Abstract:
Provided herein is a method including oxidizing tops of features of a patterned magnetic layer to form oxidized tops of the features; removing an excess of an applied first protective material down to at least the oxidized tops of the features to form a planarized layer; and applying a second protective material over the planarized layer.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application claims the benefit of U.S. Provisional Patent Application No. 61/844,428, filed Jul. 10, 2013, which is incorporated herein in its entirety. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
       FIG. 1  shows a block diagram of an overview of a method of BPM fabrication using a filler protective layer process of one embodiment. 
       FIG. 2  shows a block diagram of an overview flow chart of a method of BPM fabrication using a filler protective layer process of one embodiment. 
       FIG. 3  shows a block diagram of an overview flow chart of using the filler as the protective layer of one embodiment. 
       FIG. 4  shows a block diagram of an overview flow chart of depositing an overlying, high anisotropy, continuous magnetic layer of one embodiment. 
       FIG. 5  shows a block diagram of an overview flow chart of BPM magnetic quality of one embodiment. 
       FIG. 6  shows for illustrative purposes only an example of an oxidized surface of BPM patterned features of one embodiment. 
       FIG. 7  shows for illustrative purposes only an example of removing excess sacrificial layer of one embodiment. 
       FIG. 8  shows for illustrative purposes only an example of removing oxide layer from the top of bits of one embodiment. 
       FIG. 9  shows for illustrative purposes only an example of cross-linking bake process of one embodiment. 
       FIG. 10  shows for illustrative purposes only an example of depositing overlying, high anisotropy, continuous magnetic layer(s) of one embodiment. 
       FIG. 11A  shows for illustrative purposes only an example of reminiscent magnetization in polar and transverse directions for an overlying, high anisotropy, continuous magnetic layer of one embodiment. 
       FIG. 11B  shows for illustrative purposes only an example schematic of recording process of one embodiment. 
    
    
     DETAILED DESCRIPTION 
     In a following description, reference is made to the accompanying drawings, which form a part hereof, and in which is shown by way of illustration a specific example in which the embodiments may be practiced. It is to be understood that other embodiments may be utilized and structural changes may be made without departing from the scope. 
     General Overview 
     It should be noted that the descriptions that follow, for example, in terms of a method of BPM fabrication using a filler protective layer process is described for illustrative purposes and the underlying system can apply to any number and multiple types of magnetic recording patterns. In one embodiment, a method of BPM fabrication using a filler protective layer process can be configured using a cross-linked filler layer as a protective layer for etching BPM magnetic features. The method of BPM fabrication using a filler protective layer process can be configured to include an etched oxidized feature layer and can be configured to include an non-etched oxidized feature layer and an overlying, high anisotropy, continuous magnetic layer coupled granular/continuous layer (CGC) using the embodiments. 
       FIG. 1  shows a block diagram of an overview of a method of BPM fabrication using a filler protective layer process of one embodiment.  FIG. 1  shows a method of BPM fabrication using a filler protective layer process  100 . The method of BPM fabrication using a filler protective layer process  100  is a process for using the filler as the protective layer for sidewalls of individual patterned BPM features during the oxide removal from the individual patterned BPM features surface  110 . The method of BPM fabrication using a filler protective layer process  100  enables excluding an oxide layer removal step  120  that can damage BPM features and magnetic materials thereof, including a reducing of the patterned volume. 
     The method of BPM fabrication using a filler protective layer process  100  includes an alternative process used for forming an overlying, high anisotropy, continuous magnetic layer, which improves media performance by adding effective magnetic volume to individual bits while making the surface completely flat  130 . Improved surface topography improves fly-ability with reduced head-to-media spacing (HMS)  140 . The method of BPM fabrication using a filler protective layer process  100  prevents damage to the BPM features and results in amplifying reminiscent magnetization of the BPM features in a BPM stack  150  of one embodiment. 
     DETAILED DESCRIPTION 
       FIG. 2  shows a block diagram of an overview flow chart of a method of BPM fabrication using a filler protective layer process of one embodiment.  FIG. 2  shows the method of BPM fabrication using a filler protective layer process  100 , which includes the following steps: A seed layer is deposited on a soft underlayer (SUL) deposited on a substrate  200 . A deposition of a carbon (C) mask on a magnetic layer deposited on the seed layer  210  is used in patterning processes. A process is used to mill the magnetic layer structure through the C mask to guide the BPM pattern transfer  220  including use of an etch process  230  selected from an ion beam etch (IBE), a focused ion beam (FIB) etch, a reactive ion beam etching (RIBE) process, and a chemically assisted ion beam etch (CAIBE) processes. An etch process is used to remove residual C mask while oxidizing the BPM patterned magnetic media surface creating an oxide layer  240 . An alternative processing path is described in  FIG. 4  of one embodiment. 
