the nonmagnetic insertion layer 140′ includes at least one of Ag, Mg, Mn, Ir, Pt, Cr, Ti, Si, C, Al, Ru and Au. In some such embodiments, the nonmagnetic insertion layer 140′ consists of Ag, Mg, Mn, Ir, Pt, Cr, Ti, Si, C, Al, Ru and/or Au. The nonmagnetic insertion layer 140′ may also be desired to be thin. The nonmagnetic insertion layer 140′ may have a thickness of not more than five Angstroms. In some such embodiments, the thickness of the nonmagnetic insertion layer 140′ may be not more than three Angstroms. The nonmagnetic insertion layer 140′ may also have a thickness of at least one Angstrom.


In the embodiment shown in FIG. 4, the nonmagnetic insertion layer 140′ is explicitly discontinuous. In some embodiments, the nonmagnetic insertion layer 140′ at least one Angstrom thick. Other thicknesses are, however, possible. In the embodiment shown, the nonmagnetic insertion layer 140′ is in the first location: between the pinned layer 150 and the pinning layer 130. Also in the embodiment shown, the nonmagnetic insertion layer 140′ shares interfaces with the pinning layer 130 and an opposite interface with the pinned layer 150. Note that in some embodiments, the nonmagnetic insertion layer 140′ may reside at the grain boundaries of the pinning layer 130. Thus, the top surface of the nonmagnetic insertion layer 140′ may be substantially coplanar with the top surface of the pinning layer 130. The nonmagnetic insertion layer 140′ is, however, still considered to be at the first location: between the pinned layer 150 and the pinning layer 130. In another embodiment, the nonmagnetic insertion layer 140′ might be located within the pinning layer 130.


The read sensor 120′ shares the benefits of the read sensor 120. The use of the nonmagnetic insertion layer 140′ may allow for a maximum in the Hex/Hcp for nonzero thicknesses of the nonmagnetic insertion layer 140′. Thus, the coupling between the pinning layer 130 and pinned layer 150 may be improved. The improved stability in the coupling between the pinned layer 150 and the pinning layer 130 may reduce noise during operation of the read sensor 120′.



FIG. 5 depicts another embodiment of a magnetic read sensor 120″. For clarity, FIG. 5 is not to scale. The read sensor 120″ may be part of a read transducer and/or magnetic recording apparatus such as the read transducer 110 and magnetic recording apparatus 100. The transducer of which the read sensor 120″ may be a part is part of a disk drive having a media, a slider and the head coupled with the slider. The read sensor 120″ corresponds to the read sensor(s) 120 and/or 120′. Consequently, analogous components are labeled similarly. For example, the read sensor 120″ includes a pinning/AFM layer 130, a nonmagnetic insertion layer 140/140′, a pinned layer 150, a nonmagnetic spacer or tunneling barrier layer 160 and a free layer 170 that are analogous to the a pinning/AFM layer 130, the nonmagnetic insertion layer 140/140′, the pinned layer 150, the nonmagnetic spacer or tunneling barrier layer 160 and the free layer 170 that are part of the read sensor 120 and thus part of the magnetic recording apparatus 100. Thus, the components 120′, 130, 140/140′, 150, 160 and 170 have a similar structure and function to the components 120, 130, 140/140′, 150, 160 and 170, respectively, depicted in FIGS. 2A-2B and 4. Thus, the nonmagnetic insertion layer 140/140′ is configured such that Hex/Hcp increases or remains constant for some small thicknesses of the nonmagnetic insertion layer 140/140′. In some embodiments, the nonmagnetic insertion layer 140/140′ includes at least one of Ag, Mg, Mn, Ir, Pt, Cr, Ti, Si, C, Al, Ru and Au. In some such embodiments, the nonmagnetic insertion layer 140/140′ consists of Ag, Mg, Mn, Ir, Pt, Cr, Ti, Si, C, Al, Ru and/or Au. The nonmagnetic insertion layer 140/140′ may also be desired to be thin. The nonmagnetic insertion layer 140/140′ may have a thickness of not more than five Angstroms. In some such embodiments, the thickness of the nonmagnetic insertion layer 140/140′ may be not more than three Angstroms. The nonmagnetic insertion layer 140/140′ may also have a thickness of at least one Angstrom.


