Magnetic recording writer having a main pole with multiple flare angles

Description

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims priority to provisional U.S. Patent Application Ser. No. 61/807,572, filed on Apr. 2, 2013, which is hereby incorporated by reference in its entirety.

BACKGROUND

FIGS. 1A and 1B depict side and plan views of a conventional magnetic recording head 10. The magnetic recording head 10 may be a perpendicular magnetic recording (PMR) head. The conventional magnetic recording head 10 includes a read transducer 12 and a write transducer 20. The conventional read transducer 12 includes shields 14 and 18 and sensor 16. The read sensor 16 is typically a giant magnetoresistive (GMR) sensor or tunneling magnetoresistive (TMR) sensor. The write transducer 20 includes a first, or return, pole 22, coils 24 and 32, back gap 26, auxiliary poles 28, main pole 30 and shield 344. As can be seen in the plan view, the write pole 30 pole has a flare angle, a. The flare angle is typically on the order of forty-five degrees or less. Although not shown, the main pole 30 may have leading and/or trailing edge bevels. In such cases, the main pole 30 is shortest in the down track direction at the ABS.

Although the conventional magnetic recording head 10 functions, there are drawbacks. In particular, the conventional magnetic recording head 10 may not perform sufficiently at higher recording densities. For example, the write field provided by the main pole 30 and the reverse overwrite may not meet desired standards. Accordingly, what is needed is a system and method for improving the performance of a magnetic recording head.

BRIEF DESCRIPTION OF SEVERAL VIEWS OF THE DRAWINGS

FIGS. 1A-1B depict side and ABS views of a conventional magnetic recording head.

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

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

FIGS. 4A and 4B depict side and plan views of an exemplary embodiment of a magnetic recording transducer.

FIGS. 5A and 5B depict side and plan views of an exemplary embodiment of a magnetic recording transducer.

FIGS. 6A and 6B depict side and plan views of an exemplary embodiment of a magnetic recording transducer.

FIG. 7 is flow chart depicting an exemplary embodiment of a method for fabricating a magnetic recording head.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

FIG. 2 depicts a side view of an exemplary embodiment of a portion 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 102, 110, 120 and 130 are shown. However, multiples of each components 102, 110, 120 and/or and their sub-components, might be used. The disk drive 100 may be a PMR disk drive. However, in other embodiments, the disk drive 100 may be configured for other types of magnetic recording.

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

The transducer 120 is fabricated on the slider 110 and includes an air-bearing surface (ABS) proximate to the media 102 during use. In general, the disk drive 100 includes a write transducer 120 and a read transducer (not shown). However, for clarity, only the write transducer 120 is shown. The transducer 120 includes coil(s) 122 and a main pole 130. In other embodiments, different and/or additional components may be used in the write transducer 120.

As can be seen in FIG. 2, the main pole 130 includes two portions 132 and 134. These portions 132 and 134 are separated by a dotted line because the main pole 130 includes both 132 and 134. The portions 132 and 134 of the main pole are ferromagnetic and may have a high saturation magnetization. For example, the portions 132 and 134 of the main pole may include one or more of CoFe, CoNiFe and NiFe. In other embodiments different and/or additional materials may be used. Further, the portions 132 and 134 may be made of the same or different materials. The portion 132 has a pole tip a portion of which occupies the ABS. The portion 134 is recessed from the ABS. The second portion 134 may be recessed by at least one hundred and not more than three hundred nanometers from the ABS. In some embodiments, the second portion 134 may be recessed on the order of two hundred twenty through two hundred fifty nanometers from the ABS. Although not depicted in FIG. 2, the portions 132 and 134 also have different flare angles. The first portion 132 may be considered to have a first flare angle and a first width in the cross track direction. The second portion 134 has a second flare angle and a second width in the cross track direction. In particular, the second flare angle of the portion 134 is greater than the first flare angle of the portion 132. In some embodiments, the second flare angle is at least seventy degrees. In some such embodiments, the second flare angle is at least seventy-four degrees. In addition, the first portion 132 is wider in the cross track direction than the second portion. Stated differently, the first portion 132 has a maximum width that is greater than that of the second portion. However, in some locations, the widths may be the same. In some embodiments, the maximum width of the second portion 134 is not more than half the maximum width of the first portion 132. Further, although shown as having substantially the same thickness in the down track direction, the second portion 134 may be thinner than the first portion 132. For example, the second portion may be at least fifty and not more than one hundred nanometers thick in the down track direction.

