Patent Publication Number: US-2011075299-A1

Title: Magnetic write heads for hard disk drives and method of forming same

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     Embodiments of the present invention generally relate to write heads for hard disk drives and in particular to magnetic shields of write heads used for perpendicular recording on a magnetic disk. 
     2. Description of the Related Art 
     There has been increasing progress in the field of magnetic disk storage system technology in recent years. Such success has made storage systems an important component of modern computers. Some of the most important customer attributes of any storage system are the cost per megabyte, data rate, and access time. In order to obtain the relatively low cost of magnetic disk storage systems compared to solid state memory, the customer must accept the less desirable features of this technology, which include a relatively slow response, high power consumption, noise, and the poorer reliability attributes associated with any mechanical system. On the other hand, magnetic storage systems have always been nonvolatile; i.e., no power is required to preserve the data, an attribute which in semiconductor devices often requires compromises in processing complexity, power-supply requirements, writing data rate, or cost. Improvements in areal density (the amount of information that can be placed within a given area on a disk drive), have been the chief driving force behind the historic improvement in storage cost. In fact, the areal density of magnetic disk storage systems continues to increase. As the magnetic particles that make up recorded data on a magnetic disk become ever smaller, technical difficulties in writing and reading such small bits occur. 
     Perpendicular recording is one alternative to increase areal densities when compared with longitudinal recording. In recent years, the increased demand for higher data rate and areal density has driven the perpendicular head design to scale toward smaller dimensions and the need for constant exploration of new head designs, materials, and practical fabrication methods. Some of the problems encountered with perpendicular recording are side writing and side erasure, to adjacent tracks on the disk. These problems occur from leakage and fringing of the magnetic flux from the magnetic write head. To minimize these effects, one approach is to provide either a trailing or wrap-around shield on the magnetic write head. These shields allow effective magnetic flux to be provided for writing to the disk, while avoiding leakage and fringing that can lead to the above-described problems. As the areal density of the disks increases, however, the ability of existing shields to achieve the desired results decreases. 
     SUMMARY OF THE INVENTION 
     The present invention, in a first embodiment, is a magnetic write head for a hard disk drive. A magnetic write head for a hard disk drive. The magnetic head includes an air bearing surface (ABS), a magnetic write pole having an end that defines part of the ABS, the magnetic write pole including a trailing step, such that the write pole has a first thickness at the end that defines part of the ABS and a second thickness in the region of the trailing step, the second thickness being greater than the first thickness and a layer of non-magnetic gap material disposed on the magnetic write pole, the layer of non-magnetic gap material including a taper defined by an increasing thickness of the layer of non-magnetic gap material from a third thickness at a first distance from the ABS, to a fourth thickness at a second distance from the ABS, the second distance being greater than the first distance and the fourth thickness being greater than the third thickness and a magnetic shield disposed on the layer of non-magnetic gap material. 
     In a further embodiment, the invention is a hard disk drive having a magnetic storage disk and a magnetic write head for writing data to the disc drive. The magnetic write head includes an air bearing surface (ABS), a magnetic write pole having an end that defines part of the ABS, the magnetic write pole including a trailing step, such that the write pole has a first thickness at the end that defines part of the ABS and a second thickness in the region of the trailing step, the second thickness being greater than the first thickness and a layer of non-magnetic gap material disposed on the magnetic write pole, the layer of non-magnetic gap material including a taper defined by an increasing thickness of the layer of non-magnetic gap material from a third thickness at a first distance from the ABS, to a fourth thickness at a second distance from the ABS, the second distance being greater than the first distance and the fourth thickness being greater than the third thickness and a magnetic shield disposed on the layer of non-magnetic gap material. 
