US20140353276A1 - Super shallow laminated hard mask stencil for magnetic read sensor fabrication - Google Patents
Super shallow laminated hard mask stencil for magnetic read sensor fabrication Download PDFInfo
- Publication number
- US20140353276A1 US20140353276A1 US13/907,617 US201313907617A US2014353276A1 US 20140353276 A1 US20140353276 A1 US 20140353276A1 US 201313907617 A US201313907617 A US 201313907617A US 2014353276 A1 US2014353276 A1 US 2014353276A1
- Authority
- US
- United States
- Prior art keywords
- layer
- mask
- mask layer
- forming
- stencil
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
- 230000005291 magnetic effect Effects 0.000 title description 58
- 238000004519 manufacturing process Methods 0.000 title description 2
- 238000000034 method Methods 0.000 claims abstract description 120
- 230000008569 process Effects 0.000 claims abstract description 72
- 229920002120 photoresistant polymer Polymers 0.000 claims description 79
- 239000000463 material Substances 0.000 claims description 46
- 229910052710 silicon Inorganic materials 0.000 claims description 16
- XUIMIQQOPSSXEZ-UHFFFAOYSA-N Silicon Chemical compound [Si] XUIMIQQOPSSXEZ-UHFFFAOYSA-N 0.000 claims description 15
- 239000010703 silicon Substances 0.000 claims description 15
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 claims description 13
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 claims description 12
- 229910052799 carbon Inorganic materials 0.000 claims description 12
- 229910001030 Iron–nickel alloy Inorganic materials 0.000 claims description 9
- 229910003321 CoFe Inorganic materials 0.000 claims description 8
- 239000000758 substrate Substances 0.000 claims description 7
- 239000003989 dielectric material Substances 0.000 claims description 6
- 229910052741 iridium Inorganic materials 0.000 claims description 6
- GKOZUEZYRPOHIO-UHFFFAOYSA-N iridium atom Chemical compound [Ir] GKOZUEZYRPOHIO-UHFFFAOYSA-N 0.000 claims description 6
- 238000000151 deposition Methods 0.000 claims description 5
- 229910052707 ruthenium Inorganic materials 0.000 claims description 5
- 229910010271 silicon carbide Inorganic materials 0.000 claims description 5
- KJTLSVCANCCWHF-UHFFFAOYSA-N Ruthenium Chemical compound [Ru] KJTLSVCANCCWHF-UHFFFAOYSA-N 0.000 claims description 4
- 229910004158 TaO Inorganic materials 0.000 claims description 4
- 239000000377 silicon dioxide Substances 0.000 claims description 4
- 229910004541 SiN Inorganic materials 0.000 claims 2
- 229910020286 SiOxNy Inorganic materials 0.000 claims 2
- 229910052681 coesite Inorganic materials 0.000 claims 2
- 229910052906 cristobalite Inorganic materials 0.000 claims 2
- 229910003465 moissanite Inorganic materials 0.000 claims 2
- 229910052682 stishovite Inorganic materials 0.000 claims 2
- 229910052905 tridymite Inorganic materials 0.000 claims 2
- 239000000126 substance Substances 0.000 abstract description 2
- 239000010410 layer Substances 0.000 description 430
- 238000007737 ion beam deposition Methods 0.000 description 13
- 150000002500 ions Chemical class 0.000 description 13
- 238000009413 insulation Methods 0.000 description 12
- 238000000623 plasma-assisted chemical vapour deposition Methods 0.000 description 10
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 description 9
- 239000001301 oxygen Substances 0.000 description 9
- 229910052760 oxygen Inorganic materials 0.000 description 9
- 238000004544 sputter deposition Methods 0.000 description 9
- 229910052581 Si3N4 Inorganic materials 0.000 description 8
- HQVNEWCFYHHQES-UHFFFAOYSA-N silicon nitride Chemical compound N12[Si]34N5[Si]62N3[Si]51N64 HQVNEWCFYHHQES-UHFFFAOYSA-N 0.000 description 8
- 238000000992 sputter etching Methods 0.000 description 7
- 239000007789 gas Substances 0.000 description 6
- SECXISVLQFMRJM-UHFFFAOYSA-N N-Methylpyrrolidone Chemical compound CN1CCCC1=O SECXISVLQFMRJM-UHFFFAOYSA-N 0.000 description 5
- 230000005290 antiferromagnetic effect Effects 0.000 description 5
- 239000003302 ferromagnetic material Substances 0.000 description 5
- 238000000206 photolithography Methods 0.000 description 5
- 229910052814 silicon oxide Inorganic materials 0.000 description 5
- CURLTUGMZLYLDI-UHFFFAOYSA-N Carbon dioxide Chemical compound O=C=O CURLTUGMZLYLDI-UHFFFAOYSA-N 0.000 description 4
- PNEYBMLMFCGWSK-UHFFFAOYSA-N aluminium oxide Inorganic materials [O-2].[O-2].[O-2].[Al+3].[Al+3] PNEYBMLMFCGWSK-UHFFFAOYSA-N 0.000 description 4
- 238000013459 approach Methods 0.000 description 4
- 230000015572 biosynthetic process Effects 0.000 description 4
- 239000010408 film Substances 0.000 description 4
- 230000004907 flux Effects 0.000 description 4
- 229920000642 polymer Polymers 0.000 description 4
- HBMJWWWQQXIZIP-UHFFFAOYSA-N silicon carbide Chemical compound [Si+]#[C-] HBMJWWWQQXIZIP-UHFFFAOYSA-N 0.000 description 4
- XPDWGBQVDMORPB-UHFFFAOYSA-N Fluoroform Chemical compound FC(F)F XPDWGBQVDMORPB-UHFFFAOYSA-N 0.000 description 3
- -1 NiFeCo Inorganic materials 0.000 description 3
- 238000000231 atomic layer deposition Methods 0.000 description 3
- 230000004888 barrier function Effects 0.000 description 3
- 230000008901 benefit Effects 0.000 description 3
- 230000008878 coupling Effects 0.000 description 3
- 238000010168 coupling process Methods 0.000 description 3
- 238000005859 coupling reaction Methods 0.000 description 3
- 238000009616 inductively coupled plasma Methods 0.000 description 3
- 238000003801 milling Methods 0.000 description 3
- 239000000725 suspension Substances 0.000 description 3
- 229910052715 tantalum Inorganic materials 0.000 description 3
- GUVRBAGPIYLISA-UHFFFAOYSA-N tantalum atom Chemical compound [Ta] GUVRBAGPIYLISA-UHFFFAOYSA-N 0.000 description 3
- XKRFYHLGVUSROY-UHFFFAOYSA-N Argon Chemical compound [Ar] XKRFYHLGVUSROY-UHFFFAOYSA-N 0.000 description 2
- MYMOFIZGZYHOMD-UHFFFAOYSA-N Dioxygen Chemical compound O=O MYMOFIZGZYHOMD-UHFFFAOYSA-N 0.000 description 2
- 229910003266 NiCo Inorganic materials 0.000 description 2
- 229910052786 argon Inorganic materials 0.000 description 2
- 238000001636 atomic emission spectroscopy Methods 0.000 description 2
- 229910002092 carbon dioxide Inorganic materials 0.000 description 2
- 239000001569 carbon dioxide Substances 0.000 description 2
- 238000005229 chemical vapour deposition Methods 0.000 description 2
- 238000001816 cooling Methods 0.000 description 2
- 229910001882 dioxygen Inorganic materials 0.000 description 2
- NBVXSUQYWXRMNV-UHFFFAOYSA-N fluoromethane Chemical compound FC NBVXSUQYWXRMNV-UHFFFAOYSA-N 0.000 description 2
- 229910052734 helium Inorganic materials 0.000 description 2
- 239000011810 insulating material Substances 0.000 description 2
- 229910052742 iron Inorganic materials 0.000 description 2
- 238000001459 lithography Methods 0.000 description 2
- 239000000696 magnetic material Substances 0.000 description 2
- 229910052751 metal Inorganic materials 0.000 description 2
- 239000002184 metal Substances 0.000 description 2
- 229910052759 nickel Inorganic materials 0.000 description 2
- BPUBBGLMJRNUCC-UHFFFAOYSA-N oxygen(2-);tantalum(5+) Chemical class [O-2].[O-2].[O-2].[O-2].[O-2].[Ta+5].[Ta+5] BPUBBGLMJRNUCC-UHFFFAOYSA-N 0.000 description 2
- 229910052703 rhodium Inorganic materials 0.000 description 2
- 239000010948 rhodium Substances 0.000 description 2
- 229910001936 tantalum oxide Inorganic materials 0.000 description 2
- 230000007704 transition Effects 0.000 description 2
- 229910000531 Co alloy Inorganic materials 0.000 description 1
- 229910019236 CoFeB Inorganic materials 0.000 description 1
- 229910000640 Fe alloy Inorganic materials 0.000 description 1
- YCKRFDGAMUMZLT-UHFFFAOYSA-N Fluorine atom Chemical compound [F] YCKRFDGAMUMZLT-UHFFFAOYSA-N 0.000 description 1
- 229910000990 Ni alloy Inorganic materials 0.000 description 1
