Abstract:
Methods and structures for electroplating shield structures for perpendicular thin film write poles having ultra thin non-magnetic top gaps on the order of a few nanometers are disclosed. Ultra thin, conductive seed layers serve a dual purpose as both plating seed layer and non-magnetic top gap for the write pole. Due to reduced current carrying capacity of ultra thin seed layers, an additional thick seed layer is also employed to aid delivering plating current to regions near the pole.

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     This invention relates to structures and methods for fabricating thin film perpendicular write heads. More specifically, the invention relates to structures and methods for fabricating wrap around and trailing shields using ultra-thin metal gap seed layers. 
     2. Description of the Related Art 
     Perpendicular write heads are currently well known in the art. Variants of such heads, having wrap around shields and trailing shields, have been recently disclosed. See, for example US Patent Application Publications 2005/0259355, 2006/0044682 and 2006/0174474, assigned to Hitachi Global Storage Technologies, Netherlands B.V. 
     During the fabrication of the wrap around shield of the prior art, a film stack containing the magnetic pole material, a non-magnetic gap layer, a CMP stop layer, and a number of image transfer layers are deposited. After the pole width is imaged and the film stack etched by a number of consecutive etch processes, a film stack containing the tapered pole material is created. A conformal non-magnetic layer is then deposited, which will serve as the side shield or wrap around shield gap material. Following deposition of the side gap material, a layer of RI-etch-able (or RIE-able, reactive ion etch-able) material is deposited and the structure planarized by CMP. Following planarization, the RI-etch-able material is removed leaving the tapered pole, main gap and side gap materials. A magnetic material is then deposited over this structure by electroplating to form the wrap around shield. Prior to plating, a conductive seed layer is deposited to provide a starting cathode for the plating process. As the main gap (or top gap) continues to shrink in thickness to dimensions of a few nanometers or less, the main gap layer is eliminated from the starting film stack, being replaced by the metallic, non-magnetic seed layer used to plate the wrap around shield. Difficulties arise when trying to plate on these ultra-thin seed layers due to their higher resistivity if plating dimensions exceed a few hundred microns. In structures of the prior art, the plating of all shield structures on a wafer is done from a single blanket seed layer. This is no longer possible for seed layers having a thickness of one to two nanometers and below. 
     During the formation of trailing shields of the prior art, a film stack containing the magnetic pole material, a non-magnetic gap layer, a CMP stop layer, and a number of image transfer layers are deposited. The pole width is imaged and the film stack etched by a number of consecutive etch processes, creating a film stack containing the tapered pole material. A filler layer is deposited and the resulting structure planarized by CMP to the stop layer. A plating seed layer is subsequently deposited, followed by deposition of the trailing shield. As with wrap around shields, thinner gap layers require substitution of the pre-deposited gap layer in the film stack with the ultra-thin non-magnetic seed layer. Plating of the trailing shields will experience the same difficulties described above for the wrap around shields. 
     What is needed is a better process for producing the wrap around and trailing shields for the perpendicular write head. 
     SUMMARY OF THE INVENTION 
     It is an object of the present invention to provide a method for making a perpendicular head including fabricating a write pole structure on a first portion of a surface, the write pole structure containing a write pole layer, fabricating a thick seed layer on a second portion of the surface, the thick seed layer having a boundary residing adjacent to the write pole structure, the boundary of the thick seed layer separated from the write pole structure by a distance T. The process further includes depositing an ultra-thin seed layer on the write pole layer, and on at least a portion of the thick seed layer, such that electrical continuity is established between the thick seed layer and the ultra-thin seed layer; and, electroplating a shield structure over the write pole layer by conducting electrical current from the thick seed layer to at least a portion of the ultra-thin seed layer, wherein the ultra-thin seed layer functions as a non-magnetic top gap between the write pole layer and the shield structure, the distance T being greater than the thickness of the thick seed layer, the distance T being less than 15 microns. 