The magnetic disk drive 100 may exhibit improved performance. The main pole 130 having portions 132 and 134 may have a higher write field than a conventional main pole. In addition, the gradient in the write field may be enhanced. Further, the second portion 134 has a smaller width and larger flare angle than the portion 132. As a result, the flux from the main pole 130 may be less likely to leak to any side shields (not shown in FIG. 2). Thus, the increase in write field may be achieved without degrading off track (e.g. wide area track erasure (WATER)) performance. If the disk drive 100 is a PMR disk drive, the on track write field may be enhanced and reverse overwrite (ReOVW) performance improved without sacrificing WATER performance. Further, the main pole 130 may be relatively easily fabricated. If the portions 132 and 134 are made of the same material, a trench deep enough to accommodate the entire pole 130 may be formed and excess material removed so that the second portion 134 has the desired shape. For example, an ion mill may be performed to remove excess magnetic material. In other embodiments, the pole 130 may be fabricated in another manner. Further, the pole 130 may be compatible with different platforms for the disk drive 100. Thus, performance of the disk drive 100 may be improved.

FIGS. 3A and 3B depict side and plan views, respectively, of an exemplary embodiment of a magnetic disk drive 100′. For simplicity, only a portion of the magnetic recording transducer 120′ is shown. For clarity, FIGS. 3A and 3B are not to scale. The magnetic recording disk drive 100′ is analogous to the magnetic disk drive 100. Consequently, analogous components have similar labels. The magnetic recording disk drive 100′ thus includes the write transducer 120′.

The write transducer 120′ includes a main pole 130′, coil(s) 122A and 122B, optional return pole/shield 121, optional shield 125 and optional auxiliary poles 123 and 124. In some embodiments, one or more of the auxiliary poles 123 and 124 may be omitted. The auxiliary pole(s) 123 and 124 are ferromagnetic. The coils 122A and 122B correspond to the coil 122 of FIG. 2. Referring back to FIGS. 3A and 3B, the coils 122A and 122B may be separate pancake coils or may form a single helical coil.

The pole 130′ includes first portion 132′ and second portion 134′. These portions 132′ and 134′ are shown as separated by a dotted line because the main pole 130′ includes both 132′ and 134′. The portions 132′ and 134′ of the main pole 130′ are analogous to the portions 132 and 134 of the main pole 130, respectively. Thus, the portions 132′ and 134′ are ferromagnetic and may have a high saturation magnetization. For example, the portions 132′ and 134′ of the main pole may include one or more of CoFe, CoNiFe and NiFe. Further, the portions 132′ and 134′ may be made of the same or different materials.

The portion 132′ has a pole tip a portion of which occupies the ABS. The pole tip may also include at least part of the bevel 133. The sidewalls of the first portion 132′ form a first flare angle, α1, with the ABS. The first portion also has a first width in the cross track direction. The first flare angle may be less than fifty degrees. In some embodiments, the first flare angle is not more than forty five degrees. The first portion 132′ of the main pole 130′ also includes bevels 131 and 135. In some embodiments, one or both of the bevels 131 and 135 may be omitted.

The second portion 134′ of the main pole 130′ is recessed from the ABS by a distance d. In some embodiments, d is at least one hundred and not more than three hundred nanometers. The second portion 134′ has sidewalls that form a second flare angle, α2, with the ABS. The second portion 134′ also has a second width in the cross track direction. The second flare angle of the portion 134′ is greater than the first flare angle of the portion 132′. In some embodiments, the second flare angle is at least seventy degrees. In some such embodiments, the second flare angle is at least seventy-four degrees. In the embodiment shown, the second portion 134 extends from the distance d from the ABS to the auxiliary pole 124. However, in other embodiments, a space may exist between the second portion 134 of the main pole 130′ and the auxiliary pole 124.