- 229920001665 Poly-4-vinylphenol Polymers 0.000 description 1
- 229910019041 PtMn Inorganic materials 0.000 description 1
- 229910004481 Ta2O3 Inorganic materials 0.000 description 1
- 239000006117 anti-reflective coating Substances 0.000 description 1
- 238000001311 chemical methods and process Methods 0.000 description 1
- VNNRSPGTAMTISX-UHFFFAOYSA-N chromium nickel Chemical compound [Cr].[Ni] VNNRSPGTAMTISX-UHFFFAOYSA-N 0.000 description 1
- 150000001875 compounds Chemical class 0.000 description 1
- 238000004590 computer program Methods 0.000 description 1
- 239000012141 concentrate Substances 0.000 description 1
- 229910052593 corundum Inorganic materials 0.000 description 1
- 238000013500 data storage Methods 0.000 description 1
- 230000008021 deposition Effects 0.000 description 1
- 238000005137 deposition process Methods 0.000 description 1
- 239000002355 dual-layer Substances 0.000 description 1
- 238000005530 etching Methods 0.000 description 1
- 229910052731 fluorine Inorganic materials 0.000 description 1
- 239000011737 fluorine Substances 0.000 description 1
- 238000010438 heat treatment Methods 0.000 description 1
- 239000001307 helium Substances 0.000 description 1
- SWQJXJOGLNCZEY-UHFFFAOYSA-N helium atom Chemical compound [He] SWQJXJOGLNCZEY-UHFFFAOYSA-N 0.000 description 1
- 230000005415 magnetization Effects 0.000 description 1
- 229910001120 nichrome Inorganic materials 0.000 description 1
- 239000011368 organic material Substances 0.000 description 1
- TWNQGVIAIRXVLR-UHFFFAOYSA-N oxo(oxoalumanyloxy)alumane Chemical compound O=[Al]O[Al]=O TWNQGVIAIRXVLR-UHFFFAOYSA-N 0.000 description 1
- 238000002294 plasma sputter deposition Methods 0.000 description 1
- 238000007747 plating Methods 0.000 description 1
- MHOVAHRLVXNVSD-UHFFFAOYSA-N rhodium atom Chemical compound [Rh] MHOVAHRLVXNVSD-UHFFFAOYSA-N 0.000 description 1
- 238000007493 shaping process Methods 0.000 description 1
- 235000012239 silicon dioxide Nutrition 0.000 description 1
- 238000004528 spin coating Methods 0.000 description 1
- PBCFLUZVCVVTBY-UHFFFAOYSA-N tantalum pentoxide Inorganic materials O=[Ta](=O)O[Ta](=O)=O PBCFLUZVCVVTBY-UHFFFAOYSA-N 0.000 description 1
- 239000010409 thin film Substances 0.000 description 1
- 229910001845 yogo sapphire Inorganic materials 0.000 description 1
Images
Classifications
-
- G—PHYSICS
- G11—INFORMATION STORAGE
- G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
- G11B5/00—Recording by magnetisation or demagnetisation of a record carrier; Reproducing by magnetic means; Record carriers therefor
- G11B5/127—Structure or manufacture of heads, e.g. inductive
- G11B5/33—Structure or manufacture of flux-sensitive heads, i.e. for reproduction only; Combination of such heads with means for recording or erasing only
- G11B5/39—Structure or manufacture of flux-sensitive heads, i.e. for reproduction only; Combination of such heads with means for recording or erasing only using magneto-resistive devices or effects
- G11B5/3903—Structure or manufacture of flux-sensitive heads, i.e. for reproduction only; Combination of such heads with means for recording or erasing only using magneto-resistive devices or effects using magnetic thin film layers or their effects, the films being part of integrated structures
- G11B5/398—Specially shaped layers
-
- G—PHYSICS
- G11—INFORMATION STORAGE
- G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
- G11B5/00—Recording by magnetisation or demagnetisation of a record carrier; Reproducing by magnetic means; Record carriers therefor
- G11B5/127—Structure or manufacture of heads, e.g. inductive
-
- G—PHYSICS
- G11—INFORMATION STORAGE
- G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
- G11B5/00—Recording by magnetisation or demagnetisation of a record carrier; Reproducing by magnetic means; Record carriers therefor
- G11B5/127—Structure or manufacture of heads, e.g. inductive
- G11B5/31—Structure or manufacture of heads, e.g. inductive using thin films
- G11B5/3163—Fabrication methods or processes specially adapted for a particular head structure, e.g. using base layers for electroplating, using functional layers for masking, using energy or particle beams for shaping the structure or modifying the properties of the basic layers
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
- Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
- Y10T29/00—Metal working
- Y10T29/49—Method of mechanical manufacture
- Y10T29/49002—Electrical device making
- Y10T29/4902—Electromagnet, transformer or inductor
- Y10T29/49021—Magnetic recording reproducing transducer [e.g., tape head, core, etc.]
- Y10T29/49032—Fabricating head structure or component thereof
Definitions
- Embodiments of the present invention generally relate to methods of making a magnetic read sensor. More particularly, embodiments of the present invention relate to methods of making a magnetic read sensor utilizing a super shallow laminated hard mask stencil.
- the heart of a computer is a magnetic disk drive which typically includes a rotating magnetic disk, a slider that has read and write heads, a suspension arm above the rotating disk and an actuator arm that swings the suspension arm to place the read and/or write heads over selected circular tracks on the rotating disk.
- the suspension arm biases the slider towards the surface of the disk when the disk is not rotating but, when the disk rotates, air is swirled by the rotating disk and the adjacent air bearing surface (ABS) of the slider causes the slider to ride on an air bearing with a slight distance from the surface of the rotating disk.
- ABS air bearing surface
- the write and read heads are employed for writing magnetic impressions to and reading magnetic signals from the rotating disk.
- the read and write heads are connected to processing circuitry that operates according to a computer program to implement the writing and reading functions.
- a plurality of sensor layers are deposited across the surface of a substrate.
- One or more mask layers are deposited over the sensor layers and a series of photolithographic processes and reactive ion etch (RIE) processes are then conducted to form a mask stencil above the sensor layers.
- RIE reactive ion etch
- An ion milling process then removes unmasked portions of the sensor layers to define the shape, profile and dimension (such as track width) of the read head sensor.
- the present invention generally relates to methods for forming a sensor structure utilizing a shallow and narrow hard mask stencil.
- a sensor structure is formed by utilizing a four-layered hard mask stencil.
- the four-layered hard mask stencil includes a first mask layer, a second mask layer disposed over the first hard mask, a third mask layer disposed over the second mask layer, and a forth mask layer disposed over the third mask layer.
- a sensor structure is formed by utilizing a three-layered hard mask stencil.
- the three-layered hard mask stencil includes a first mask layer, a second mask layer disposed over the first mask layer, and a third mask layer disposed over the second mask layer.
- the sensor structure is formed with a two-step chemical mechanical planarization (CMP) process.
- CMP chemical mechanical planarization
- a method for forming a read head includes forming a sensor layer on a substrate, forming a first mask layer over the sensor layer; forming a patterned bi-layer structure over a portion of the first mask layer, forming a RIE (reactive ion etch) stop layer over the first mask layer and the bi-layer structure, and removing the bi-layer structure and the portion of the RIE stop layer disposed over the bi-layer structure to expose a portion of the first mask layer.
- the area covered by the RIE stop layer is called the field area, and the area not covered by the RIE stop layer is called the device area.