     It is another object of the present invention to provide a method for making a perpendicular head including fabricating a write pole structure on a first portion of a surface, the write pole structure containing a write pole layer, enclosing at least a portion of the write pole structure within a photo-resist layer, subsequent to fabricating the write pole structure, depositing a thick seed layer on the photo resist layer and the second portion of the surface, removing the photo resist layer and a portion of the thick seed layer deposited on the photo resist layer, creating a thick seed layer boundary adjacent to the write pole structure, the boundary of the thick seed layer separated from the write pole structure by a distance T. The process further includes depositing an ultra-thin seed layer on the write pole layer, and on at least a portion of the thick seed layer, such that electrical continuity is established between the thick seed layer and the ultra-thin seed layer; and, electroplating a shield structure over the write pole layer by conducting electrical current from the thick seed layer to at least a portion of the ultra-thin seed layer, wherein the ultra-thin seed layer functions as a non-magnetic top gap between the write pole layer and the shield structure, the distance T being greater than the thickness of the thick seed layer, the distance T being less than 15 microns. 
     It is another object of the present invention to provide a method for making a perpendicular head including fabricating a write pole structure on a first portion of a surface, the write pole structure containing a write pole layer, enclosing at least a portion of the write pole structure within a photo-resist layer, subsequent to fabricating the write pole structure, depositing a thick seed layer on the photo resist layer and the second portion of the surface, the thick seed layer having a thickness between 100 m and 500 nm, removing the photo resist layer and a portion of the thick seed layer deposited on the photo resist layer, creating a thick seed layer boundary adjacent to the write pole structure, the boundary of the thick seed layer separated from the write pole structure by a distance T. The process further includes depositing an ultra-thin seed layer on the write pole layer, and on at least a portion of the thick seed layer, such that electrical continuity is established between the thick seed layer and the ultra-thin seed layer, the ultra-thin seed layer having a thickness between 1 nm and 3 nm; and, electroplating a shield structure over the write pole layer by conducting electrical current from the thick seed layer to at least a portion of the ultra-thin seed layer, wherein the ultra-thin seed layer functions as a non-magnetic top gap between the write pole layer and the shield structure, the distance T being greater than the thickness of the thick seed layer, the distance T being less than 15 microns. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The present invention will be better understood when consideration is given to the following detailed description thereof. Such description makes reference to the annexed drawings, wherein: 
         FIG. 1  is a partial cross section view of the starting film stack, in accordance with embodiments of the present invention; 
         FIG. 2   a  is a partial plan view of the structure of  FIG. 1  subsequent to the imaging and development of photo resist layer  102 , in accordance with embodiments of the present invention; 
         FIG. 2   b  is a partial cross section view through section A-A of  FIG. 2   a , in accordance with embodiments of the present invention; 
         FIG. 3  is a partial cross section view of the structure of  FIGS. 2   a,b  subsequent to the transfer of the image of layer  102 ′ to layers  104  and  106 , in accordance with embodiments of the present invention; 
         FIG. 4  is a partial cross section view subsequent to formation and shaping of pole layer  110 ′, in accordance with embodiments of the present invention; 
         FIG. 5  is a partial cross section view of the structure of  FIG. 4  subsequent to the deposition of side gap layer  502 , in accordance with embodiments of the present invention; 
         FIG. 6  is a partial cross section view of the structure of  FIG. 5  subsequent to ion milling, in accordance with embodiments of the present invention; 
         FIG. 7  is a partial cross section view of the structure of  FIG. 6  subsequent to the formation of photo resist feature  702 , in accordance with an embodiment of the present invention; 
         FIG. 8   a  is a partial plan view of the structure of  FIG. 7 , in accordance with an embodiment of the present invention; 
         FIG. 8   b  is a partial plan view of the structure of  FIG. 7 , in accordance with an alternate embodiment of the present invention; 
         FIG. 8   c  is a partial plan view of the structure of  FIG. 7 , in accordance with an additional alternate embodiment of the present invention; 
         FIG. 9  is a partial cross section view of the structure of  FIG. 7  subsequent to the blanket deposition of thick seed layer  902 , in accordance with an embodiment of the present invention; 
         FIG. 10  is a partial cross section view of the structure of  FIG. 9  subsequent to the lift of photo resist feature  702 , in accordance with an embodiment of the present invention; 
         FIG. 11  is a partial cross section view of the structure of  FIG. 10  subsequent to the deposition of a filler layer, planarization, and removal of the filler layer, in accordance with an embodiment of the present invention; 
         FIG. 12  is a partial cross section view of the structure of  FIG. 11  subsequent to the removal of DLC layer  108 ′, in accordance with an embodiment of the present invention; 
         FIG. 13  is a partial cross section view of the structure of  FIG. 12  subsequent to the deposition of ultra-thin seed layer  1302 , in accordance with an embodiment of the present invention; 
         FIG. 14  is a partial cross section view of the structure of  FIG. 13  subsequent to the electroplating of wrap around shield  1402 , in accordance with an embodiment of the present invention; 