     In another embodiment the invention is a method of forming a magnetic write head. The method includes providing a substrate, the substrate having a first layer of magnetic material for forming a magnetic pole of the write head, and having a surface, depositing and patterning a resist layer on the surface of the substrate, such that a first part of the surface is covered by the resist layer and a second part of the surface is exposed, depositing a second layer of magnetic material on the exposed part of the surface of the first layer, depositing a third layer of non-magnetic material on the second layer of magnetic material, removing the resist layer, depositing a fourth endpoint layer of on the third layer and on an exposed portion of the first layer, depositing a fifth non-magnetic layer on the fourth layer, selectively removing part of the fifth layer to form a taper in the fifth layer, such that the fifth layer increases in thickness from a first thickness at a first distance from the ABS, to a second thickness at a second distance from the ABS, where the second thickness is greater than the first thickness and the second distance is greater than the first distance, depositing a sixth layer of non-magnetic material on a remainder of the fifth layer and depositing a seventh layer of magnetic material on the sixth layer to form a magnetic shield of the write head. 
     In yet a further embodiment, the invention is another method of forming a magnetic write head. The method includes providing a magnetic write pole having an end that defines part of an ABS, forming a trailing step on the write pole to produce a stepped write pole, such that the stepped write pole has a first thickness at the end that defines part of the ABS and a second thickness in the region of the trailing step, the second thickness being greater than the first thickness, forming a layer of non-magnetic gap material on the stepped write pole, the layer of non-magnetic gap material including a taper defined by an increasing thickness of the layer of non-magnetic gap material from a third thickness at a first distance from the ABS, to a fourth thickness at a second distance from the ABS, the second distance being greater than the first distance and the fourth thickness being greater than the third thickness and forming a magnetic shield on the layer of non-magnetic gap material. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       So that the manner in which the above recited features of the present invention can be understood in detail, a more particular description of the invention, briefly summarized above, may be had by reference to embodiments, some of which are illustrated in the appended drawings. It is to be noted, however, that the appended drawings illustrate only typical embodiments of this invention and are therefore not to be considered limiting of its scope, for the invention may admit to other equally effective embodiments. 
         FIG. 1  shows an exemplary disk drive having a magnetic disk, and magnetic read/write head mounted on an actuator, according to one embodiment of the invention. 
         FIG. 2A  is a side view of the read/write head and magnetic disk of the disk drive of  FIG. 1 , according to one embodiment of the invention. 
         FIG. 2B  is an enlarged side view of a portion of the read/write head of  FIG. 2A , according to one embodiment of the invention. 
         FIG. 2C  is a enlarged top view of a portion of the read/write head of  FIG. 2A , according to a further embodiment of the invention. 
         FIGS. 3A-3G  are side views showing various stages of producing a magnetic write head, according to one embodiment of the invention. 
         FIG. 4  is a cross section of the structure of  FIG. 3G  taken through section line  4 - 4 . 
         FIG. 5  is a cross section of the structure of  FIG. 3G  taken through section line  5 - 5 . 
         FIG. 6  is a cross section of the structure of  FIG. 3G  taken through section line  6 - 6 . 
     
    
    
     DETAILED DESCRIPTION 
     In the following, reference is made to embodiments of the invention. However, it should be understood that the invention is not limited to specific described embodiments. Instead, any combination of the following features and elements, whether related to different embodiments or not, is contemplated to implement and practice the invention. Furthermore, although embodiments of the invention may achieve advantages over other possible solutions and/or over the prior art, whether or not a particular advantage is achieved by a given embodiment is not limiting of the invention. Thus, the following aspects, features, embodiments and advantages are merely illustrative and are not considered elements or limitations of the appended claims except where explicitly recited in a claim(s). Likewise, reference to “the invention” shall not be construed as a generalization of any inventive subject matter disclosed herein and shall not be considered to be an element or limitation of the appended claims except where explicitly recited in a claim(s). 