- the method further includes forming a second mask layer over RIE stop layer (i.e., in the field area) and also over the exposed first mask layer (i.e., in the device area), forming a third mask layer over the second mask layer, forming a fourth mask layer over the third mask layer, forming a patterned photoresist mask in the device area using lithography process over the fourth mask layer, leaving portions of the device area and the entire field area exposed, then removing a portion of the fourth mask layer using a first RIE with certain amount of over-etch that the fourth mask layer is completely etched through in the area not protected by the photoresist mask and exposing portion of the third mask layer.
- the method further includes applying a second RIE process, which capable of selectively etch the photoresist mask, the third, the second and the first mask layer without (or with minimum) etch to the fourth mask layer and the RIE stop layer, forming a hard mask stencil (in the device area) consisting of four mask layers (i.e., the fourth, the third, the second, and the first mask layer) without photoresist residue disposed thereon.
- the device area is further divided into two areas, one is the stencil, another is channel area where the header sensor is not covered by the stencil and is exposed.
- the stencil is surrounded by the channel area.
- the third and second mask layer in the field area are also removed in the second RIE process, however the first mask layer in the field is not etched by the second RIE since the first mask layer is protected by the RIE stop layer.
- the method further includes forming a patterned photoresist mask on the RIE stop layer and leaving device area (including stencil and channel area) exposed. Thereafter an ion mill process is performed, the sensor layer in the channel area is etched away, the sensor layer under the stencil is protected by the stencil, and a reader sensor junction shape is formed under the stencil.
- the third mask layer of the stencil and partial of the second layer of the stencil are consumed during ion mill process, and the remaining of the second mask layer and first mask layer are still on the stencil.
- the RIE stop layer and the first mask layer in the field area is protected by the photoresist mask thus not etched by the ion mill, however, portions of the photomask are consumed in the ion mill.
- the method further includes forming an dielectric insulation layer (or layers) covering remaining stencil, channel areas and photoresist in field area, forming a hard bias layer on top of the dielectric layer, forming a cap layer on hard bias layer, removing the cap layer, the hard bias layer and the dielectric layer in the field area by a liftoff process to expose the RIE stop layer over the field area, removing the cap layer, the hard bias layer, the dielectric layer and the second mask layer of the stencil by a CMP process, exposing the first mask layer of the stencil, at the same time exposing the first mask layer in the field area, and partially removing the cap layer in the channel areas.
- a third RIE process is performed to remove the exposed first mask layer in both stencil and field area and the remaining cap layer in the channel areas, thus forming a reader junction sensor.
- a method for forming a read head includes forming a sensor layer on a substrate, forming a cap layer over the sensor layer, forming a first mask layer having a first thickness over the cap layer, forming a second mask layer over the first mask layer, forming a third mask layer over the second mask layer, forming a patterned photoresist mask using lithography process over the third mask layer, leaving the rest of the device area exposed, removing a portion of the third mask layer not protected by the photoresist mask using a first reactive ion etch (RIE) with certain amount of over-etch that both the third layer and the second layer in the field area and in the channel area are completely etched through and exposing portion of the first mask layer in the field area and channel area.
- the first RIE process forms a stack in the device area consisting of residual photoresist, the third and the second mask layer, and part of the first layer. The stack is disposed on a remaining first mask layer having a second thickness.
- a patterned photoresist mask is formed on the remaining first mask layer in the field area leaving the device area (i.e., the stack and the surrounding channel areas) exposed.
- the method further includes removing a portion of the remaining first mask layer in the channel areas using a second RIE process to etch away the remaining first mask layer in the channel areas, forming a hard mask stencil since the high etch selectivity of the third mask layer on the stencil, and leaving the photoresist mask in the field area partially etched with a remaining of thickness that is sufficient for the liftoff process later. Thereafter an ion mill process is performed to mill away the exposed sensor layer in the channel areas and a reader sensor junction shape is formed.
- the method further includes forming an dielectric insulation layer (or layers) covering the stencil, device area and photoresist in field area, forming a side-shield layer on top of the dielectric layer, removing the side-shield layer and the dielectric layer in the field area by a liftoff process to expose the first mask layer having a second thickness over the field area, removing the side-shield layer and dielectric layer and the second mask layer of the stencil by a first CMP process, and exposing the first mask layer of the stencil.
- the exposed first mask layer in the field has high CMP selectivity thus only partially removed.
- the method further includes removing the exposed first mask layer in field and the first mask layer on the stencil using a third RIE process to expose the cap layer in both stencil and filed area.
- the method further includes applying a second CMP to polish the portion of the side-shield.
- the cap layer has higher CMP selectivity that the bump-out side-shield is planarized and has the same flat surface with cap layer. Then an ion mill process with the same mill rate is used to remove the cap layer and portions of the side-shield, and a sensor junction is formed.
- FIG. 1 illustrates an exemplary magnetic disk drive, according to an embodiment of the invention.
- FIG. 2A is a side view of a read/write head and magnetic disk of the disk drive of FIG. 1 , according to one embodiment of the invention.
- FIG. 2B is a schematic cross-sectional view of portions of the magnetic head according to one embodiment.
- FIGS. 3A-3P illustrate the process of making a sensor structure of FIG. 2B according to one embodiment.
- FIGS. 4A-4M illustrate the process of making the sensor structure of FIG. 2B according to another embodiment.
- the present invention generally relates to methods for forming a magnetic sensor structure utilizing a shallow and narrow hard mask stencil.
- a sensor structure is formed by utilizing a four-layered hard mask stencil.
- the four-layered hard mask stencil includes a first mask layer, a second mask layer (a release layer), a third mask layer and a fourth mask layer.
- a sensor structure is formed by utilizing a three-layered hard mask stencil.
- the three-layered hard mask stencil includes a first mask layer, a second mask layer, and a third mask layer.
- the sensor structure is formed with a two-step CMP process.
- FIG. 1 illustrates a top view of an exemplary HDD 100 , according to an embodiment of the invention.
- HDD 100 may include one or more magnetic disks 110 , actuator 120 , actuator arms 130 associated with each of the magnetic disks, and spindle motor 140 affixed in a chassis 150 .
- the one or more magnetic disks 110 may be arranged vertically as illustrated in FIG. 1 .
- the one or more magnetic disks may be coupled with the spindle motor 140 .
- Magnetic disks 110 may include circular tracks of data on both the top and bottom surfaces of the disk.
- a magnetic head 180 mounted on a slider may be positioned on a track. As each disk spins, data may be written on and/or read from the data track.
- Magnetic head 180 may be coupled to an actuator arm 130 as illustrated in FIG. 1 .
- Actuator arm 130 may be configured to swivel around actuator axis 131 to place magnetic head 180 on a particular data track.
- FIG. 2A is a fragmented, cross-sectional side view through the center of a read/write head 200 mounted on a slider 201 and facing magnetic disk 202 .
- the read/write head 200 and the magnetic disk 202 may correspond to the magnetic head 180 and the magnetic disk 110 , respectively in FIG. 1 .
- 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 (PL) 206 formed on a disk substrate 208 .
- RL perpendicular magnetic data recording layer
- PL magnetically permeable underlayer
- the read/write head 200 includes an ABS, a magnetic write head 210 and a magnetic read head 211 , and is mounted such that the ABS is facing the magnetic disk 202 .
- 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 .
- the magnetic read head 211 is a magnetoresistive (MR) read head that includes an MR sensing element 230 located between MR shields S1 and S2.
- the magnetic read head 211 is a magnetic tunnel junction (MTJ) read head that includes a MTJ sensing device 230 located between MR shields S1 and S2.
- 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 (or MTJ) sensing element 230 as the recorded bits.
- the write head 210 includes a magnetic circuit made up of a main pole 212 and a yoke 216 .
- the write head 210 also includes a thin film coil 218 shown in the section embedded in a non-magnetic material 219 and wrapped around yoke 216 .
- the yoke 216 may be omitted, and the coil 218 may wrap around the main pole 212 .
- a write pole 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 .
- 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.
- 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 .
- the distance between the flare point 222 and the ABS is between about 0 nm and about 150 nm.
- the write pole 220 includes a tapered surface 271 which increases a width of the write pole 220 from a first width W1 at the ABS to a second width W2 away from the ABS.
- the width W1 may be between about 60 nm and 200 nm
- the width W2 may be between about 120 nm and 350 nm.
- the tapered region 271 is shown with a single straight surface in FIG. 2A , in alternative embodiment, the tapered region 271 may include a plurality of tapered surface with different taper angles with respect to the ABS.