In the embodiment shown in FIG. 5, the read sensor 120″ includes a nonmagnetic layer 180 and a reference layer 190. The nonmagnetic layer 180 is conductive and may include a material such as Ru. The reference layer 190 is ferromagnetic and may include sublayers. The reference layer 190 and the pinned layer 150 are coupled through the nonmagnetic layer 180. For example, the coupling may be an RKKY coupling. Thus, the layers 150, 180 and 190 form a synthetic antiferromagnet (SAF).


The read sensor 120″ shares the benefits of the read sensor(s) 120/120′. The use of the nonmagnetic insertion layer 140/140′ may allow for a maximum in the Hex/Hcp for nonzero thicknesses of the nonmagnetic insertion layer 140/140′. Thus, the coupling between the pinning layer 130 and pinned layer 150 may be improved. The improved stability in the coupling between the pinned layer 150 and the pinning layer 130 may reduce noise during operation of the read sensor 120″.



FIG. 6 depicts another embodiment of a magnetic read sensor 120″. For clarity, FIG. 6 is not to scale. The read sensor 120′″ may be part of a read transducer and/or magnetic recording apparatus such as the read transducer 110 and magnetic recording apparatus 100. The transducer of which the read sensor 120′″ may be a part is part of a disk drive having a media, a slider and the head coupled with the slider. The read sensor 120′″ corresponds to the read sensor(s) 120, 120′ and/or 120″. Consequently, analogous components are labeled similarly. For example, the read sensor 120′″ includes a pinning/AFM layer 130′, a nonmagnetic insertion layer 140/140′, a pinned layer 150, a nonmagnetic spacer or tunneling barrier layer 160 and a free layer 170 that are analogous to the a pinning/AFM layer 130, the nonmagnetic insertion layer 140/140′, the pinned layer 150, the nonmagnetic spacer or tunneling barrier layer 160 and the free layer 170 that are part of the read sensor 120 and thus part of the magnetic recording apparatus 100. The read sensor 120′″ also may include optional reference layer 190 and optional nonmagnetic layer 180. The pinned layer 150′, optional nonmagnetic spacer layer 180 and optional reference layer 190′ may form an optional SAF 192.


Thus, the components 120′″, 130′, 140/140′, 150, 160, 170, 180, and 170 have a similar structure and function to the components 120/120′/120″, 130, 140/140′, 150, 160 and 170, respectively, depicted in FIGS. 2A-2B and 4. Thus, the nonmagnetic insertion layer 140/140′ is configured such that Hex/Hcp increases or remains constant for some small thicknesses of the nonmagnetic insertion layer 140/140′. In some embodiments, the nonmagnetic insertion layer 140/140′ includes at least one of Ag, Mg, Mn, Ir, Pt, Cr, Ti, Si, C, Al, Ru and Au. In some such embodiments, the nonmagnetic insertion layer 140/140′ consists of Ag, Mg, Mn, Ir, Pt, Cr, Ti, Si, C, Al, Ru and/or Au. The nonmagnetic insertion layer 140/140′ may also be desired to be thin. The nonmagnetic insertion layer 140/140′ may have a thickness of not more than five Angstroms. In some such embodiments, the thickness of the nonmagnetic insertion layer 140/140′ may be not more than three Angstroms. The nonmagnetic insertion layer 140/140′ may also have a thickness of at least one Angstrom.