The widths of the portions 132′ and 134′ in the cross track direction generally differ at least in part because of the difference in the flare angles α1 and α2. In the embodiment shown, the width of the portion 132′ is greater than or equal to the width of the second portion 134′ at a distance d from the ABS. In the embodiment shown, the width of the second portion 134′ is not more than half of the width of the first portion 132′ at the distance d from the ABS. Because of the difference in flare angles, at other distances from the ABS, the first portion 132′ is even wider in the cross track direction than the second portion 134′. Further, the thickness in the down track direction of the second portion 134′ may be less than that of the first portion 132′. For example, the second portion 134′ may be at least fifty and not more than one hundred nanometers thick in the down track direction. However, in other embodiments, other widths and/or thicknesses may be used.

The second portion 134′ of the main pole 132′ includes bevel 135. In the embodiment shown, the bevel 135 of the second portion 134′ matches the bevel 133 of the first portion 132′. Stated differently, the bevels 133 and 135 are both at the same angle from the ABS. Thus, the bevels 133 and 135 form a single beveled surface for the main pole 130′. Further, in some embodiments the widths of the portions 132′ and 134′ match at the ABS facing surface. This means that at least at the bottom of the beveled surface 135 and the top of the beveled surface 133, the widths of the portions 132′ and 134′ are the same. However, in other embodiments, the width of the first portion 132′ may be greater than that of the second portion 134′ at all distances from the ABS. In such embodiments, the bevels 133 and 135 form a single, smooth beveled surface for the main pole 130′. Further, in the embodiment shown, the second portion 134′ extends to the ABS facing surface of the auxiliary pole 124. In other embodiments, there may be a space between the second portion 134′ and the auxiliary pole 124.

The magnetic disk drive 100′ may share the benefit(s) of the magnetic disk drive 100. The main pole 130′ having portions 132′ and 134′ may have a higher write field and higher write field gradient than a conventional main pole. Further, the second portion 134′ has a smaller width and larger flare angle than the first portion 132′. As a result, the flux from the main pole 130′ may be increased while substantially maintaining off track performance. Further, the main pole 130′ may be relatively easily fabricated. Further, the pole 130′ may be compatible with different platforms for the disk drive 100′. Thus, performance of the disk drive 100′ may be improved.

FIGS. 4A and 4B depict side and plan views, respectively, of an exemplary embodiment of a magnetic disk drive 100″. For simplicity, only a portion of the magnetic recording transducer 120″ is shown. For clarity, FIGS. 4A and 4B are not to scale. The magnetic recording disk drive 100″ is analogous to the magnetic disk drives 100 and 100′. Consequently, analogous components have similar labels. The magnetic recording disk drive 100″ thus includes the write transducer 120″ having a main pole 130″, coil(s) 122A and 122B, optional return pole/shield 121, optional shield 125 and optional auxiliary poles 123 and 124 that are analogous to the main pole 130′, coil(s) 122A and 122B, optional return pole/shield 121, optional shield 125 and optional auxiliary poles 123 and 124. Thus, the structure and function of the pole 130/130′, coil(s) 122A and 122B, optional return pole/shield 121, optional shield 125 and optional auxiliary poles 123 and 124 are analogous to that of the main pole 130′, coil(s) 122A and 122B, optional return pole/shield 121, optional shield 125 and optional auxiliary poles 123 and 124.

The pole 130″ includes first portion 132″ and second portion 134″ analogous to portions 132/132′ and 134/134′, respectively. Thus, the structure, function and material(s) used for the portions 132″ and 134″ may be analogous to those of portions 132/132′ and 134/134′, respectively. For example, the flare angle α1′ of the portion 132″ and the flare angle α2′ of the portion 134″ are analogous to the flare angles α1 and α2. Consequently, α2′ is greater than α1′ and may be at least seventy four degrees. Further, the width of the second portion 134″ in the cross track direction is less than or equal to that of the first portion 132″. The second portion 134″ is also thin in the down track direction. For example, the second portion 134″ may be at least fifty nanometers and not more than one hundred nanometers thick.