- the tapering improves magnetic performance. For example, reducing the width W1 at the ABS may concentrate a magnetic field generated by the write pole 220 over desirable portions of the magnetic disk 202 . In other words, reducing the width W1 of the write pole 220 at the ABS reduces the probability that tracks adjacent to a desirable track are erroneously altered during writing operations.
- a larger width W2 of the write pole 220 away from the ABS may desirably increase the magnetic flux to the write pole 220 , by providing a greater thickness of the write pole 220 in a direction generally parallel to the ABS.
- write current passes through coil 218 and induces a magnetic field (shown by dashed line 228 ) from the write pole 220 that passes through the RL 204 (to magnetize the region of the RL 204 beneath the write pole 220 ), through the flux return path provided by the PL 206 , and back to an upper return pole 250 .
- the greater the magnetic flux of the write pole 220 the greater is the probability of accurately writing to desirable regions of the RL 204 .
- FIG. 2A further illustrates one embodiment of the upper return pole 250 that is separated from write pole 220 by a nonmagnetic gap layer 256 .
- the upper return pole 250 may be a trailing shield wherein substantially all of the shield material is on the trailing end 203 .
- the upper return pole 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 .
- FIG. 2A is a cross section through the center of the read/write head 200 , it represents both trailing and wrap-around embodiments.
- 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 write pole 220 and the upper return pole 250 at the ABS.
- the upper return pole 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 throat 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 layer that allows for greater magnetic flux density from the write pole 220 , while avoiding saturation of the upper return pole 250 .
- the taper 260 may extend either more or less than is shown in FIG. 2A .
- the taper may extend upwards to an end of the upper return pole 250 opposite the ABS (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 the ABS to greater thicknesses at a first distance from the ABS, to a greatest thickness at a second distance (greater than the first distance) from the ABS.
- FIG. 2B is a schematic cross-sectional view of portions of magnetic head 211 according to one embodiment.
- the thickness and the width of each layer are for example only, and each layer may be thicker/thinner and/or wider/narrower.
- the magnetic head 211 includes a first shield layer 231 .
- the first shield layer 231 may comprise a ferromagnetic material. Suitable ferromagnetic materials that may be utilized include Ni, Fe, Co, NiFe, NiFeCo, NiCo, CoFe and combinations thereof.
- the magnetic head 211 also includes a sensor structure 205 comprising a pinned magnetic layer 233 , a barrier layer 234 , a free layer 236 and an optional capping layer 238 .
- the pinned magnetic layer 233 may be one of several types of pinned layers, such as a simple pinned, antiparallel pinned, self pinned or antiferromagnetic pinned. For purposes of simplicity, the sensor will be described herein as antiparallel pinned.
- the antiferromagnetic pinned sensor has a first antiparallel pinned layer, a second antiparallel pinned layer, and a non-magnetic, antiferromagnetic coupling layer, such as Ru sandwiched between the two pinned layers.
- the first and second antiparallel pinned layers can be constructed of several magnetic materials, such as NiFe or CoFe, and have magnetic moments that are pinned by exchange coupling of the first antiparallel pinned layer with an antiferromagnetic layer.
- the antiferromagnetic layer may include materials such as PtMn, iridium, or rhodium.
- the barrier layer 234 may comprise an insulating material such as MgO or alumina.
- the free layer 236 may comprise ferromagnetic material such as Co, CoFe, CoFeB, NiFe or combinations thereof.
- the capping layer 238 may comprise a material to protect the sensor from damage such as ruthenium, iridium, tantalum or combinations thereof.
- an insulating layer 240 may be deposited on the first shield layer 231 as well as the sidewalls of the sensor structure 205 .
- the insulating layer 240 may comprise an insulating material such as aluminum oxide, silicon nitride or silicon oxide.
- the insulating layer 240 may be deposited by well known deposition methods such as atomic layer deposition (ALD), chemical vapor deposition (CVD), sputtering, ion beam deposition (IBD) and etc.
- ALD atomic layer deposition
- CVD chemical vapor deposition
- IBD ion beam deposition
- a hard bias or a soft side-shield layer 242 is then deposited.
- the hard bias layer or soft side-shield 242 may comprise a material having a high magnetic moment such as CoFe or NiFe.
- a capping structure 244 may be formed.
- the capping structure 244 may comprise a multiple layer structure comprising a first tantalum layer, an iridium layer, and a second tantalum layer.
- a second shield layer 246 may be deposited over the capping structure 244 and the sensor structure 205 .
- the second shield layer 246 may comprise a ferromagnetic material. Suitable ferromagnetic materials that may be utilized include Ni, Fe, Co, NiFe, NiFeCo, NiCo, CoFe and combinations thereof.
- a hard mask stencil is formed over the layers 233 , 234 , 236 and 238 to help shaping the sensor structure 205 .
- a conventional mask stencil has a height of about 100 nanometers (nm) and a width of about 30 to 40 nm.
- a shallower and narrower hard mask stencil with better control on both track width and height within wafer and wafer to wafer should be utilized.
- FIGS. 3A-3P illustrate the process of making the sensor structure 205 utilizing such shallow and narrow hard mask stencil.
- the sensor layer 302 is deposited over the first shield layer 231 .
- the sensor layer 302 may include the pinned magnetic layer 233 , the barrier layer 234 , the free layer 236 and the optional capping layer 238 .
- a first mask layer 304 is deposited over the sensor layer 302 .
- the first mask layer 304 may be a diamond-like carbon (DLC) layer that is deposited by plasma enhanced chemical vapor deposition (PECVD), ion beam deposition (IBD), or any other suitable deposition process.
- PECVD plasma enhanced chemical vapor deposition
- IBD ion beam deposition
- the first mask layer 304 is deposited by IBD and has a thickness of about 3 nm to about 8 nm.
- the first mask layer 304 is to serve as a CMP stop layer as discussed below.
- a bi-layer structure 306 is deposited over the first mask layer 304 .
- the bi-layer structure 306 includes a release layer 308 and a photoresist layer 310 .
- the release layer 308 may be polydimethylglutarimide (PMGI) and the photoresist layer 310 may be a polyphenolic polymer or polyvinylphenol.
- Gaps (or undercuts) 307 and 309 are formed between the photoresist layer 310 and the first mask layer 304 at the bottom of the bi-layer structure 306 .
- an RIE stop layer 312 (as will be discussed in detail later) is deposited over the uncovered portions of the first hard mask layer 304 and the photoresist layer 310 .
- the RIE stop layer 312 also covers the side walls of the photoresist layer 310 ; however, the undercuts 307 , 309 are not sealed in by the RIE stop layer 312 because of the gap 307 and 309 .
- the RIE stop layer 312 may be silicon nitride (SiN), tantalum oxides (TaO, Ta 2 O 3 , Ta 2 O 5 ), silicon carbide (SiC), silicon dioxide (SiO 2 ), silicon oxynitride (SiO x N y ), or other suitable material.
- the RIE stop layer 312 is SiN having a thickness of about 2 nm to 8 nm and is deposited by ALD, PECVD, IBD, or sputtering method.
- the bi-layer structure 306 is subjected to a photoresist stripper for dissolving the release layer 308 and releasing the photoresist layer 310 from the first mask layer 304 .
- the photoresist stripper dissolves the release layer 308 and photoresist layer 310 by entering into the undercuts 307 , 309 .
- An exemplary photoresist stripper for the release layer 308 and the photoresist layer 310 is N-methyl pyrrolidone (NMP).
- NMP N-methyl pyrrolidone
- a second mask layer 314 is deposited on the exposed first hard mask layer 304 (device area) and on the RIE stop layer 312 (field area).
- the second mask layer 314 is a polymer-like carbon (PLC), which is much softer than DLC of the first mask layer 304 , and has a thickness of about 5 nm to about 10 nm over the first mask layer 304 and can be deposited by either PECVD or IBD method.
- the second mask layer 314 serves as a release layer in the CMP process as discussed below in detail.
- a third mask layer 316 is deposited over the second mask layer 314 , as shown in FIG. 3F .
- the third mask layer 316 is a material that has a low milling rate, such as C or DLC and has a thickness of about 5 nm to about 10 nm.
- the third mask layer 316 may be deposited by any suitable process, such as IBD, PECVD or sputtering.
- a fourth mask layer 318 is deposited over the third mask layer 316 .
- the fourth mask layer 318 may be a dielectric film or a thin metal layer.