         FIG. 15  is a partial plan view of the structure of  FIG. 14 , in accordance with the embodiment of the present invention shown in  FIG. 8   c;    
         FIG. 16  is a partial plan view of the structure of  FIG. 14 , in accordance with the embodiment of the present invention shown in  FIG. 8   b;    
         FIG. 17  is a partial cross section view of the structure of  FIG. 5  subsequent to ion milling, in accordance with an embodiment of the present invention; 
         FIG. 18  is a partial cross section view of the structure of  FIG. 17  subsequent to the deposition of a filler layer, planarization, and removal of the filler layer, in accordance with an embodiment of the present invention; 
         FIG. 19  is a partial cross section view of the structure of  FIG. 18  subsequent to removal of DLC layer  108 ′, in accordance with an embodiment of the present invention; 
         FIG. 20  is a partial cross section view of the structure of  FIG. 19  subsequent to formation of photo resist feature  702  and deposition of thick seed layer  902 , in accordance with an embodiment of the present invention; 
         FIG. 21  is a partial cross section view of the structure of  FIG. 4  subsequent to the removal of layer  106 ′, in accordance with an embodiment of the present invention; 
         FIG. 22  is a partial cross section view of the structure of  FIG. 21  subsequent to formation of photo resist feature  2202  and deposition of thick seed layer  2204 , in accordance with an embodiment of the present invention; 
         FIG. 23  is a partial cross section view of the structure of  FIG. 22  subsequent to the lift-off of photo resist feature  2202 , in accordance with an embodiment of the present invention; 
         FIG. 24  is a partial cross section view of the structure of  FIG. 23  subsequent to the removal of DLC layer  108 ′ and the deposition of ultra-thin seed layer  2402 , in accordance with an embodiment of the present invention; 
         FIG. 25  is a partial cross section view of the structure of  FIG. 24  subsequent to the electroplating of wrap around shield  2502 , in accordance with an embodiment of the present invention; 
         FIG. 26  is a partial cross section view of the structure of  FIG. 21  subsequent to the removal of DLC layer  108 ′, in accordance with an embodiment of the present invention; 
         FIG. 27  is a partial cross section view of the structure of  FIG. 26  subsequent to formation of photo resist feature  2702  and deposition of thick seed layer  2704 , in accordance with an embodiment of the present invention; 
         FIG. 28  is a partial cross section view of the structure of  FIG. 27  subsequent to the lift-off of photo resist feature  2702 , in accordance with an embodiment of the present invention; 
         FIG. 29  is a partial cross section view of the structure of  FIG. 23  subsequent to the deposition of ultra-thin seed layer  2902 , in accordance with an embodiment of the present invention; 
         FIG. 30  is a partial cross section view of the structure of  FIG. 21  subsequent to the deposition of spacer layer  3002 , in accordance with an embodiment of the present invention; 
         FIG. 31  is a partial cross section view of the structure of  FIG. 30  subsequent to the planarization of spacer layer  3002 , in accordance with an embodiment of the present invention; 
         FIG. 32  is a partial cross section view of the structure of  FIG. 31  subsequent to formation of photo resist feature  3202 , in accordance with an embodiment of the present invention; 
         FIG. 33  is a partial cross section view of the structure of  FIG. 32  subsequent to deposition of thick seed layer  3302 , in accordance with an embodiment of the present invention; 
         FIG. 34  is a partial cross section view of the structure of  FIG. 33  subsequent to the lift-off of photo resist feature  3202 , in accordance with an embodiment of the present invention; 
         FIG. 35  is a partial cross section view of the structure of  FIG. 34  subsequent to the deposition of ultra-thin seed layer  3502 , in accordance with an embodiment of the present invention; 
         FIG. 36  is a partial cross section view of the structure of  FIG. 34  subsequent to the electroplating of trailing shield  3602 , in accordance with an embodiment of the present invention; 
         FIG. 37  is a block diagram of a first process to fabricate a wrap around shield, in accordance with an embodiment of the present invention; 
         FIG. 38  is a block diagram of a second process to fabricate a wrap around shield, in accordance with an embodiment of the present invention; 
         FIG. 39  is a block diagram of a third process to fabricate a wrap around shield, in accordance with an embodiment of the present invention; 
         FIG. 40  is a block diagram of a fourth process to fabricate a wrap around shield, in accordance with an embodiment of the present invention; and, 
         FIG. 41  is a block diagram of a process to fabricate a trailing shield, in accordance with an embodiment of the present invention. 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     The features and description of embodiments the present invention are best understood while viewing the cross sectional structure views ( FIGS. 1-36 ) in light of the process block diagrams ( FIG. 37-41 ).  FIGS. 37 ,  38  disclose first and second processes, respectively, for fabricating a wrap around shield having a side gap thickness greater than the top gap thickness, with the side gap thickness independently adjustable from that of the top gap.  FIG. 38  discloses a process similar to that of  FIG. 37 , except for the re-arrangement of steps to reduce the potential for oxidation of the thick seed layer during the removal of the DLC layers.  FIGS. 39 and 40  disclose third and fourth processes, respectively, for fabricating wrap around shields wherein side and top gaps have the same thickness.  FIG. 40  discloses a process similar to that of  FIG. 39 , except for the re-arrangement of steps to reduce the potential for oxidation of the thick seed layer during the removal of the DLC layers.  FIG. 41  discloses a fifth process for fabricating a trailing shield having an ultra-thin seed layer gap. 