In the embodiment shown in FIG. 6, the nonmagnetic insertion layer 140/140′ is explicitly within the pinning layer 130′. Thus the pinning layer 130′ includes a pinning layer A 132 and a pinning layer 134 between which is the nonmagnetic insertion layer 140/140′. Although depicted as midway through the pinning layer 130′, the nonmagnetic insertion layer 140/140′ may reside elsewhere. For example, the nonmagnetic insertion layer 140/140′ may be closer to the interface between the layers 130′ and 150′ than to the bottom surface of the pinning layer 130′. Further, even if the nonmagnetic insertion layer 140/140′ is deposited in the middle of the AFM layer 130′ as shown, the nonmagnetic insertion layer 140/140′ may migrate during fabrication of the read sensor 120′″. Thus, the nonmagnetic insertion layer 140/140′ may be closer to the pinned layer 150 and may or may not be continuous.


The read sensor 120′″ shares the benefits of the read sensor(s) 120/120′/120′. The use of the nonmagnetic insertion layer 140/140′ may allow for a maximum in the Hex/Hcp for nonzero thicknesses of the nonmagnetic insertion layer 140/140′. Thus, the coupling between the pinning layer 130′ and pinned layer 150 may be improved. The improved stability in the coupling between the pinned layer 150 and the pinning layer 130′ may reduce noise during operation of the read sensor 120″.


The read sensors 120, 120′, 120″ and 120′″ have been shown in various configurations to highlight particular features, such as differences in geometries. One of ordinary skill in the art will readily recognize that two or more of these features may be combined in various manners consistent with the method and system described herein that are not explicitly depicted in the drawings.



FIG. 7 is an exemplary embodiment of a method 300 for providing a read transducer. For simplicity, some steps may be omitted, interleaved, combined, have multiple substeps and/or performed in another order unless otherwise specified. The method 300 is described in the context of providing a magnetic recording apparatus 100, transducer 110 and read sensor 100. However, the method 300 may be used in fabricating the read sensor 120, 120′, 120″ and/or 120″. The method 300 may be used to fabricate multiple magnetic read heads at substantially the same time. The method 300 may also be used to fabricate other magnetic recording transducers. 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 is described in the context of a disk drive. However, the method may be used in other applications employing a magnetoresistive and bias structures. The method 300 also may start after formation of other portions of the magnetic recording transducer.


The bottom shield 112 is provided, via step 302. Step 302 may include depositing a magnetic material, such as NiFe and patterning the shield.


The read sensor 120 is provided, via step 304. Step 304 may include depositing a stack of layers for the read sensor 120 and defining the read sensor in the cross-track and stripe height directions. Further, the nonmagnetic insertion layer 140 is provided in the first or second location. Thus, the nonmagnetic insertion layer 140 may be placed between the pinned layer 150 and the pinning layer 140 or may be placed within the AFM. Thus, the read sensor 120, 120′, 120″ or 120′″ may be provided.


The side bias structures 118 are provided, via step 306. Step 306 is performed after the read sensor 120 is defined in the cross-track direction. Thus, at least part of step 304 is performed before step 306. Step 306 may include depositing the insulating layer 116, depositing the material(s) for the magnetic bias structures 118 and depositing a top nonmagnetic layer. A mill step and planarization, such as a chemical mechanical planarization (CMP) may also be performed.


The top shield 114 is provided, via step 308. Step 208 may include depositing, planarizing and patterning soft magnetic layer, such as a NiFe layer.


Using the method 300, the transducer 110 and the read sensor 120, 120′, 120″ and/or 120′″ may be fabricated. Thus, the benefits of one or more of the read sensor 120, 120′, 120″ and/or 120′″ may be achieved. Consequently, performance of the magnetic recording apparatus may be improved.



FIG. 8 is an exemplary embodiment of a method 310 for providing a read sensor such as the read sensor 120, 120′, 120″ and/or 120′″. For simplicity, some steps may be omitted, interleaved, combined, have multiple substeps and/or performed in another order unless otherwise specified. The method 310 is described in the context of providing a magnetic recording disk drive 100 and transducer 110. However, the method 310 may be used in fabricating another magnetic recording device. The method 310 may be used to fabricate multiple magnetic read sensors at substantially the same time. The method 310 is also described in the context of particular layers. A particular layer may include multiple materials and/or multiple sub-layers.