- the fourth mask layer 318 is a dielectric hard mask layer.
- the dielectric hard mask layer 318 may be constructed of a dielectric material and is preferably constructed of a silicon-containing hard mask material such as silicon oxide, silicon nitride, silicon oxynitride which may be deposited using PECVD, IBD or sputtering method, or a silicon-containing organic material such as SIHM® (Shin-Etsu Chemical Co., Ltd.) or UVAS (Honeywell International Inc.) and etc, which may be spin-coated on and cured at elevated temperature from 150 degrees Celsius to 250 degrees Celsius.
- the thickness of the dielectric hard mask layer 318 may depend on the total thickness of the first mask layer 304 , the second mask layer 314 and the third mask layer 316 .
- the thicker the total thickness of 304 , 314 and 316 the thicker the dielectric hard mask layer 318 will preferably be.
- the typical thickness of the silicon containing dielectric hard mask layer 318 is about 5 nm to about 30 nm.
- an optional bottom anti-reflective coating may be deposited over the dielectric hard mask layer 318 .
- the determination of whether a BARC layer is desirable depends on the requirements of the photolithograph and on the material used for the dielectric hard mask layer 318 . For example, if the dielectric hard mask layer 318 is a material that acts as a BARC, then no BARC layer is deposited. Such materials include silicon oxynitride, SIHM® (Shin-Etsu Chemical Co., Ltd.), UVAS (Honeywell International Inc.), and etc.
- BARC is desirable to control photolithography parameters such as reflective swing and photo CDs
- a BARC layer is deposited by any suitable deposition method such as spin coating and then baking.
- the dielectric hard mask layer 318 represents both the mask layer and the BARC layer if any.
- a photoresist layer 352 is deposited over the dielectric hard mask layer 318 .
- a photolithography process is then performed to form a photoresist mask in which only a small portion of the photoresist layer 352 remains on the dielectric hard mask layer 318 in the device area, as shown in FIG. 3H , and the remaining portion of the dielectric hard mask layer 318 is exposed.
- a first RIE process is performed to remove portions of the dielectric hard mask layer 318 that are not protected by the photoresist mask 352 , as shown in FIG. 3I .
- the RIE may use fluorocarbon based gas chemistry mixed with other gases as etchants to perform the etching.
- this RIE may preferably be performed in a fluorine containing plasma chemistry such as one that contains CF 4 , CHF 3 , Ar, He, O 2 and etc., a combination thereof, or any other compound which would be apparent to one skilled in the art upon reading the present description.
- the first RIE may additionally include transferring the image of the photoresist mask 352 onto the under-lying dielectric hard mask layer 318 by removing portions of the dielectric hard mask layer 318 that are not protected by the photoresist mask 352 , leaving a structure as shown in FIG. 3I .
- Plasma-Therm's VERSALOCK® etcher which is an inductively coupled plasma (ICP) etch system in which the plasma is generated by means of inductively coupling 2 MHz RF power (the source power) while independently controlling the ion energy directed toward the substrate via 13.56 MHz bias power.
- ICP inductively coupled plasma
- the VERSALOCK® etcher is equipped with an Optical Emission Spectrometry (OES) endpoint system that allows precise control of the over-etch amount via the determination of etch endpoint.
- OFES Optical Emission Spectrometry
- ICP etchers equipped with both source and bias power supplies, such as TCP9400DFM® from Lam Research Inc., or DPS® from Applied Materials Inc., can also be used for RIE the dielectric hard mask material and polymer mask under-layer. It is expected that the RIE process presented herein can be used in conjunction with many different ICP etchers.
- the percentage of the over etch time can be ranging from 20% to 60%.
- the pattern of the photoresist mask layer 352 is transferred onto the dielectric hard mask layer 318 , and part of the photoresist mask 352 is consumed during the first RIE.
- the image of the dielectric hard mask 318 may be transferred onto the layer disposed thereunder (i.e., layers 316 , 314 and 304 ) using a second RIE which may have a different material selectivity than the first RIE, to form a stencil consisting of layers 318 , 316 , 314 and 304 .
- the second RIE is an oxygen or carbon dioxide based RIE.
- the preferable oxygen gas flow is about 5 sccm to 20 sccm, and the carbon dioxide gas flow is about 15 sccm to 50 sccm.
- the photoresist layer 352 remaining from the first RIE (and optional BARC layer if any) is etched away completely during the second RIE. Since the dielectric hard mask layer 318 has much slower etch rate (or high etch rate selectivity), only a small portion of the dielectric hard mask 318 is consumed, thus the mask pattern of the dielectric hard mask layer 318 is transferred to the third mask layer 316 , the second mask layer 314 and the first mask layer 304 , the portion of these three layers which are not protected by the dielectric hard mask layer 318 are etched away in the device area, and the remaining layers in the device area form a hard mask stencil 320 .
- the cap layer 312 is a kind of dielectric layer and also has high etch selectivity (i.e., it doesn't etch by oxygen based plasma)
- the second RIE stops on the cap layer 312 in the field area, thus the first mask layer 304 under the cap layer 312 is not etched, as shown in FIG. 3J .
- the hard mask stencil 320 is formed in the device area, as shown in FIG. 3J . Portions of the sensor layer 302 are exposed while the remaining portions of the sensor layer 302 are covered by the hard mask stencil 320 (in device area) and the first mask layer 304 (in field area).
- the resulting hard mask stencil 320 includes four layers and has a height (thickness) between about 30 nm and about 65 nm and a width between about 10 nm to about 30 nm. In one embodiment, the hard mask stencil 320 has a height of about 45 nm.
- the hard mask stencil 320 provides better wafer to wafer and within wafer control on mill stencil CD uniformity and height by combining both low RIE and low milling etch rate mask layers.
- the reduced height of the hard mask stencil 320 helps with symmetric junction shape formation and the narrow width of the hard mask stencil 320 helps with narrow track width read sensor fabrication.
- a photoresist mask layer 330 is fabricated.
- the field area which is protected by the cap layer 312 is completely covered by the photoresist 330 , and the device area (including the stencil 320 ) is exposed and has no photoresist over it at all, as shown in FIG. 3K .
- the thickness of the photoresist 330 is about 150 nm to 300 nm.
- channels 332 , 334 are formed in the sensor layer 302 , and a tapered reader sensor stack 205 is formed under the stencil 320 , as shown in FIG. 3L .
- the entire fourth mask layer 318 and a portion of the third mask layer 316 of the hard mask stencil 320 are consumed as a result of the ion milling process, and portions of the photoresist mask 330 are also removed in the ion mill.
- the remaining thickness of the photoresist mask layer 330 is about 50 nm to about 200 nm.
- an insulation dielectric layer 338 is first deposited as an insulation layer, followed by a magnetic hard bias (or soft side-shield) material 340 deposition into the channels 332 , 334 and over the photoresist layer 330 and the top of the hard mask stencil 320 .
- the insulation layer 338 and the hard bias (or soft side-shield) material 340 also cover side walls of the stencil 320 , side walls of sensor 205 and side walls of photoresist mask 330 .
- the suitable materials for the insulation layer can be various dielectric films such as silicon nitride, alumina, silicon oxide, tantulum oxide, silicon carbride, with thickness from about 2 nm to about 10 nm, and can be deposited by sputtering, PECVD or IBD method.
- the hard bias (or soft side-shield) material 340 may be a material that has a high magnetic moment such as CoFe or NiFe which can be deposited by sputtering method.
- Another optional layer 360 may be deposited over the hard bias (or soft side-shield) material 340 .
- the optional layer 360 may be diamond-like carbon, and has a thickness of about 2 nm to about 10 nm.
- the photoresist mask 330 along with the optional layer 360 , the hard bias (or soft side-shield) material 340 , and the insulation layer 338 covering the top and the side of the photoresist mask 330 may be removed. The removal may be achieved by first baking the structure at elevated temperature such as about 90 degrees Celsius to about 180 degrees Celsius and then cooling the structure rapidly, followed by one or more rounds of hot NMP liftoff.
- cracks are formed on the optional layer 360 , the hard bias (or soft side-shield) material 340 and insulation layer 338 , thus allowing the hot NMP at temperature from about 60 degrees Celsius to about 90 degrees Celsius to reach the covered photoresist mask 330 to liftoff the photoresist mask 330 and everything on the photoresist mask 330 in the field area.