       FIG. 37  is a block diagram  3700  of a first process to fabricate a wrap around shield, in accordance with an embodiment of the present invention. The process begins in step  3702  with a starting thin film layers stack as shown in  FIG. 1 .  FIG. 1  is a partial cross section view of the starting film stack, in accordance with embodiments of the present invention. Layers  102 ,  104 ,  106 ,  108 , and  110  are deposited on base layer  112 , which may be a substrate layer or any other layer compatible with subsequently deposited layers and the electronic function of the completed device. Layer  110  is comprised of magnetic alloys, such as CoFe, CoNiFe, suitable for use in the finished write pole. It may also contain laminates or layers of non-magnetic materials (not shown) as is well known to those skilled in the art. Layer  108  is comprised of DLC (diamond-like carbon), chosen for its suitability as a planarization stop layer. It must be removed completely prior to deposition of the ultra-thin non-magnetic gap layer. There may be cases where this layer can be omitted, where no planarization step is required in the process. These will be noted in discussion below. Layer  106  is comprised of Durimide. Layer  104  is comprised of silica. Layer  102  comprises photo resist and other image transfer components. Details of this layer  102 , well known in the art, are not shown for simplicity. 
     Returning to  FIG. 37 , in step  3704 , the photo resist layer  102  is imaged and developed.  FIG. 2   a  is a partial plan view  200  of the structure of  FIG. 1  subsequent to the imaging and development of photo resist layer  102 , in accordance with embodiments of the present invention.  FIG. 2   b  is a partial cross section view  201  through section A-A of  FIG. 2   a . After imaging and development, photo resist feature  102 ′ defines the shape of the pole to be fabricated. 
     Returning to  FIG. 37 , in step  3706 , feature  102 ′ is transferred to silica layer  104 ′ and Durimide layer  106 ′. Layer  102 ′ is removed. This is accomplished by two different RIE processes. The first transfers the photo resist pattern into the silica layer  104 ; the second transfers the pattern into the underlying Durimide layer  106  (and DLC layer  108 , not shown) using feature  104 ′. The specific etch process conditions are well known to those skilled in the art.  FIG. 3  is a partial cross section view  300  of the structure of  FIGS. 2   a,b  subsequent to the transfer of the image of layer  102 ′ to layers  104  and  106 , in accordance with embodiments of the present invention. Features  106 ′ and  104 ′ are formed. 
     Returning to  FIG. 37 , in step  3708 , the structure of  FIG. 3  is ion milled to form and taper the pole layer  110 ′.  FIG. 4  is a partial cross section view  400  subsequent to formation and shaping of pole layer  110 ′, in accordance with embodiments of the present invention. The width of the pole is shown as W p  ref  402 . 
     Returning to  FIG. 37 , in step  3710 , side gap layer  502  is deposited. Layer  502  is typically alumina, deposited by atomic layer deposition (ALD), as is known to those in the art. In this step, the thickness of the side gap can be partially determined. The total thickness will be equal to the final thickness of layer  502  plus any additional seed layer added to it (see below).  FIG. 5  is a partial cross section view  500  of the structure of  FIG. 4  subsequent to the deposition of side gap layer  502 , in accordance with embodiments of the present invention. 