The pinning layer 130/130′ is deposited, via step 312. Step 312 may include heating the substrate such that the materials for the pinning layer are deposited above the ambient temperature. For example, the IrMn or other AFM used for the pinning layer 130/130′ may be deposited above room temperature.


The nonmagnetic insertion layer 140/140′ is provided via step 314. Step 314 may include controlling the temperature of the substrate. Thus, the substrate may be heated such that the material(s) for the nonmagnetic insertion layer are deposited at a temperature above the ambient temperature. For example, the nonmagnetic insertion layer 140/140′ may be sputtered above room temperature. In such embodiments, the atoms for the nonmagnetic insertion layer 140/140′ may be more mobile. These atoms may more readily migrate, for example to grain boundaries of the pinning layer 130/130′. In other embodiments, step 314 may include cooling the substrate such that the nonmagnetic insertion layer 140/140′ is deposited at temperatures below the ambient temperature. For example, the substrate may be cooled (e.g. via water cooling, liquid nitrogen cooling or physical connection to another heat sink) below the ambient temperature during deposition. For example, the material(s) for the nonmagnetic insertion layer 140/140′ may be sputtered below room temperature. In such embodiments, the atoms for the nonmagnetic insertion layer may be less likely to migrate. In other embodiments, no attempt may be made to control the temperature of the substrate during deposition. Further, if the pinning layer 130′ is used, then steps 312 and 314 are interleaved such that the nonmagnetic insertion layer 140/140′ is deposited within the pinning layer 130′.


The pinned layer 150 is deposited, via step 316. Step 316 may include depositing multiple ferromagnetic layers. Nonmagnetic layer(s) may also be provided within the pinned layer. In some embodiments, the nonmagnetic layer 180 and reference layer 190 are deposited in steps 320 and 322, respectively.


The nonmagnetic spacer layer 160 is deposited, via step 322. For example, a conductive layer or tunneling barrier layer may be provided in step 322. The free layer 170 is deposited, via step 324. Step 324 may include depositing multiple ferromagnetic layers. Nonmagnetic layer(s) may also be provided within the free layer 170.


The edges of the read sensor 120, 120′, 120″ and/or 120′″ are defined, via step 324. Step 324 may include providing a mask on the read sensor stack deposited in the previous steps and ion milling the exposed regions. The read sensor 120, 120′, 120″ and/or 120′″ may be defined in the cross-track and stripe height (perpendicular to the ABS) directions. Fabrication of the read sensor may then be completed. For example, anneals, capping layer depositing, and/or other processing steps may be performed.


Using the method 310, the read sensor(s) 120, 120′, 120″ and/or 120′″ may be fabricated. Thus, the benefits of one or more of the read sensor(s) 120, 120′, 120″ and/or 120′″ may be achieved.