     Embodiments of the present invention are related to magnetic write heads for hard disk drives. More particularly, the invention is related to the write pole and magnetic shield of a magnetic write head. In some cases, embodiments of the present invention may mitigate magnetic flux leakage and fringing and the problems caused thereby, in magnetic write heads for hard disk drives. While embodiments of the invention are particularly suitable for use in magnetic disk hard drives, this use should not be considered limiting as the magnetic write head of the invention could be used to write to any type of magnetic media, particularly (but not exclusively) where magnetic leakage and fringing is an issue. The advent of perpendicular magnetic recording, (PMR), while providing significantly higher storage density than longitudinal recording, has introduced its own set of challenges. One of these challenges is the need to suppress stray fields from the perpendicular write pole, due to the high writing current required in perpendicular recording. One method of suppressing stray magnetic fields, is through the use of magnetic shields at the trailing end of the read/write head. The shield is separated from the write pole by a shield gap formed of non-magnetic material. The shield gap has a portion of reduced thickness adjacent the ABS and forms a shield gap throat. In the region of the shield gap throat the distance between the magnetic shield and the write pole is reduced. The height of the shield gap throat, from the ABS to the point where the gap starts to increase in thickness is known as the throat height. For high area density PMR, the shield throat height must be relatively small. However, the small throat height tends to cause saturation. Embodiments of the present invention provide a tapered non-magnetic bump in front of (closer to the ABS) a trailing step of the write pole. The tapered bump in the gap material provides a relatively small throat height, while avoiding saturation of the shield. 
     Two common types of magnetic shields for perpendicular write head poles are the trailing shield and the wrap-around shield. A trailing shield is predominantly located on the trailing end of the read/write head, while wrap-around shields provide additional shielding by wrapping around the write pole and covering the sides of the write pole as well as the trailing end. The wrap-around shield is the most efficient type of shield for stray field suppression. Both types of shields benefit from the tapered non-magnetic bump in front of the stepped write pole of the invention. 
       FIG. 1  shows one embodiment of a magnetic hard disk drive  10  that includes a housing  12  within which a magnetic disk  14  is fixed to a spindle motor (SPM) by a clamp. The SPM drives the magnetic disk  14  to spin at a certain speed. A head slider  18  accesses a recording area of the magnetic disk  14 . The head slider  18  has a head element section and a slider to which the head element section is fixed. The head slider  18  is provided with a fly-height control which adjusts the flying height of the head above the magnetic disk  14 . An actuator  16  carries the head slider  18 . In  FIG. 1 , the actuator  16  is pivotally held by a pivot shaft, and is pivoted around the pivot shaft by the drive force of a voice coil motor (VCM)  17  as a drive mechanism. The actuator  16  is pivoted in a radial direction of the magnetic disk  14  to move the head slider  18  to a desired position. Due to the viscosity of air between the spinning magnetic disk  14  and the head slider&#39;s air bearing surface (ABS) facing the magnetic disk  14 , a pressure acts on the head slider  18 . The head slider  18  flies low above the magnetic disk  14  as a result of this pressure balancing between the air and the force applied by the actuator  16  toward the magnetic disk  14 . 
       FIG. 2A  is a fragmented, cross-sectional side view through the center of an embodiment of a read/write head  200  mounted on a slider  201  and facing magnetic disk  202 . In one embodiment, the slider  201  is the head slider  18  of  FIG. 1  and magnetic disk  202  is the magnetic disk  14  of  FIG. 1 . In some embodiments, the magnetic disk  202  may be a “dual-layer” medium that includes a perpendicular magnetic data recording layer (RL)  204  on a “soft” or relatively low-coercivity magnetically permeable underlayer (EBL)  206  formed on a disk substrate  208 . The read/write head  200  includes an air bearing surface (ABS), a magnetic write head  210  and a magnetic read head  211 , and is mounted such that its ABS is facing the magnetic disk  202 . In  FIG. 2A , the disk  202  moves past the write head  210  in the direction indicated by the arrow  232 , so the portion of slider  201  that supports the read/write head  200  is often called the slider “trailing” end  203 . 