- the RIE stop layer 312 and the first mask layer 304 are remaining in the field area.
- the sensor 205 , stencil 320 , insulation layer 338 , hard bias layer (or soft side-shield) 340 and optional layer 360 are still remaining in the device area.
- a CMP process is performed.
- the CMP process removes the RIE stop layer 312 and stops on the first mask layer 304 since the dielectric material of the RIE stop layer 312 can be polished much faster than the DLC material of the first mask layer 304 .
- the CMP is only removing a small portion of the optional layer 360 since the optional layer 360 is DLC material, thus protects the hard bias (or soft side-shield) material 340 .
- the stencil 320 since the second mask layer 314 is a polymer like carbon which is much soft than the DLC material of the first mask layer 304 , when a CPM process is applied, the stencil breaks at the interface between the second mask layer 314 and the first mask layer 304 . Anything on the stencil 320 above the first mask layer 304 is removed.
- the exposed surface in the channels 332 and 334 of the device area comprises the optional layer 360
- the exposed surface of the stencil comprises the first mask layer 304
- the exposed surface in the field also comprises the first mask layer 304 , as illustrated in FIG. 3O .
- the above discussed removal process is achieved by a CMP process and thus is called CMP assisted liftoff.
- the resulting planar surface includes the first mask layer 304 (in both field area and on the sensor) and the optional layer 360 .
- the remaining DLC film of the first mask layer 304 and the optional layer 360 are removed by an oxygen based RIE process, exposing the cap layer of the sensor structure 205 in device area, the hard bias (or soft side-shield) layer 340 and the sensor layer 302 in the field area.
- the top magnetic shield layer composed with NiFe is then deposited with sputtering method or metal plating method, and more subsequent processes are performed to fabricate a magnetic recording sensor.
- FIGS. 3A-3P illustrate one manner of making a sensor structure utilizing a shallow and narrow hard mask stencil.
- FIGS. 4A-4M illustrate an alternative way of making the sensor structure utilizing a different shallow and narrow hard mask stencil.
- the sensor layer 302 is deposited over the first shield layer 231 .
- a cap layer 402 is deposited over the sensor layer 302
- a first mask layer 404 is deposited over the cap layer 402 .
- the cap layer 402 is iridium (Ir) and has a thickness of about 2 nm to about 6 nm and can be deposited using sputtering method.
- Ru ruthenium
- the first mask layer 404 may be a diamond-like carbon layer having a thickness between about 10 nm and about 50 nm and can be deposited using either PECVD or IBD process.
- a second mask layer 406 is deposited over the first mask layer 404 and a third mask layer 408 is deposited over the second mask layer 406 .
- the second mask layer 406 is a dielectric material such as silicon oxide and has a thickness of about 5 nm to about 20 nm.
- suitable dielectric materials such as silicon, silicon nitride, silicon carbide, silicon oxynitride or tantalum oxide.
- the dielectric material 406 can be deposited using PECVD, IBD or sputtering method.
- the third mask layer 408 may be a regular non-silicon based BARC layer or a silicon based BARC layer such as SIHM® (Shin-Etsu Chemical Co., Ltd.), UVAS (Honeywell International Inc.) and etc., with a thickness ranging from about 20 nm to 60 nm.
- a photoresist layer is coated and baked over the third mask layer 408 , a photolithography process is performed, and a photoresist mask 409 is formed on the third mask layer 408 , exposing portions of the third mask layer, as shown in FIG. 4C .
- a first RIE process containing fluorocarbon such as CF 4 /CHF 3 mixed with other gases such as oxygen, argon and helium is performed.
- Portions of the third mask layer 408 not protected by the photoresist mask 409 is etched away, and with continuing of the RIE, a portion of the second mask layer 406 and a portion of the first mask layer 404 not protected by the photoresist mask 409 are also removed.
- the third mask layer 408 and the second mask layer 406 are etched through in the area not protected by the photoresist mask 409 , the first mask layer is not etched through.
- the RIE process stops on the first mask layer 404 , and the etch depth of the first mask layer 404 depends on the total over etch amount of the third and second mask layers 408 , 406 .
- a portion of the photoresist mask 409 is consumed in the first RIE and the thickness is reduced.
- the remaining photoresist mask 409 , the third mask 408 , the second mask layer 406 , and a portion of the first mask layer 404 form a stack 411 .
- a portion of the first mask layer 404 having the entire width “W” and depth “D” is not affected by this first RIE and is labeled with 410 .
- the stack 411 sits on a mask layer 410 that has a thickness less than the first mask layer 404 .
- the thickness of the mask layer 410 is half of the first mask layer 404 .
- the remaining photoresist layer 409 may or may not be removed by a wet strip process depending on the needs.
- a photoresist layer is then coated and baked, and a photolithography is performed to form a photoresist assisted CMP (PAC) photoresist mask 412 on the first mask layer 410 , as shown in FIG. 4E .
- the photoresist mask 412 covers only the field area, leaving the stack 411 and surrounding area (i.e., channel areas formed in the ion mill as discussed later) exposed.
- the channel areas i.e., the portions of the mask layer 410 neither protected by the photoresist layer 412 nor the stack 411 ) is removed by a second RIE process based on the oxygen plasma chemistry, exposing the cap layer 402 in the channel areas.
- the PAC photoresist mask 412 is applied with enough thickness that there is sufficient remaining PAC photoresist mask 412 leftover in the field area.
- the remaining photoresist mask 409 is completely removed in the second RIE process, and the second RIE is stopped on the third mask layer 408 if the third mask layer 408 is a silicon based BARC material such as SIHM® (Shin-Etsu Chemical Co., Ltd.), UVAS (Honeywell International Inc.), which has high etch selectivity so only a small amount of the top portion is etched away.
- a hard mask stencil 420 consisting of the third mask layer 408 , the second mask layer 406 and the first mask layer 404 , is formed, as shown in FIG. 4F .
- the hard mask stencil 420 has a width between about 10 nm and about 30 nm and a height between about 20 nm and about 60 nm. In one embodiment, the hard mask stencil 420 has a height of about 40 nm.
- an ion milling is performed to remove portions of the cap layer 402 and the sensor layer 302 not protected by the photoresist layer 412 and the hard mask stencil 420 .
- Channels 432 and 434 in the sensor layer 302 are formed and portions of the first shield layer 231 are exposed, as shown in FIG. 4G .
- the third mask layer 408 , the second mask layer 406 , and a portion of the first mask layer 404 of the hard mask stencil 420 are also consumed as a result of the ion milling process.
- a mask layer 436 disposed above the sensor structure 205 is a mask layer 436 , which is the remaining portion of the first mask layer 404 and the cap layer 402 .
- Portion of the photoresist mask layer 412 is also consumed but there is still enough thickness left over for the later liftoff process.
- an insulation layer 414 such as silicon nitride, alumina, or silicon oxide, or silicon carbide is deposited with a thickness from 2 nm to 10 nm, covering the top and side walls of the PAC photoresist mask 412 , the top and side walls of the mask layer 436 , the side walls of the sensor 205 , and the exposed channel areas 432 and 434 .
- the insulation layer 414 can be deposited using IBD or PECVD method.
- a side-shield layer (or a hard bias layer) 440 is deposited on the insulation layer 414 , as shown in FIG. 4H .
- the side-shield or hard bias layer 440 may be a NiFe which can be deposited by sputtering method or a hard bias material that has a high magnetic moment such as CoFe.
- a liftoff process using hot NMP is performed to remove the PAC photoresist layer 412 and portions of the bias layer 440 covering the top and the sides of the PAC photoresist layer 412 , exposing the first mask layer 410 in the field area, as shown in FIG. 4I .
- the removal process leaves an uneven surface of the bias layer 440 , as shown in FIG. 4I .
- the uneven surface of the bias material 440 is then planarized by a CMP process.
- the resulting bias layer 440 is planar and has a surface 450 that is below the mask layers 410 , 436 , as shown in FIG. 4J .
- the mask layers 410 , 436 which are carbon based films, are subsequently removed by an oxygen based RIE process, exposing the cap layer 402 .
- the side-shield or hard bias layer 440 is not etched by the oxygen based plasma, the side-shield or the bias layer 440 now extends above the cap layer 402 .
- the portions of the side-shield or the hard bias layer 440 extending above the cap layer 402 are then removed by another CMP process, and the cap layer 402 serves as the CMP stop layer so that only the side-shield (the hard bias) layer 440 is removed.