Claims
  • 1. A magnetic apparatus comprising: an element comprising a pinning layer, a nonmagnetic insertion layer, and a pinned layer, a location of the nonmagnetic insertion layer selected from a first location between the pinned layer and the pinning layer and a second location within the pinning layer,wherein, in the first location, a top surface of the nonmagnetic insertion layer is substantially coplanar with a top surface of the pinning layer, and wherein the nonmagnetic insertion layer adjoins the pinned layer and the pinning layer, the pinning layer being an antiferromagnetic (AFM) layer.
  • 2. The magnetic apparatus of claim 1 wherein the element further comprises a nonmagnetic spacer layer and a free layer, the nonmagnetic spacer layer residing between the free layer and the pinned layer, the pinned layer being between the free layer and the pinning layer such that the free layer, the nonmagnetic spacer layer, the pinned layer and the pinning layer form a stack.
  • 3. The magnetic apparatus of claim 1 wherein the nonmagnetic insertion layer comprises at least one of Ag, Mg, Mn, Ir, Pt, Cr, Ti, Si, C, Al, Ru and Au.
  • 4. The magnetic apparatus of claim 1 wherein the nonmagnetic insertion layer has a thickness of not more than five Angstroms.
  • 5. The magnetic apparatus of claim 4 wherein the nonmagnetic insertion layer has the thickness of not more than three Angstroms.
  • 6. The magnetic apparatus of claim 4 wherein the nonmagnetic insertion layer has the thickness of at least one Angstrom.
  • 7. The magnetic apparatus of claim 1 further comprising: a bottom shield;a top shield, the element residing between the bottom shield and the top shield; anda side bias structure adjacent to at least one side surface of the element.
  • 8. The magnetic apparatus of claim 1 wherein the nonmagnetic insertion layer is at the first location.
  • 9. The magnetic apparatus of claim 8 wherein the nonmagnetic insertion layer adjoins the pinning layer and the pinned layer adjoins the nonmagnetic insertion layer.
  • 10. The magnetic apparatus of claim 1 wherein the nonmagnetic insertion layer is configured such that a ratio of an exchange field to a coercivity for the pinned layer has a maximum at a nonzero thickness of the nonmagnetic insertion layer.
  • 11. The magnetic apparatus of claim 1 wherein the nonmagnetic insertion layer excludes Mg and Al.
  • 12. A magnetic apparatus comprising: an element comprising a pinning layer, a nonmagnetic insertion layer, and a pinned layer, a location of the nonmagnetic insertion layer selected from a first location between the pinned layer and the pinning layer and a second location within the pinning layer,wherein the nonmagnetic insertion layer is a discontinuous layer.
  • 13. A magnetic apparatus comprising: an element comprising a pinning layer, a nonmagnetic insertion layer, and a pinned layer, the nonmagnetic insertion layer located between the pinned layer and the pinning layer, wherein a top surface of the nonmagnetic insertion layer is substantially coplanar with a top surface of the pinning layer, and wherein the nonmagnetic insertion layer adjoins the pinned layer and the pinning layer;wherein the element further comprises a nonmagnetic layer and a reference layer, the nonmagnetic layer residing between the reference layer and the pinned layer, the reference layer having a reference layer magnetic moment, the pinned layer having a pinned layer magnetic moment, the reference layer magnetic moment being antiferromagnetically coupled with the pinned layer magnetic moment.
  • 14. A disk drive comprising: at least one disk;at least one slider including at least one magnetic transducer comprising a bottom shield, a top shield, and an element between the bottom shield and the top shield, the element comprising an antiferromagnetic (AFM) layer, a nonmagnetic insertion layer, a pinned layer, a nonmagnetic layer, and a free layer, the nonmagnetic layer being between the pinned layer and the free layer, the nonmagnetic insertion layer having a location selected from a first location between the pinned layer and the pinning layer and a second location within the pinning layer, wherein the nonmagnetic insertion layer is a discontinuous layer.
  • 15. The disk drive of claim 14 wherein the nonmagnetic insertion layer excludes Mg and Al.
  • 16. A method for providing a magnetic apparatus comprising: providing an element, wherein providing the element further comprises: providing a pinning layer;providing a nonmagnetic insertion layer; andproviding a pinned layer on the nonmagnetic insertion layer, wherein the nonmagnetic insertion layer is located between the pinned layer and the pinning layer such that a top surface of the nonmagnetic insertion layer is substantially coplanar with a top surface of the pinning layer and, wherein the nonmagnetic insertion layer adjoins the pinned layer and the pinning layer, the pinning layer being an antiferromagnetic (AFM) layer.