     In some embodiments, the magnetic read head  211  is a magnetoresistive (MR) read head that includes an MR sensing element  230  located between MR shields S 1  and S 2 . The RL  204  is illustrated with perpendicularly recorded or magnetized regions, with adjacent regions having magnetization directions, as represented by the arrows located in the RL  204 . The magnetic fields of the adjacent magnetized regions are detectable by the MR sensing element  230  as the recorded bits. 
     The write head  210  includes a magnetic circuit made up of a main pole  212 , a flux return pole  214 , and a yoke  216  connecting the main pole  212  and the flux return pole  214 . The write head  210  also includes a thin film coil  218  shown in section embedded in non-magnetic material  219  and wrapped around yoke  216 . A write pole  220  (also referred to herein as “WP  220 ”) is magnetically connected to the main pole  212  and has an end  226  that defines part of the ABS of the magnetic write head  210  facing the outer surface of disk  202 . In some embodiments, write pole  220  is a flared write pole and includes a flare point  222  and a pole tip  224  that includes an end  226  that defines part of the ABS. In flared write pole embodiments, the width of the write pole  220  in a first direction (into and out of the page in  FIG. 2A ), increases from a first width at the flare point  222  to greater widths away from the ABS, as is shown in  FIG. 2C . The flare may extend the entire height of write pole  220  (i.e., from the end  226  of the write pole  220  to the top of the write pole  220 ), or may only extend from the flare point  222 , as shown in  FIG. 2A . In one embodiment the distance between the flare point  222  and the ABS is between about 30 nm and about 150 nm. In some embodiments, the WP  220  includes a trailing step  262  of magnetic material that extends for a length L along the WP  220 . The step  262  may extend from the flare point  222 , to the end of the write pole  220  opposite the ABS, in some embodiments. The length L is between about 1 μm and about 15 μm. In some embodiments, the trailing step  262  of magnetic material increases the magnetic flux to the WP  220 , by providing a greater thickness of the WP  220  in a direction generally parallel to the ABS and perpendicular to the width of the WP  220 . In operation, write current passes through coil  218  and induces a magnetic field (shown by dashed line  228 ) from the WP  220  that passes through the RL  204  (to magnetize the region of the RL  204  beneath the WP  220 ), through the flux return path provided by the EBL  206 , and back to the return pole  214 . 
       FIG. 2A  also illustrates one embodiment of a magnetic shield  250  that is separated from WP  220  by a nonmagnetic gap layer  256 . In some embodiments, the magnetic shield  250  may be a trailing shield wherein substantially all of the shield material is on the trailing end  203 . Alternatively, in some embodiments, the magnetic shield  250  may be a wrap-around shield wherein the shield covers the trailing end  203  and also wraps around the sides of the write pole  220 , as best shown in  FIGS. 4-6 . As  FIG. 2A  is a cross section through the center of the read/write head  200 , it represents both trailing and wrap-around embodiments. 
     Near the ABS, the nonmagnetic gap layer  256  has a reduced thickness and forms a shield gap throat  258 . The throat gap width is generally defined as the distance between the WP  220  and the magnetic shield  250  at the ABS. The shield  250  is formed of magnetically permeable material (such as Ni, Co and Fe alloys) and gap layer  256  is formed of nonmagnetic material (such as Ta, TaO, Ru, Rh, NiCr, SiC or Al 2 O 3 ). A taper  260  in the gap material provides a gradual transition from the gap width at the ABS to a maximum gap width above the taper  260 . This gradual transition in width, forms a tapered bump in the non-magnetic gap that allows for greater magnetic flux density from the write pole  220 , while avoiding saturation of the shield  250 . It should be understood that the taper  260  may extend either more or less than is shown in  FIGS. 2A-2B . The taper may extend upwards to the other end of shield  250  (not shown), such that the maximum gap width is at the end of the shield opposite the ABS. The gap layer thickness increases from a first thickness (the throat gap width) at a first distance from the ABS (the throat gap height) to greater thicknesses in a direction away from the ABS, to a greatest thickness at a second distance (greater than the first distance) from the ABS. At a third distance from the ABS, greater than the second distance, the gap layer thickness is reduced in the region of the magnetic step  262 . 