     Returning to  FIG. 37 , in step  3712 , the structure of  FIG. 5  is ion milled to finalize the side gap thickness and recess layer  112  below the pole layer  110 ′.  FIG. 6  is a partial cross section view  600  of the structure of  FIG. 5  subsequent to ion milling, in accordance with embodiments of the present invention. Conditions and processes for the ion milling are well known to those skilled in the art. 
     Returning to  FIG. 37 , in step  3714 , a blanket photo resist layer is deposited, imaged, and developed, forming photo resist feature  702 .  FIG. 7  is a partial cross section view  700  of the structure of  FIG. 6  subsequent to the formation of photo resist feature  702 , in accordance with an embodiment of the present invention. Photo resist feature  702  is approximately centered over pole layer  110 ′ and extends beyond the width of the pole W p  (ref  402 ) by a dimension T w  (ref  704 ) on both sides. Note that  FIG. 7  is not to scale, and that T w  (ref  704 ) will vary depending on a number of alternate embodiments of the present invention, discussed below in  FIGS. 8   a - c.    
       FIG. 8   a  is a partial plan view  800  of the structure of  FIG. 7 , in accordance with an embodiment of the present invention.  FIG. 7  is a cross section through section B-B of  FIG. 8   a . In this case, photo resist feature  702  spans the entire width of the pole, including the rear pole area beyond the flare point.  FIG. 8   b  is a partial plan view  801  of the structure of  FIG. 7 , in accordance with an alternate embodiment of the present invention.  FIG. 7  again is the cross section through section B-B of  FIG. 8   b . Dimension T w  (ref  704 ) is considerably smaller than it would be in  FIG. 8   a , the purpose of which will be clarified in discussion following.  FIG. 8   c  is a partial plan view  802  of the structure of  FIG. 7 , in accordance with an additional alternate embodiment of the present invention. In this embodiment, photo resist feature  702  is approximately conformal to the outer perimeter of pole layer  110 ′, having a dimension T w  (ref  704 ) considerably smaller than that of  FIG. 8   a.    
     Returning to  FIG. 37 , in step  3716 , a thick seed layer  902  is deposited as a blanket layer over the structure of  FIG. 7 . The purpose of the thick seed layer  902  is to provide a low resistance conduit for electroplating the wrap around shield structure. The thick seed layer  902  may extend to the outer perimeter of the substrate where the electrical plating contacts are made, or alternatively, the thick seed layer may be electrically coupled to an additional conductive bus system on the substrate that makes connection with the power system need to supply electroplating current. Typically, thick seed layer  902  is between about 100 nm and 500 nm thick, preferably between about 250 to 300 nm thick. Thick seed layer  902  can be comprised of any suitable electrical conductor, preferably a metal. Noble metals such at Pd, Au, Rh, Ru, and Pt are suitable, but less desirable due to cost considerations. Noble metals may be more desirable than, for example base metals such as copper or Fe—Co—Ni alloys due to their oxidation resistance. Oxidation resistance may be desirable to minimize damage to the thick seed layer  902  during a subsequent DLC removal step, discussed below. Fe—N—Co alloys may be desirable due to their low cost, good adhesion to photo resist layers, and compatibility with shield electroplating solutions, oxidation resistance not withstanding.  FIG. 9  is a partial cross section view  900  of the structure of  FIG. 7  subsequent to the blanket deposition of thick seed layer  902 , in accordance with an embodiment of the present invention. 
     Returning to  FIG. 37 , in step  3718 , photo resist feature  702  and a portion of thick seed layer  902  is removed in a photo resist lift-off step. The processes and conditions associated with photo resist lift off are well known to those skilled in the art. Subsequent to lift off, the portion of thick seed layer  902  originally deposited on base layer  112  remains, whereas portions of seed layer  902  originally deposited on photo-resist feature  702  are removed with the photo resist. This produces a thick seed layer pattern that is a negative image of the developed photo resist feature  702  disclosed in  FIGS. 8   a - 8   c .  FIG. 10  is a partial cross section view  1000  of the structure of  FIG. 9  subsequent to the lift of photo resist feature  702 , in accordance with an embodiment of the present invention. 