  • 17. The method of claim 16 wherein the step of providing the element further comprises: providing a nonmagnetic spacer layer; andproviding a free layer, the nonmagnetic spacer layer residing between the free layer and the pinned layer, the pinned layer being between the free layer and the pinning layer such that the free layer, the nonmagnetic spacer layer, the pinned layer and the pinning layer form a stack.
  • 18. The method of claim 16 wherein the nonmagnetic insertion layer comprises at least one of Ag, Mg, Mn, Ir, Pt, Cr, Ti, Si, C, Al, Ru and Au.
  • 19. The method of claim 16 wherein the nonmagnetic insertion layer has a thickness of at least one Angstrom.
  • 20. The method of claim 16 wherein the step of providing the nonmagnetic insertion layer comprises: depositing the nonmagnetic insertion layer on a heated substrate.
  • 21. The method of claim 16 wherein the step of providing the nonmagnetic insertion layer comprises: depositing the nonmagnetic insertion layer on a cooled substrate.
  • 22. The method of claim 16 wherein the step of providing the pinning layer comprises: depositing the pinning layer on a heated substrate.
  • 23. The method of claim 16 wherein the step of providing the nonmagnetic insertion layer comprises: depositing the nonmagnetic insertion layer directly on the pinning layer; andwherein providing the pinned layer further comprises depositing the pinned layer directly on the nonmagnetic insertion layer.
  • 24. The method of claim 16 wherein the nonmagnetic insertion layer is configured such that a ratio of an exchange field to a coercivity for the pinned layer has a maximum at a nonzero thickness of the nonmagnetic insertion layer.
  • 25. The method of claim 16 wherein the nonmagnetic insertion layer excludes Mg and Al.
  • 26. A magnetic apparatus comprising: an element comprising a pinning layer, a nonmagnetic insertion layer, and a pinned layer, wherein the nonmagnetic insertion layer is located within the pinning layer.
  • 27. A disk drive comprising: at least one disk;at least one slider comprising at least one magnetic transducer comprising a bottom shield, a top shield, and an element between the bottom shield and the top shield, the element comprising an antiferromagnetic (AFM) layer, a nonmagnetic insertion layer, a pinned layer, a nonmagnetic layer, and a free layer, the nonmagnetic insertion layer having a location within the pinning layer.
  • 28. A method for providing a magnetic apparatus comprising: providing an element, wherein providing the element further comprises: providing a pinning layer;providing a nonmagnetic insertion layer within the pinning layer; andproviding a pinned layer on the pinning layer.
US Referenced Citations (628)
Number Name Date Kind
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
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
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
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
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
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
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
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 al. 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
7266012 Saito et al. 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
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
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
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
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
7564658 Zhang et al. Jul 2009 B2
7583466 Kermiche et al. Sep 2009 B2
7583481 Zhang 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
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
7973349 Huai et al. Jul 2011 B2
7978439 Zhang et al. Jul 2011 B2
7982989 Shi et al. Jul 2011 B1
8008912 Shang Aug 2011 B1
8012316 Zhang et al. Sep 2011 B2
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
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
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
8339754 Zhang et al. Dec 2012 B2
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
8379351 Fuji Feb 2013 B2
8381391 Park et al. Feb 2013 B2
8385027 Zhao 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
8570691 Sato Oct 2013 B2
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
8675316 Lee Mar 2014 B2
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
8755152 Park 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
9121886 Singleton Sep 2015 B2
20020131215 Beach Sep 2002 A1
20030168673 Yuasa Sep 2003 A1
20060061915 Zhang Mar 2006 A1
20070076331 Pinarbasi Apr 2007 A1
20080316657 Zhang Dec 2008 A1
20090168270 Takahashi Jul 2009 A1
20090213503 Sun Aug 2009 A1
20090257152 Lee Oct 2009 A1
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
20120257298 Sato 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
20140154529 Yang et al. Jun 2014 A1
20140175050 Zhang et al. Jun 2014 A1
20140334032 Nishioka Nov 2014 A1
20150332714 Singleton Nov 2015 A1
20160197146 Augusto Jul 2016 A1