       FIG. 2B  shows an enlarged side view of section  290  of  FIG. 2A . Taper  260  forms angle θ relative to the ABS of the read/write head  200 . In one embodiment θ is between about 20° and about 70° to the ABS of the read/write head  200 , and forms a substantially fixed slope. The throat gap width is labeled as TW in  FIG. 2B  and is defined as the distance between the WP  220  and the magnetic shield  250  at the ABS. The taper in the gap layer  256 , allows for a reduced TW without excessive fringing of the magnetic field. In one embodiment, the TW is between about 15 nm and 40 nm. The throat height TH is generally defined as the distance between the ABS and the shield height at the front edge  252  of the shield  250 . In some embodiments, the TH is between about 25 nm and 125 nm. Above the TH, the width of the gap  256  increases to a maximum gap width GW along taper  260 . The taper  260  extends for between 50 nm and 150 nm above the TH, depending on the TW, GW and θ. The maximum gap width GW is between 65 nm and 240 nm. The gap width is reduced to GW R , in the area of the trailing step  262 . GW R  is between 65 nm and 140 nm, in some embodiments. The transition between the front edge  252  and taper  260  may be abrupt and form a sharp corner, or may be more gradual. The transition generally has a radius of curvature R 1  as shown in  FIG. 2B . In one embodiment, R 1  is between about 0 nm and about 35 nm. The greater R 1 , the more gradual the transition. R 2  is shown as the radius of curvature between the taper  260  and the region  270  of maximum gap width. In one embodiment, R 2  is between 0 nm and 75 nm. It is contemplated that R 1  and R 2  may or may not be equal values in varying embodiments. By rounding these corners and providing a gradual transition, the possibility of magnetic field fringing and leakage is reduced. 
       FIG. 2C  shows an enlarged top view of the WP  220  of  FIG. 2A , with the shield layer  250  and the gap layer  256  removed to show details of the WP  220 , according to another embodiment of the invention. In the illustrative embodiment, the magnetic step  262  covers part of the WP  220 . The WP  220  includes flared sides  274 , which extend from the flare point  222  away from the ABS, such that the main pole increases from a first thickness T 1  to greater thicknesses in a direction away from the ABS. In some embodiments, the first thickness, T 1  is between 30 nm and 150 nm. The flared sides  274  form an angle α with respect to the non-flared (substantially parallel) sides  272  of the pole tip  224 . In one embodiment α is between about 30° and about 60°. The trailing step— 262  has a front edge in facing relationship to the ABS that may be aligned with the flare point  222  in some embodiments, such that the magnetic step  262  extends from the flare point  222  and overlies the flared portion of the write pole  220 . In this embodiment, the front edge and the flare point  222  are substantially equidistant from the ABS. By “substantially equidistant” it is meant that the front edge and the flare point  222  are the same distance from the ABS within process tolerances. In some embodiments, these two features are defined by two independent lithographic steps and the alignment is limited by the tolerances of both lithographic steps. In one embodiment, the term “substantially equidistant” is considered to mean that the front edge and the flare point  222  are the same distance from the ABS within 45 nm±. In other embodiments, the magnetic step  262  has a front edge  264  that is closer to the ABS than the flare point  222 , such that part of the pole tip  224  is covered by the magnetic step  262 . In further embodiments, the magnetic step  262  has a front edge  266  that is further from the ABS than the flare point  222 , such that part of the flared write pole  220  is not covered by the trailing step  262 . The alignment of the magnetic step front edge and the flare point  222  may be adjusted during deposition of the trailing step  262 , as described below, to maximize write flux while keeping fringing and leakage to a minimum. The distance between the trailing step front edge ( 264  or  266 ) and the flare point  222 , is between 0 nm (when the front edge of the trailing step and the flare point  222  are aligned with one another) and 100 nm. Thus, the distance from the trailing step front edge and the ABS is between about 75 nm and 275 nm. The desired alignment between the magnetic step front edge and the flare point  222  depends on other structural and functional limitations of the write head  210 . The alignment is chosen to maximize the magnetic field produced by the head, while also suppressing stray fields. 