     Returning to  FIG. 37 , in step  3720 , an etchable spacer layer is blanket deposited over the structure of  FIG. 10  (not shown). The resulting structure is then planarized by CMP down to DLC layer  108 ′, removing a portion of the spacer layer and Durimide feature  106 ′ (not shown). The spacer layer is then removed by RIE (not shown). Details of the preceding processes of step  3720  are well known to those in the art.  FIG. 11  is a partial cross section view  1100  of the structure of  FIG. 10  subsequent to the foregoing processes, in accordance with an embodiment of the present invention. 
     Returning to  FIG. 37 , in step  3722 , DLC layer  108 ′ is removed by oxidation.  FIG. 12  is a partial cross section view  1200  of the structure of  FIG. 11  subsequent to the removal of DLC layer  108 ′, in accordance with an embodiment of the present invention. In step  3724  of  FIG. 37 , an ultra thin seed layer  1302  is blanket deposited on the structure of  FIG. 12 . This layer serves multiple purposes. First, it serves as a non-magnetic, ultra thin top gap layer between the top of pole layer  110 ′ and the wrap around shield structure (to be deposited). Secondly, it serves as an electrical conduit to complete the electroplating of the wrap around shield structure conformal to the shape of the pole layer  110 ′ and side gaps  502 . The combination of thick seed layer  902 , terminated in close proximity to the pole, and ultra thin seed layer  1302 , assure proper plating coverage of the wrap around shield. Ultra thin seed layer  1302  is comprised of a non-magnetic metal, preferably a noble metal such Pd, Pt, Rh, and Ru. Typically, the thickness of ultra-thin seed layer  1302  is 2 to 3 nanometers, but thickness below 1 nanometer is possible (and may be required) for future applications. Without thick seed layer  902 , it would not be possible to electroplate a wrap around shield on a blanket seed layer of 1 nanometer in thickness. For ultra thin seed layers  1302  on the order of 1 nanometer, it may be desirable to terminate the thick seed layer  902  as close as possible to the critical areas of the pole. Thus, the embodiments depicted in  FIGS. 8   b  and  8   c  may be more suitable than that of  FIG. 8   a . In accordance with embodiments of the present invention, dimension T w  is less than about 15 microns, preferably less that 10 microns.  FIG. 13  is a partial cross section view  1300  of the structure of  FIG. 12  subsequent to the deposition of ultra-thin seed layer  1302 , in accordance with an embodiment of the present invention. 
     Returning to  FIG. 37 , in step  3726 , the wrap around shield is plated.  FIG. 14  is a partial cross section view  1400  of the structure of  FIG. 13  subsequent to the electroplating of wrap around shield  1402 , in accordance with an embodiment of the present invention. 
       FIG. 15  is a partial plan view  1500  of the structure of  FIG. 14 , in accordance with the embodiment of the present invention shown in  FIG. 8   c . Region  1302 ′ represents the area covered by ultra thin seed layer  1302  over thick seed layer  902 . Region  1302 ″ represents the area covered by ultra thin seed layer  1302  over the pole layer  110 ′, side gap  502 , and a portion of base layer  112  adjacent to the pole.  FIG. 16  is a partial plan view  1600  of the structure of  FIG. 14 , in accordance with the embodiment of the present invention shown in  FIG. 8   b.    
       FIG. 38  is a block diagram  3800  of a second process to fabricate a wrap around shield, in accordance with an embodiment of the present invention. This embodiment differs from that of  FIG. 37  in that the DLC layer  108 ′ is removed before the deposition of the thick seed layer. Since the DLC layer must be removed by an oxidation process, the present embodiment avoids the potential oxidation of the thick seed layer during DLC removal. This is particularly important if the thick seed layer is comprised of base metals like copper, or magnetic alloys such as Fe—Co—Ni. This process shares a number of steps common to that of the first process of  FIG. 37 , namely steps  3702 - 3710 , and  3724 - 3726 . Detailed discussion of these steps shall not be repeated, as they are covered in detail above. The process begins as in step  3720  of  FIG. 37 , and proceeds through step  3710  as discussed above. In step  3802  of  FIG. 38 , side gap  502  and base layer  112  are ion milled in accordance with processes well known in the art.  FIG. 17  is a partial cross section view  1700  of the structure of  FIG. 5  subsequent to ion milling, in accordance with an embodiment of the present invention. In step  3804  of  FIG. 38 , an etchable spacer layer is blanket deposited over the structure of  FIG. 17  (not shown). The resulting structure is then planarized by CMP down to DLC layer  108 ′, removing a portion of the spacer layer and Durimide feature  106 ′ (not shown). The spacer layer is then removed by RIE (not shown). Details of the preceding processes of step  3804  are well known to those in the art.  FIG. 18  is a partial cross section view  1800  of the structure of  FIG. 17  subsequent to the deposition of a filler layer, planarization, and removal of the filler layer, in accordance with an embodiment of the present invention. 