- This second CMP process is controlled in such way that the remaining bias layer 440 and the cap layer 402 are planar, as shown in FIG. 4L .
- the cap layer 402 and a top portion of the side-shield (or hard bias) 440 which had been oxidized in the oxygen plasma are removed by an ion milling process, exposing the sensor structure 205 and the sensor layer 302 , as shown in FIG. 4M .
- the method of forming a sensor structure utilizing a hard mask stencil, as illustrated by FIGS. 4A-4M does not including utilizing a release layer. Instead, the method includes a two-step CMP process.
- a shallow and narrow hard mask stencil is utilized to form a sensor structure.
- the hard mask stencil includes four distinct layers.
- the hard mask stencil includes three layers of different materials and utilizes a two-step CMP process in the forming of the sensor structure.
Landscapes
- Engineering & Computer Science (AREA)
- Manufacturing & Machinery (AREA)
- Magnetic Heads (AREA)
Abstract
Description
- 1. Field
- Embodiments of the present invention generally relate to methods of making a magnetic read sensor. More particularly, embodiments of the present invention relate to methods of making a magnetic read sensor utilizing a super shallow laminated hard mask stencil.
- 2. Description of the Related Art
- The heart of a computer is a magnetic disk drive which typically includes a rotating magnetic disk, a slider that has read and write heads, a suspension arm above the rotating disk and an actuator arm that swings the suspension arm to place the read and/or write heads over selected circular tracks on the rotating disk. The suspension arm biases the slider towards the surface of the disk when the disk is not rotating but, when the disk rotates, air is swirled by the rotating disk and the adjacent air bearing surface (ABS) of the slider causes the slider to ride on an air bearing with a slight distance from the surface of the rotating disk. When the slider rides on the air bearing, the write and read heads are employed for writing magnetic impressions to and reading magnetic signals from the rotating disk. The read and write heads are connected to processing circuitry that operates according to a computer program to implement the writing and reading functions.
- To construct a read head, a plurality of sensor layers are deposited across the surface of a substrate. One or more mask layers are deposited over the sensor layers and a series of photolithographic processes and reactive ion etch (RIE) processes are then conducted to form a mask stencil above the sensor layers. An ion milling process then removes unmasked portions of the sensor layers to define the shape, profile and dimension (such as track width) of the read head sensor.
- In order to achieve greater data storage density on the magnetic media, magnetic data bits are written in increasingly smaller sizes. The read head is therefore fabricated with a reduced track width to properly read the smaller sized data bits. Therefore, there is a need in the art for an improved method for forming the narrow read head.
- The present invention generally relates to methods for forming a sensor structure utilizing a shallow and narrow hard mask stencil. In one embodiment, a sensor structure is formed by utilizing a four-layered hard mask stencil. The four-layered hard mask stencil includes a first mask layer, a second mask layer disposed over the first hard mask, a third mask layer disposed over the second mask layer, and a forth mask layer disposed over the third mask layer. In another embodiment, a sensor structure is formed by utilizing a three-layered hard mask stencil. The three-layered hard mask stencil includes a first mask layer, a second mask layer disposed over the first mask layer, and a third mask layer disposed over the second mask layer. The sensor structure is formed with a two-step chemical mechanical planarization (CMP) process.
- In one embodiment, a method for forming a read head is disclosed. The method includes forming a sensor layer on a substrate, forming a first mask layer over the sensor layer; forming a patterned bi-layer structure over a portion of the first mask layer, forming a RIE (reactive ion etch) stop layer over the first mask layer and the bi-layer structure, and removing the bi-layer structure and the portion of the RIE stop layer disposed over the bi-layer structure to expose a portion of the first mask layer. The area covered by the RIE stop layer is called the field area, and the area not covered by the RIE stop layer is called the device area.
- The method further includes forming a second mask layer over RIE stop layer (i.e., in the field area) and also over the exposed first mask layer (i.e., in the device area), forming a third mask layer over the second mask layer, forming a fourth mask layer over the third mask layer, forming a patterned photoresist mask in the device area using lithography process over the fourth mask layer, leaving portions of the device area and the entire field area exposed, then removing a portion of the fourth mask layer using a first RIE with certain amount of over-etch that the fourth mask layer is completely etched through in the area not protected by the photoresist mask and exposing portion of the third mask layer.
- The method further includes applying a second RIE process, which capable of selectively etch the photoresist mask, the third, the second and the first mask layer without (or with minimum) etch to the fourth mask layer and the RIE stop layer, forming a hard mask stencil (in the device area) consisting of four mask layers (i.e., the fourth, the third, the second, and the first mask layer) without photoresist residue disposed thereon. The device area is further divided into two areas, one is the stencil, another is channel area where the header sensor is not covered by the stencil and is exposed. The stencil is surrounded by the channel area. The third and second mask layer in the field area are also removed in the second RIE process, however the first mask layer in the field is not etched by the second RIE since the first mask layer is protected by the RIE stop layer.
- The method further includes forming a patterned photoresist mask on the RIE stop layer and leaving device area (including stencil and channel area) exposed. Thereafter an ion mill process is performed, the sensor layer in the channel area is etched away, the sensor layer under the stencil is protected by the stencil, and a reader sensor junction shape is formed under the stencil. The third mask layer of the stencil and partial of the second layer of the stencil are consumed during ion mill process, and the remaining of the second mask layer and first mask layer are still on the stencil. The RIE stop layer and the first mask layer in the field area is protected by the photoresist mask thus not etched by the ion mill, however, portions of the photomask are consumed in the ion mill.
- The method further includes forming an dielectric insulation layer (or layers) covering remaining stencil, channel areas and photoresist in field area, forming a hard bias layer on top of the dielectric layer, forming a cap layer on hard bias layer, removing the cap layer, the hard bias layer and the dielectric layer in the field area by a liftoff process to expose the RIE stop layer over the field area, removing the cap layer, the hard bias layer, the dielectric layer and the second mask layer of the stencil by a CMP process, exposing the first mask layer of the stencil, at the same time exposing the first mask layer in the field area, and partially removing the cap layer in the channel areas. A third RIE process is performed to remove the exposed first mask layer in both stencil and field area and the remaining cap layer in the channel areas, thus forming a reader junction sensor.
- In another embodiment, a method for forming a read head is disclosed. The method includes forming a sensor layer on a substrate, forming a cap layer over the sensor layer, forming a first mask layer having a first thickness over the cap layer, forming a second mask layer over the first mask layer, forming a third mask layer over the second mask layer, forming a patterned photoresist mask using lithography process over the third mask layer, leaving the rest of the device area exposed, removing a portion of the third mask layer not protected by the photoresist mask using a first reactive ion etch (RIE) with certain amount of over-etch that both the third layer and the second layer in the field area and in the channel area are completely etched through and exposing portion of the first mask layer in the field area and channel area. The first RIE process forms a stack in the device area consisting of residual photoresist, the third and the second mask layer, and part of the first layer. The stack is disposed on a remaining first mask layer having a second thickness.
- After forming the stack, a patterned photoresist mask is formed on the remaining first mask layer in the field area leaving the device area (i.e., the stack and the surrounding channel areas) exposed. The method further includes removing a portion of the remaining first mask layer in the channel areas using a second RIE process to etch away the remaining first mask layer in the channel areas, forming a hard mask stencil since the high etch selectivity of the third mask layer on the stencil, and leaving the photoresist mask in the field area partially etched with a remaining of thickness that is sufficient for the liftoff process later. Thereafter an ion mill process is performed to mill away the exposed sensor layer in the channel areas and a reader sensor junction shape is formed.
- The method further includes forming an dielectric insulation layer (or layers) covering the stencil, device area and photoresist in field area, forming a side-shield layer on top of the dielectric layer, removing the side-shield layer and the dielectric layer in the field area by a liftoff process to expose the first mask layer having a second thickness over the field area, removing the side-shield layer and dielectric layer and the second mask layer of the stencil by a first CMP process, and exposing the first mask layer of the stencil. The exposed first mask layer in the field has high CMP selectivity thus only partially removed. The method further includes removing the exposed first mask layer in field and the first mask layer on the stencil using a third RIE process to expose the cap layer in both stencil and filed area.
- The method further includes applying a second CMP to polish the portion of the side-shield. The cap layer has higher CMP selectivity that the bump-out side-shield is planarized and has the same flat surface with cap layer. Then an ion mill process with the same mill rate is used to remove the cap layer and portions of the side-shield, and a sensor junction is formed.