The second portion 134″ of the main pole 130″ includes bevel 135′, while the first portion 132″ of the main pole 130″ includes bevel 133′. In the embodiment shown, the bevel 135′ of the second portion 134′ has a different angle than the bevel 133′ of the first portion 132″. Further, in some embodiments the widths of the portions 132″ and 134″ match at the ABS facing surface. This means that at least at the bottom of the beveled surface 135′ and the top of the beveled surface 133′, the widths of the portions 132″ and 134″ are the same. However, in other embodiments, these widths may differ. Finally, the second portion 132″ starts at the top of the bevel 133′. As a result, the bevels 133′ and 135′ form a single surface having an angle where the surfaces 133′ and 135′ meet. Further, in the embodiment shown, the second portion 134″ extends to the ABS facing surface of the auxiliary pole 124. In other embodiments, there may be a space between the second portion 134″ and the auxiliary pole 124.

The magnetic disk drive 100″ may share the benefit(s) of the magnetic disk drives 100 and/or 100′. The main pole 130″ having portions 132″ and 134″ may have a higher write field and higher write field gradient than a conventional main pole. Further, the second portion 134′ has a smaller width and larger flare angle than the portion 132′. As a result, the flux from the main pole 130″ may be increased while substantially maintaining off track performance. Further, the main pole 130″ may be relatively easily fabricated. Further, the pole 130″ may be compatible with different platforms for the disk drive 100″. Thus, performance of the disk drive 100″ may be improved.

FIGS. 5A and 5B depict side and plan views, respectively, of an exemplary embodiment of a magnetic disk drive 100′″. For simplicity, only a portion of the magnetic recording transducer 120′″ is shown. For clarity, FIGS. 5A and 5B are not to scale. The magnetic recording disk drive 100′″ is analogous to the magnetic disk drives 100, 100′ and 100″. Consequently, analogous components have similar labels. The magnetic recording disk drive 100′″ thus includes the write transducer 120′″ having a main pole 130′″, coil(s) 122A and 122B, optional return pole/shield 121, optional shield 125 and optional auxiliary poles 123 and 124 that are analogous to the main pole 130, 130′ and 130″, coil(s) 122A and 122B, optional return pole/shield 121, optional shield 125 and optional auxiliary poles 123 and 124. Thus, the structure and function of the pole 130′″, coil(s) 122A and 122B, optional return pole/shield 121, optional shield 125 and optional auxiliary poles 123 and 124 are analogous to that of the main pole 130/130′/130″, coil(s) 122A and 122B, optional return pole/shield 121, optional shield 125 and optional auxiliary poles 123 and 124.

The pole 130′″ includes first portion 132′″ and second portion 134′″ analogous to portions 132/132′/132″ and 134/134′/134″, respectively. Thus, the structure, function and material(s) used for the portions 132′″ and 134′″ may be analogous to those of portions 132/132′/132″ and 134/134′/134″, respectively. For example, the flare angle α1″ of the portion 132′″ and the flare angle α2″ of the portion 134′″ are analogous to the flare angles α1/α1′ and α2/α2′. Consequently, α2″ is greater than α1″ and may be at least seventy four degrees. Further, the width of the second portion 134′″ in the cross track direction is less than or equal to that of the first portion 132′″. In some embodiments, the width of the second portions 134′″ is not more than half the width of the first portion 132′″. The second portion 134′″ is also thin in the down track direction. For example, the second portion 134′″ may be at least fifty nanometers and not more than one hundred nanometers thick.