     The processing continues along this path and includes a process to spin a sacrificial filler overcoating layer using resist, polymer, hydrogen silsesquioxane (HSQ), or liquid C, and/or other materials  250 . The sacrificial filler is used to protect the patterned BPM features during subsequent processing, to add robustness to the patterned bits, and to prevent bits dislocation and deforming. A process using a bake process including a heat and/or an ultra-violet (UV) process may be used to harden the sacrificial filler overcoating layer  260 . The process may use the bake process to cross-link the sacrificial filler overcoating layer to physically strengthen the BPM features  270 . Processing is further described in  FIG. 3  of one embodiment. 
       FIG. 3  shows a block diagram of an overview flow chart of using the filler as the protective layer of one embodiment.  FIG. 3  shows continuing from  FIG. 2  processing using the filler as the protective layer for sidewalls of individual patterned BPM features during the oxide removal from the individual patterned BPM features surface  110 . A process is also used to remove excess sacrificial layer by etching it back using the oxide layer as a stop layer at the top portion of the BPM features  300 . The BPM features are protected from damage by the sacrificial layer of one embodiment. 
     A process to remove oxide layer from the top of bits may include using a chemical etch, mill, or CMP using a sacrificial layer for protection  310 . The removal processes includes using a planarization process including chemical mechanical polishing (CMP), chemical etching, or mill processing  320 . A deposition process is used to deposit an overcoat (COC) and is followed with lube, burnishing, and buffing processes  330 . An armoring structure  340  (by resist baking, e-beam hardening, or UV hardening) is created to protect the BPM features during processing and results in a planar surface topography, product robustness, and improved fly-ability  350  with reduced head-to-media spacing (HMS)  140 . The method of BPM fabrication using a filler protective layer process  100  is used for amplifying reminiscent magnetization of BPM features in a BPM stack  150  of one embodiment. 
       FIG. 4  shows a block diagram of an overview flow chart of depositing an overlying, high anisotropy, continuous magnetic layer of one embodiment.  FIG. 4  shows the alternative processing path continuing from  FIG. 2 . A process is used to spin sacrificial filler overcoating layer using resist materials  400 . A bake process including a heat and/or an ultra-violet (UV) process may be used to harden the sacrificial filler overcoating layer  260 . The bake process cross-links the sacrificial filler overcoating layer to physically strengthen the BPM features  270 . Hardening and cross-linking enables using the filler as the protective layer for protection of sidewalls of individual patterned BPM features during the oxide removal from the individual patterned BPM features surface  110  of one embodiment. 
     A process is used to remove excess of sacrificial layer by etching it back using the oxide layer for a stop layer at the top portion of the BPM features  300 . A deposition process is used to deposit an overlying, high anisotropy, continuous magnetic layer with special magnetic properties including low reminiscence in a polar direction (perpendicular to magnetic layer) and no hysteresis in a transverse direction (parallel to magnetic layer) over the tops of the bits  410 . The deposition of the overlying, high anisotropy, continuous magnetic layer modifies a top surface of the individual patterned features and reduces head-to-media spacing while amplifying reminiscent magnetization of the patterned features of the stack. Varying this layer geometry and composition may enhance the magnetic characteristics by increasing an effective volume of magnetic material in individual bits  420  and can be done during the deposition process. Continuing descriptions of the process are shown in  FIG. 5  of one embodiment. 
       FIG. 5  shows a block diagram of an overview flow chart of BPM magnetic quality of one embodiment.  FIG. 5  shows continuing from  FIG. 4  the process to deposit an overcoat (COC) and is followed with lube, burnishing, and buffing processes  330 . The filler protective layer is used to maintain the volume of the patterned BPM features and prevent damage of the magnetic materials, which results in amplified BPM magnetic quality including coercivity (Hc), perpendicular anisotropy energy (Ku), Switching Field Distribution (SFD), and others  500 . The method of BPM fabrication using a filler protective layer process  100  of  FIG. 1  produces improved manufacturability by eliminating an oxide layer cleaning process  510 ; improved surface topography; improved surface morphology by adding a top magnetic alloy layer  520 ; product robustness; and improved fly-ability  350  of one embodiment. 