       FIGS. 3A-3G  illustrate one embodiment of a method for forming the magnetic write head of the invention. In  FIG. 3A  a substrate  300  is shown. Substrate  300  may be WP  220  of  FIGS. 2A-2C , or may be a temporary substrate from which the deposited layers are transferred to WP  220 . In some embodiments, the substrate  300  may be a laminated write pole and will be referred to as such for purposes of illustration. A resist layer  302  is deposited and patterned on top of write pole  300 . The resist layer  302  may be formed of photoresist or other suitable materials, such as deep ultraviolet (DUV)248 nm or 193 nm lithography resist. In flared pole embodiments, when forming the resist layer  302 , the edge  301  of the resist layer  302  is aligned relative to the flare point  222  of the write pole  300 . This alignment determines the final alignment of the magnetic step front edge and the flare point  222  as previously described. After depositing and patterning the resist layer  302 , a magnetic step  304  is plated on the exposed portions of the write pole  300 , to form the trailing step of the WP  220 . The magnetic step  304  is plated to a thickness of between about 50 nm and 100 nm thick, and is made of suitable magnetic material such as Ni, Co and Fe alloys. In some embodiments, the magnetic step  304  may be laminated similar to the laminated write pole of the substrate  300 .  FIG. 3B  shows a non-magnetic step material  306  plated on top of the magnetic step  304 . The non-magnetic step  306  is plated, in one embodiment, to a thickness of between about 50 nm and 100 nm, and is formed of non-magnetic material that can be plated such as NiP, Au or Cu. Continuing to  FIG. 3C , the resist layer  302  is removed and an endpoint layer  308  is deposited on top of and on the sides of layers  304  and  306 , and on top of the exposed portion of the write pole  300 . The endpoint layer  308 , in one embodiment is formed of Ta, Ti, NiCr or Ru and is deposited to a thickness of between about 2 nm and 10 nm. In one embodiment the endpoint layer  308  is deposited by sputtering, although other deposition techniques may be used. The endpoint layer  308  provides an indicator to stop the milling process as described below. 
     After the endpoint layer  308  is deposited, a relatively thick (about 50 nm and 200 nm) non-magnetic layer  310  is conformally deposited on top of endpoint layer  308 , as shown in  FIG. 3D . Non-magnetic layer  310  is formed of a non-magnetic material such as Al 2 O 3  or Ru, that may, in one embodiment, be deposited using atomic layer deposition (ALD). Once the non-magnetic layer  310  is deposited, the structure is subjected to an ion beam milling process. The ion beams (shown as arrows  312 ) are directed at an angle β to the write pole  300 , to form the taper  260  described above. In one embodiment, the angle β is between about 20° and about 50°. The ion beam milling process removes part of the endpoint layer  308  and the non-magnetic layer  310 , leaving portions  308 ′ and  310 ′ and forming the angled surface  309  as shown in  FIG. 3E , by shading of the ion beams by the layers  304  and  306 . The term “shading” used in this context refers to the ability of the material of layers  304  and  306  (in particular  306  as the top layer) to block the ion beams from striking and removing the material of non-magnetic layer  310 , in the region adjacent to layers  304  and  306  (to the left of layers  304  and  306 , in  FIG. 3E ), thereby leaving the material in portion  310 ′ that forms the angled surface  309 . The ion beam milling process, in one embodiment, is conducted using Ar ions and detection of the endpoint layer  308  is conducted using secondary ion mass spectroscopy (SIMS). 