     Returning to  FIG. 38 , in step  3806  DLC layer  108 ′ is removed by oxidation.  FIG. 19  is a partial cross section view  1900  of the structure of  FIG. 18  subsequent to removal of DLC layer  108 ′, in accordance with an embodiment of the present invention. In step  3808  of  FIG. 38 , photo resist feature  702  is produced by deposition, imaging, and development of a blanket photo resist layer. Patterns in accordance with  FIG. 8   a ,  8   b , or  8   c  can be utilized as previously disclosed. In step  3810 , a blanket thick seed layer  902  is deposited. Limitations and compositions of thick seed layer  902  have been previously discussed.  FIG. 20  is a partial cross section view  2000  of the structure of  FIG. 19  subsequent to formation of photo resist feature  702  and deposition of thick seed layer  902 , in accordance with an embodiment of the present invention. 
     Returning to  FIG. 38 , in step  3812 , photo resist feature  702  and a portion of thick seed layer  902  is removed in a lift off process. Subsequent to lift off, the structure of  FIG. 20  becomes that shown in  FIG. 12 . Remaining process steps including the deposition of the ultra thin seed layer and plating of the wrap around shield are the same as steps  3724  and  3726  of  FIG. 37 . 
       FIG. 39  is a block diagram  3900  of a third process to fabricate a wrap around shield, in accordance with an embodiment of the present invention. In this process, the side gap is replaced with ultra thin seed layer, producing a structure having both an ultra thin side gap and top gap. The process shares an number of steps with the first process of  FIG. 37 , namely steps  3702 - 3708 . The process begins at step  3702  of  FIG. 37 , and proceeds through step  3708 , as previously disclosed. In step  3902  of  FIG. 39 , Durimide layer  106 ′ is removed in accordance with processes well known in the art. These processes generally involve a wet chemical soak to remove layer  106 ′. It should be noted that in this particular process, the DLC layer  108  is not required, since there is no planarization step needed to remove layer  106 ′. Alternatively, layer  106 ′ could be removed as was done in the processes disclosed in the planarization processes of  FIGS. 37 and 38 , but this is not preferred due to added complexity and cost. The DLC layer  106  may be present in the initial layer stack of  FIG. 1 , even though it may not be needed in this particular embodiment, to maintain process consistency with other process options.  FIG. 21  is a partial cross section view  2100  of the structure of  FIG. 4  subsequent to the removal of layer  106 ′, in accordance with an embodiment of the present invention. 
     Returning to  FIG. 39 , in step  3904 , photo resist feature  2202  is produced by deposition, imaging, and development of a blanket photo resist layer. Patterns in accordance with  FIG. 8   a ,  8   b , or  8   c  can be utilized as previously disclosed. In step  3906 , a blanket thick seed layer  2204  is deposited. Limitations and compositions of thick seed layer  2204  have been previously discussed.  FIG. 22  is a partial cross section view  2200  of the structure of  FIG. 21  subsequent to formation of photo resist feature  2202  and deposition of thick seed layer  2204 , in accordance with an embodiment of the present invention. In step  3908 , photo resist feature  2202  and a portion of thick seed layer  2204  is removed in a lift off process. DLC layer  108 ′ (if present) is also removed in this step.  FIG. 23  is a partial cross section view  2300  of the structure of  FIG. 22  subsequent to the lift-off of photo resist feature  2202 , and removal of DLC layer  108 ′, in accordance with an embodiment of the present invention. In step  3910 , ultra thin seed layer  2402  is blanket deposited.  FIG. 24  is a partial cross section view  2400  of the structure of  FIG. 23  subsequent to the removal of DLC layer  108 ′ and the deposition of ultra-thin seed layer  2402 , in accordance with an embodiment of the present invention. In step  3912 , wrap around shield  2502  is deposited.  FIG. 25  is a partial cross section view  2500  of the structure of  FIG. 24  subsequent to the electroplating of wrap around shield  2502 , in accordance with an embodiment of the present invention. 