       FIG. 6  shows for illustrative purposes only an example of an oxidized surface of BPM patterned feature of one embodiment.  FIG. 6  shows a process to mill a magnetic layer structure through C mask to guide the BPM pattern transfer  220 . The mill can include an ion beam etch (IBE) etching of a BPM magnetic recording pattern  650 . The BPM pattern transfer is made through the carbon (C) mask layer  640  and into the magnetic layer  630  deposited onto a seed layer  620 . The magnetic layer  630  is a magnetic layer using materials that may include cobalt-chromium-platinum (CoCrPt)  635 . The seed layer  620  is deposited on a soft underlayer (SUL)  610  deposited on a substrate  600 . The BPM pattern transfer creates BPM features with residual C mask material on top of one embodiment. 
     A process may be used including an oxygen (O 2 ) strip process  680  to remove residual C mask while oxidizing the BPM patterned magnetic media surface creating an oxide layer  240 . The oxygen (O 2 ) strip process  680  removes the etched mask  670  residue and oxidizes the surfaces of etched magnetic BPM features  660  including those previously protected by the mask. An oxidized surface of patterned magnetic material  690  covers the etched magnetic BPM features  660 . The processing continues in two configurations, the first is described in  FIG. 7 , and an alternative processing path is described in  FIG. 9  of one embodiment. 
       FIG. 7  shows for illustrative purposes only an example of removing excess sacrificial layer of one embodiment.  FIG. 7  shows continuing from  FIG. 6  the spin sacrificial filler overcoating layer using resist, polymer, hydrogen silsesquioxane (HSQ), or liquid C, and/or other materials  250 , such as an HSQ sacrificial filler  700  layer. The HSQ sacrificial filler  700  covers the oxidized surface of patterned magnetic material  690  and exposed sections of the seed layer  620  surface. The HSQ sacrificial filler  700  may also cover the etched magnetic BPM features  660 , substrate  600 , and soft underlayer (SUL)  610  of one embodiment. 
     A bake process including heat and/or ultra-violet (UV) processes may be used to harden the sacrificial filler overcoating layer  260 . A cross-linking bake process using heat  710  cross-links the HSQ sacrificial filler  700  with the oxidized surface of patterned magnetic material  690  and etched magnetic BPM features  660 . The cross-linking protects the oxidized surface of patterned magnetic material  690  and etched magnetic BPM features  660  during subsequent processing. The bake process does not affect the substrate  600 , soft underlayer (SUL)  610 , and seed layer  620  of one embodiment. 
     The processing continues using a planarization process to remove excess sacrificial layer to the top of the BPM features oxidized surface  720 . The oxidized surface of patterned magnetic material  690  and etched magnetic BPM features  660  are protected from damage or deterioration during the planarization process by the HSQ sacrificial filler  700 . The processing continues and is described in  FIG. 8  of one embodiment. 
       FIG. 8  shows for illustrative purposes only an example of removing oxide layer from the top of bits of one embodiment.  FIG. 8  shows continuing from  FIG. 7  a process to remove oxide layer from the top of bits using a chemical etch, mill, or CMP using a sacrificial layer for protection  310 . An etch planarization process  800  removes the oxidized surface of patterned magnetic material  690  on the tops of the etched magnetic BPM features  660 . The side walls of the etched magnetic BPM features  660  are protected by the HSQ sacrificial filler  700  during the etch planarization process  800 . The substrate  600 , soft underlayer (SUL)  610 , and seed layer  620  are not affected by the etch planarization process  800  of one embodiment. 
     A deposition process is used to deposit an overcoat (COC) and is followed with lube, burnishing, and buffing processes  330 . The COC  810  covers the planarized exposed sections of the patterned magnetic material  690 , the etched magnetic BPM features  660 , and the remaining HSQ sacrificial filler  700 . Protecting the etched magnetic BPM features  660  during processing prevents processing-incurred structural damage of BPM features in a BPM stack  150  of one embodiment. 
       FIG. 9  shows for illustrative purposes only an example of cross-linking bake process of one embodiment.  FIG. 9  shows alternative processes continuing from  FIG. 6 . The sacrificial filler overcoating layer using resist materials  400  is used to spin the resist sacrificial filler  900  on the exposed surfaces of the seed layer  620  and surrounding the oxidized surface of patterned magnetic material  690 . The resist sacrificial filler  900  covers the etched magnetic BPM features  660 , the underlying substrate  600 , the soft underlayer (SUL)  610 , and the seed layer  620  of one embodiment. 