The second portion 134′″ of the main pole 130′″ includes bevel 135″, while the first portion 132′″ of the main pole 130′″ includes bevel 133″. In the embodiment shown, angle of the bevel 135″ of the second portion 134′″ matches the bevel 133″ of the first portion 132′″. In other embodiments, the angles of the bevels 133″ and 135″ may differ. In some embodiments the widths of the portions 132″ and 134″ match at the ABS facing surface. This means that at least at the bottom of the beveled surface 135″ and the top of the beveled surface 133″, the widths of the portions 132′″ and 134′″ may be the same. In other embodiments, these widths may differ. However, in the embodiment shown, the distance, d, that the second portion 134′″ is recessed is greater than the amount that the top edge of the bevel 133″ is recessed. Consequently, there is a space between the bevel 133″ and the bevel 135″. Further, in the embodiment shown, the second portion 134′″ extends to the ABS facing surface of the auxiliary pole 124. In other embodiments, there may be a space between the second portion 134′″ and the auxiliary pole 124.

The magnetic disk drive 100′″ may share the benefit(s) of the magnetic disk drives 100, 100′, and/or 100″. The main pole 130′″ having portions 132′″ and 134′″ may have a higher write field and larger write field gradient than a conventional main pole. Further, the second portion 134′″ has a smaller width and larger flare angle than the portion 132′″. As a result, the flux from the main pole 130′″ may be increased while substantially maintaining off track performance. Further, the main pole 130′″ may be relatively easily fabricated. Further, the pole 130′″ may be compatible with different platforms for the disk drive 100′″. Thus, performance of the disk drive 100′″ may be improved.

FIGS. 6A and 6B depict side and plan views, respectively, of an exemplary embodiment of a magnetic disk drive 100″″. For simplicity, only a portion of the magnetic recording transducer 120″″ is shown. For clarity, FIGS. 6A and 6B are not to scale. The magnetic recording disk drive 100″″ is analogous to the magnetic disk drives 100, 100′, 100″ and 100′″. Consequently, analogous components have similar labels. The magnetic recording disk drive 100″″ thus includes the write transducer 120″″ having a main pole 130″″, coil(s) 122A and 122B, optional return pole/shield 121, optional shield 125 and optional auxiliary poles 123 and 124 that are analogous to the main pole 130, 130′, 130″ and 130′″, coil(s) 122A and 122B, optional return pole/shield 121, optional shield 125 and optional auxiliary poles 123 and 124. Thus, the structure and function of the pole 130″″, coil(s) 122A and 122B, optional return pole/shield 121, optional shield 125 and optional auxiliary poles 123 and 124 are analogous to that of the main pole 130/130′/130″, coil(s) 122A and 122B, optional return pole/shield 121, optional shield 125 and optional auxiliary poles 123 and 124.

The pole 130″″ includes first portion 132″″ and second portion 134″″ analogous to portions 132/132′/132″/132′″ and 134/134′/134″/134′″, respectively. Thus, the structure, function and material(s) used for the portions 132″″ and 134″″ may be analogous to those of portions 132/132′/132″/132′″ and 134/134′/134″/134′″, respectively. For example, the flare angle α1′″ of the portion 132″″ and the flare angle α2′″ of the portion 134″″ are analogous to the flare angles α1/α1′/α1″ and α2/α2′/α2″. Consequently, α2′″ is greater than α1′″ and may be at least seventy four degrees. Further, the width of the second portion 134′″ in the cross track direction is less than or equal to that of the first portion 132″″. In some embodiments, the width of the second portion 134′″ is not more than half that of the first portion 132′″. The second portion 134″″ is also thin in the down track direction. For example, the second portion 134″″ may be at least fifty nanometers and not more than one hundred nanometers thick.