       FIG. 40  is a block diagram  4000  of a fourth process to fabricate a wrap around shield, in accordance with an embodiment of the present invention. This process is a variant of the second process of  FIG. 39 , in that the DLC layer is removed prior to the deposition of the thick seed layer. This is done to reduce potential oxidation of the thick seed layer. The process begins at step  3702  of  FIG. 37 , and proceeds to step  3708  of  FIG. 37 , as previously disclosed. Durimide layer  106 ′ is then removed as in step  3902  of  FIG. 39 . DLC layer  108 ′ is then removed by oxidation in step  4002  of  FIG. 40 .  FIG. 26  is a partial cross section view  2600  of the structure of  FIG. 21  subsequent to the removal of DLC layer  108 ′, in accordance with an embodiment of the present invention. In step  4004  of  FIG. 40 , photo resist feature  2702  is deposited, imaged and developed. Patterns in accordance with  FIG. 8   a ,  8   b , or  8   c  can be utilized as previously disclosed. In step  4006 , a blanket thick seed layer  2704  is deposited. Limitations and compositions of thick seed layer  2704  have been previously discussed.  FIG. 27  is a partial cross section view  2700  of the structure of  FIG. 26  subsequent to formation of photo resist feature  2702  and deposition of thick seed layer  2704 , in accordance with an embodiment of the present invention. In step  4008 , photo resist feature  2702  and a portion of thick seed layer  2704  is removed in a lift off process.  FIG. 28  is a partial cross section view  2800  of the structure of  FIG. 27  subsequent to the lift-off of photo resist feature  2702 , in accordance with an embodiment of the present invention. In step  4010 , ultra thin seed layer  2902  is blanket deposited.  FIG. 29  is a partial cross section view  2900  of the structure of  FIG. 23  subsequent to the deposition of ultra-thin seed layer  2902 , in accordance with an embodiment of the present invention. The wrap around shield is then plated as in step  3912  of  FIG. 39 . 
       FIG. 41  is a block diagram  4100  of a process to fabricate a trailing shield, in accordance with an embodiment of the present invention. The process begins at step  3702  of  FIG. 37 , and proceeds to step  3708  of  FIG. 37 , as previously disclosed. Durimide layer  106 ′ is then removed as in step  3902  of  FIG. 39 . In step  4102  of  FIG. 41 , a spacer layer  3002  is blanket deposited.  FIG. 30  is a partial cross section view  3000  of the structure of  FIG. 21  subsequent to the deposition of spacer layer  3002 , in accordance with an embodiment of the present invention. In step  4104 , the structure is planarized by CMP, utilizing DLC layer  108 ′ as a stop layer.  FIG. 31  is a partial cross section view  3100  of the structure of  FIG. 30  subsequent to the planarization of spacer layer  3002 , in accordance with an embodiment of the present invention. In step  4106 , photo resist feature  3202  is produced by deposition, imaging, and development of a blanket photo resist layer. Patterns in accordance with  FIG. 8   a ,  8   b , or  8   c  can be utilized as previously disclosed.  FIG. 32  is a partial cross section view  3200  of the structure of  FIG. 31  subsequent to formation of photo resist feature  3202 , in accordance with an embodiment of the present invention. Limitations on dimension T t  (ref  3204 ) are similar to those discussed for T w  (ref  704 ) above. In step  4108  of  FIG. 41 , thick seed layer  3302  is deposited. Limitations and compositions of thick seed layer  3302  have been previously discussed.  FIG. 33  is a partial cross section view  3300  of the structure of  FIG. 32  subsequent to deposition of thick seed layer  3302 , in accordance with an embodiment of the present invention. In step  4110 , photo resist feature  3202  and a portion of thick seed layer  3302  is removed in a lift off process.  FIG. 34  is a partial cross section view  3400  of the structure of  FIG. 33  subsequent to the lift-off of photo resist feature  3202 , in accordance with an embodiment of the present invention. In step  4110  of  FIG. 41 , ultra thin seed layer  3502  is blanket deposited.  FIG. 35  is a partial cross section view of the structure of  FIG. 34  subsequent to the deposition of ultra-thin seed layer  3502 , in accordance with an embodiment of the present invention. In step  4112 , trailing shield  3602  is deposited.  FIG. 36  is a partial cross section view  3600  of the structure of  FIG. 34  subsequent to the electroplating of trailing shield  3602 , in accordance with an embodiment of the present invention. 
     The present invention is not limited by the previous embodiments heretofore described. Rather, the scope of the present invention is to be defined by these descriptions taken together with the attached claims and their equivalents.