     In  FIG. 3F , a non-magnetic plating seed layer  314 , is shown deposited on top of layers  306 , remaining portions  308 ′ and  310 ′, and the exposed portion of write pole  300 . Non-magnetic plating seed layer  314 , in some embodiments, is formed of high adhesion materials such as Ta or Cr, followed by a high conductivity material such as Ru or Rh. In one embodiment, layers  306 ,  308 ′,  310 ′ and  314  form the non-magnetic gap layer  256  of  FIGS. 2A-2B . Magnetic material (such as Ni, Co and Fe alloys) to form the magnetic shield layer  316  is then plated on non-magnetic plating seed layer  314 , to complete the structure as shown in  FIG. 3G . In some embodiments, magnetic shield layer  316  forms the magnetic shield  250  of  FIGS. 2A-2B . 
       FIG. 4  is a cross section of the structure of  FIG. 3G  taken through section line  4 - 4 , (close to the level of the ABS, as shown in  FIGS. 2A ,  2 B and  3 G). In  FIG. 4 , the write pole (layer  300 ) cross section, close to the ABS, is shown. As can be seen in  FIG. 4 , in one embodiment, the write pole  300  is trapezoidal in cross-section. In another embodiment, the write pole  300  is triangular in cross-section. The write pole  300  is surrounded below and on the sides, by non-magnetic material  400 . Material  400  includes material  219  ( FIG. 2A ) below and on the sides of the write pole  300 . Layer  314  ( FIG. 3G ) forms a thin non-magnetic gap layer on top of the write pole  300  and on the top and sides of material  400 . Shield  316  surrounds the write pole structure and is separated from the top of the write pole  300  by a relatively thinner gap formed by the non-magnetic plating seed layer  314 . Note that, in this embodiment, layers  304 ,  306 ,  308 ′ and  310 ′, are not visible as these layers do not extend to section line  4 - 4  in  FIG. 3G . 
       FIG. 5  is a cross section of the structure of  FIG. 3G  taken through section line  5 - 5 . In  FIG. 5  the write pole  300  is separated from the shield  316  by a relatively thicker gap formed of non-magnetic layers  308 ′,  310 ′ and  314  of  FIG. 3G . It should be noted that the cross section of write pole  300  is substantially similar to the cross section of write pole  300  in  FIG. 4 , as both of these cross sections are taken to the left of the flare point  222  as shown in  FIG. 3G . 
       FIG. 6  is a cross section of the structure of  FIG. 3G  taken through section line  6 - 6 . In  FIG. 6  the cross section of write pole  300  is wider than the cross section of the write pole  300  as shown in  FIGS. 4 and 5 , as this cross section is taken to the right of the flare point  222  in  FIG. 3G . Beneath the write pole  300  is the main pole  212 , (see  FIG. 2A ). The main pole  212  is surrounded by non-magnetic material  400 . The magnetic step  304  is disposed on the write pole  300 , on the top and to the sides thereof. The non-magnetic step  306  is disposed on top of and to the sides of the magnetic step  304 . The non-magnetic plating seed layer  314  covers the top and sides of non-magnetic step  306  and non-magnetic material  400 . The magnetic shield  316  is shown above and to the sides of all of the layers, forming a wrap-around shield. The main pole at this cross section includes main pole  212 , write pole  300  and magnetic step  304 . The magnetic step  304  allows additional magnetic flux to be provided to the write pole  300 , while avoiding fringing or leakage near the ABS. The main pole is separated from the shield  316  by the gap formed of the non-magnetic step  306 , by the non-magnetic side gap material  400  and the non-magnetic plating seed layer  314 . 
     While the foregoing is directed to embodiments of the present invention, other and further embodiments of the invention may be devised without departing from the basic scope thereof, and the scope thereof is determined by the claims that follow.