The second portion 134″″ of the main pole 130″″ includes bevel 135′″, while the first portion 132″″ of the main pole 130″″ includes bevel 133′″. In the embodiment shown, angle of the bevel 135′″ of the second portion 134″″ forms a different angle with the ABS than the bevel 133′″ of the first portion 132″. In other embodiments, the angles of the bevels 133″ and 135″ may have the same angle with the ABS. In the embodiment shown, the second portion 132″″ is recessed further from the ABS than the top edge of the bevel 133′″. However, in other embodiments, the bottom edge of the bevel 135′″ may be at the same location as the top edge of the bevel 133′″. Further, in the embodiment shown, the second portion 134″″ does not extend to the ABS facing surface of the auxiliary pole 124. Thus, there is a space between the second portion 134″″ and the auxiliary pole 124. In other embodiments, the second portion 134″″ may adjoin the auxiliary pole 124. In some embodiments the widths of the portions 132″″ and 134″″ match at the ABS facing surface. This means that at least at the bottom of the beveled surface 135′″ and the top of the beveled surface 133′″, the widths of the portions 132′″″ and 134″″ may differ. However, in the embodiment shown, the distance, d, that the second portion 134″″ is recessed is greater than the amount that the top edge of the bevel 133″″ is recessed.

The magnetic disk drive 100″″ may share the benefit(s) of the magnetic disk drives 100, 100′, 100″ and/or 100′″. The main pole 130″″ having portions 132″″ and 134″″ may have a higher write field and larger write field gradient than a conventional main pole. Further, the second portion 134″″ has a smaller width and larger flare angle than the portion 132″″. As a result, the flux from the main pole 130″″ may be enhanced while substantially maintaining off track performance. Further, the main pole 130″″ may be relatively easily fabricated. Further, the pole 130″″ may be compatible with different platforms for the disk drive 100″″. Thus, performance of the disk drive 100″″ may be improved. Further although various features are described in FIGS. 2, 3A-3B, 4A-4B, 4A-5B and 6A-6B, one or more of the features may be combined in manners not shown.

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

Referring to FIGS. 3A, 3B and 7, the coil(s) 122A and/or 122B are provided, via step 202. Portions of step 202 may thus be interleaved with the remaining steps of the method 200. For example, the coil 122A may be provided before the formation of the auxiliary poles 123 and 124 and the main pole 130′. However, the coil 122B may be provided after these structures 123, 124 and 130′ have been formed. Step 202 may also include depositing and patterning the material(s) used for the coil(s) 122A and/or 122B. Step 202 may include forming a single helical coil formed of the coils 122A and 122B. Alternatively, one or two pancake coils may be formed using coils 122A and/or 122B. In such embodiments, a pancake coil 122A and/or 122B may include other turns far from the ABS (not shown in FIGS. 3A-3B).

The auxiliary pole(s) 123 and 124 may optionally be provided, via step 204. Portions of step 204 may thus be interleaved with other steps. For example, the auxiliary pole 123 may be provided before the main pole 130′. However, the auxiliary pole 124 may be provided after the main pole 130′. In other embodiments, some or all of step 204 may be omitted. For example, the auxiliary pole 123 may be omitted, the auxiliary pole 124 may be omitted or both auxiliary poles 123 and 124 may be omitted.

The main pole 130′ is provided, via step 206. Step 206 may include using a damascene process. For example, a trench may be formed in a layer and the material(s) for the pole 130′ deposited and patterned. In some embodiments, the trench formed is deep enough to accommodate both portions 132′ and 134′. One or more ferromagnetic materials are deposited. Part of the material(s) at the top of the pole 130′ may be removed, for example via ion milling. Thus, the first portion 132′ and the second portion 134′ may be formed. In other embodiments, different material(s) may be used for the first and second portions of the main pole 130′. In such embodiments, the material(s) for the first portion 132′ may be deposited, then the material(s) for the second portion 134′ deposited. In such embodiments, the first portion 132′ may be masked before deposition of the second portion. In other embodiments, the second portion 134′ may be masked and milled after deposition. Other methods may also be used to form the pole 130′ including but not limited to full film deposition of magnetic materials and removal for example via milling and/or lapping. The shield(s) 125 may also optionally be provided, via step 208.

Using the method 200, the magnetic disk drives 100, 100′, 100″, 100′″ and/or 100″″ may be provided. Thus, the benefits of the magnetic disk drive(s) 100, 100′, 100″, 100′″, and/or 100″″ may be achieved.