     The process continues using a bake process including heat and/or ultra-violet (UV) processes to harden the sacrificial filler overcoating layer  260 . The bake process includes a cross-linking bake process using ultra-violet (UV)  910  to cross-link the resist sacrificial filler  900  over the oxidized surface of patterned magnetic material  690  and the etched magnetic BPM features  660 . The bake process does not affect the substrate  600 , the soft underlayer (SUL)  610 , the and seed layer  620  of one embodiment. 
     The process includes using a planarization process to remove excess of sacrificial layer from the top of the BPM features oxidized surface  720 . The oxidized surface of patterned magnetic material  690  and etched magnetic BPM features  660  are protected by the resist sacrificial filler  900  during the planarization process. The alternative processing is further described in  FIG. 10  of one embodiment. 
       FIG. 10  shows for illustrative purposes only an example of depositing overlying, high anisotropy, continuous magnetic layer(s) of one embodiment.  FIG. 10  shows the process continuing from  FIG. 9  using a planarization process to remove excess of sacrificial layer to the top of the BPM features oxidized surface  720 . The planarization process leaves the resist sacrificial filler  900  surrounding the side walls of the etched magnetic BPM features  660  and the tops of patterned magnetic material  690 . The planarization process does not affect the substrate  600 , the soft underlayer (SUL)  610 , and the seed layer  620  of one embodiment. 
     A deposition process is used to deposit an overlying, high anisotropy, continuous magnetic layer with special magnetic properties including low reminiscence in a polar direction (perpendicular to magnetic layer) and no hysteresis in a transverse direction (parallel to magnetic layer) over the tops of the bits  410 . The overlying, high anisotropy, continuous magnetic layer  1000  is deposited on top of the patterned magnetic material  690  and remaining resist sacrificial filler  900 . A deposition process is used to deposit an overcoat (COC) and is followed with lube, burnishing, and buffing processes  330 . The COC  1010  is deposited on the overlying, high anisotropy, continuous magnetic layer  1000  of one embodiment. 
     Protecting the etched magnetic BPM features  660  during processing increases un-damaged volume of magnetic material in individual bits by preventing damage induced by processing. The increased volume and damage prevention along with the overlying, high anisotropy, continuous magnetic layer  1000  results in increased BPM magnetic quality including coercivity (Hc), perpendicular anisotropy energy (Ku), Switching Field Distribution (SFD), and others  500  of  FIG. 5 . The foregoing may also result in improved manufacturability by eliminating an oxide layer cleaning process  510  of  FIG. 5 ; improved surface topography; improved surface morphology by adding a top magnetic alloy layer  520  of  FIG. 5 ; and product robustness and fly-ability  350  of  FIG. 3  of one embodiment. 
       FIG. 11A  shows for illustrative purposes only an example of reminiscent magnetization (H-B loop shape) in polar and transverse directions for an overlying, high anisotropy, continuous magnetic layer of one embodiment.  FIG. 11A  shows a graph depicting reminiscent magnetization in polar and transverse directions for an overlying, high anisotropy, continuous magnetic layer  1100  along lines of signal values for both polar  1110  and transverse  1120  orientations configured to amplify the reminiscent magnetization of patterned magnetic features including BPM features of one embodiment. 
       FIG. 11B  shows for illustrative purposes only an example schematic of recording process of one embodiment.  FIG. 11B  shows a schematic of recording process  1130  including a read/write or r/w head  1132  including a main pole  1134  and a return pole  1136  producing a polarized signal  1138 . The magnetic flux  1138  developed by the r/w head is passed from the main pole  1134  through the COC  1170  and the overlying, high anisotropy, continuous magnetic layer  1140  and into the BPM feature  1160  with oxidized side wall  1150  protection. The magnetic flux  1128  then returns through the return pole  1136  and through the seed  1180  and the soft underlayer (SUL)  1190  of one embodiment. 
     The foregoing has described the principles, embodiments and modes of operation. However, the embodiments should not be construed as being limited to the particular embodiments discussed. The above described embodiments should be regarded as illustrative rather than restrictive, and it should be appreciated that variations may be made in those embodiments by workers skilled in the art without departing from the scope of the embodiments as defined by the following claims.