- 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 illustrates an exemplary magnetic disk drive, according to an embodiment of the invention. -
FIG. 2A is a side view of a read/write head and magnetic disk of the disk drive ofFIG. 1 , according to one embodiment of the invention. -
FIG. 2B is a schematic cross-sectional view of portions of the magnetic head according to one embodiment. -
FIGS. 3A-3P illustrate the process of making a sensor structure ofFIG. 2B according to one embodiment. -
FIGS. 4A-4M illustrate the process of making the sensor structure ofFIG. 2B according to another embodiment. - To facilitate understanding, identical reference numerals have been used, where possible, to designate identical elements that are common to the figures. It is contemplated that elements disclosed in one embodiment may be beneficially utilized on other embodiments without specific recitation.
- 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).
- The present invention generally relates to methods for forming a magnetic sensor structure utilizing a shallow and narrow hard mask stencil. In one embodiment, a sensor structure is formed by utilizing a four-layered hard mask stencil. The four-layered hard mask stencil includes a first mask layer, a second mask layer (a release layer), a third mask layer and a fourth mask layer. In another embodiment, a sensor structure is formed by utilizing a three-layered hard mask stencil. The three-layered hard mask stencil includes a first mask layer, a second mask layer, and a third mask layer. The sensor structure is formed with a two-step CMP process.
-
FIG. 1 illustrates a top view of anexemplary HDD 100, according to an embodiment of the invention. As illustrated,HDD 100 may include one or moremagnetic disks 110,actuator 120,actuator arms 130 associated with each of the magnetic disks, andspindle motor 140 affixed in achassis 150. The one or moremagnetic disks 110 may be arranged vertically as illustrated inFIG. 1 . Moreover, the one or more magnetic disks may be coupled with thespindle motor 140. -
Magnetic disks 110 may include circular tracks of data on both the top and bottom surfaces of the disk. Amagnetic head 180 mounted on a slider may be positioned on a track. As each disk spins, data may be written on and/or read from the data track.Magnetic head 180 may be coupled to anactuator arm 130 as illustrated inFIG. 1 .Actuator arm 130 may be configured to swivel aroundactuator axis 131 to placemagnetic head 180 on a particular data track. -
FIG. 2A is a fragmented, cross-sectional side view through the center of a read/write head 200 mounted on aslider 201 and facingmagnetic disk 202. The read/write head 200 and themagnetic disk 202 may correspond to themagnetic head 180 and themagnetic disk 110, respectively inFIG. 1 . In some embodiments, themagnetic 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 (PL) 206 formed on adisk substrate 208. The read/write head 200 includes an ABS, amagnetic write head 210 and amagnetic read head 211, and is mounted such that the ABS is facing themagnetic disk 202. InFIG. 2A , thedisk 202 moves past thewrite head 210 in the direction indicated by thearrow 232, so the portion ofslider 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 anMR sensing element 230 located between MR shields S1 and S2. In other embodiments, themagnetic read head 211 is a magnetic tunnel junction (MTJ) read head that includes aMTJ sensing device 230 located between MR shields S1 and S2. TheRL 204 is illustrated with perpendicularly recorded or magnetized regions, with adjacent regions having magnetization directions, as represented by the arrows located in theRL 204. The magnetic fields of the adjacent magnetized regions are detectable by the MR (or MTJ)sensing element 230 as the recorded bits. - The
write head 210 includes a magnetic circuit made up of amain pole 212 and ayoke 216. Thewrite head 210 also includes athin film coil 218 shown in the section embedded in anon-magnetic material 219 and wrapped aroundyoke 216. In an alternative embodiment, theyoke 216 may be omitted, and thecoil 218 may wrap around themain pole 212. Awrite pole 220 is magnetically connected to themain pole 212 and has anend 226 that defines part of the ABS of themagnetic write head 210 facing the outer surface ofdisk 202. -
Write pole 220 is a flared write pole and includes aflare point 222 and apole tip 224 that includes anend 226 that defines part of the ABS. The flare may extend the entire height of write pole 220 (i.e., from theend 226 of thewrite pole 220 to the top of the write pole 220), or may only extend from theflare point 222, as shown inFIG. 2A . In one embodiment the distance between theflare point 222 and the ABS is between about 0 nm and about 150 nm. - The
write pole 220 includes atapered surface 271 which increases a width of thewrite pole 220 from a first width W1 at the ABS to a second width W2 away from the ABS. In one embodiment, the width W1 may be between about 60 nm and 200 nm, and the width W2 may be between about 120 nm and 350 nm. While the taperedregion 271 is shown with a single straight surface inFIG. 2A , in alternative embodiment, the taperedregion 271 may include a plurality of tapered surface with different taper angles with respect to the ABS. - The tapering improves magnetic performance. For example, reducing the width W1 at the ABS may concentrate a magnetic field generated by the
write pole 220 over desirable portions of themagnetic disk 202. In other words, reducing the width W1 of thewrite pole 220 at the ABS reduces the probability that tracks adjacent to a desirable track are erroneously altered during writing operations. - While a small width of the
write pole 220 is desired at the ABS, it may be desirable to have a greater width of thewrite pole 220 in areas away from the ABS. A larger width W2 of thewrite pole 220 away from the ABS may desirably increase the magnetic flux to thewrite pole 220, by providing a greater thickness of thewrite pole 220 in a direction generally parallel to the ABS. In operation, write current passes throughcoil 218 and induces a magnetic field (shown by dashed line 228) from thewrite pole 220 that passes through the RL 204 (to magnetize the region of theRL 204 beneath the write pole 220), through the flux return path provided by thePL 206, and back to anupper return pole 250. In one embodiment, the greater the magnetic flux of thewrite pole 220, the greater is the probability of accurately writing to desirable regions of theRL 204. -
FIG. 2A further illustrates one embodiment of theupper return pole 250 that is separated fromwrite pole 220 by anonmagnetic gap layer 256. In some embodiments, theupper return pole 250 may be a trailing shield wherein substantially all of the shield material is on the trailingend 203. Alternatively, in some embodiments, theupper return pole 250 may be a wrap-around shield wherein the shield covers the trailingend 203 and also wraps around the sides of thewrite pole 220. AsFIG. 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 ashield gap throat 258. The throat gap width is generally defined as the distance between thewrite pole 220 and theupper return pole 250 at the ABS. Theupper return pole 250 is formed of magnetically permeable material (such as Ni, Co and Fe alloys) andgap layer 256 is formed of nonmagnetic material (such as Ta, TaO, Ru, Rh, NiCr, SiC or Al2O3). Ataper 260 in the gap material provides a gradual transition from the throat gap width at the ABS to a maximum gap width above thetaper 260. This gradual transition in width forms a tapered bump in the non-magnetic gap layer that allows for greater magnetic flux density from thewrite pole 220, while avoiding saturation of theupper return pole 250. - It should be understood that the
taper 260 may extend either more or less than is shown inFIG. 2A . The taper may extend upwards to an end of theupper return pole 250 opposite the ABS (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 the ABS to greater thicknesses at a first distance from the ABS, to a greatest thickness at a second distance (greater than the first distance) from the ABS. -
FIG. 2B is a schematic cross-sectional view of portions ofmagnetic head 211 according to one embodiment. The thickness and the width of each layer are for example only, and each layer may be thicker/thinner and/or wider/narrower. Themagnetic head 211 includes afirst shield layer 231. Thefirst shield layer 231 may comprise a ferromagnetic material. Suitable ferromagnetic materials that may be utilized include Ni, Fe, Co, NiFe, NiFeCo, NiCo, CoFe and combinations thereof. - The
magnetic head 211 also includes asensor structure 205 comprising a pinnedmagnetic layer 233, abarrier layer 234, afree layer 236 and anoptional capping layer 238. The pinnedmagnetic layer 233 may be one of several types of pinned layers, such as a simple pinned, antiparallel pinned, self pinned or antiferromagnetic pinned. For purposes of simplicity, the sensor will be described herein as antiparallel pinned. The antiferromagnetic pinned sensor has a first antiparallel pinned layer, a second antiparallel pinned layer, and a non-magnetic, antiferromagnetic coupling layer, such as Ru sandwiched between the two pinned layers. The first and second antiparallel pinned layers can be constructed of several magnetic materials, such as NiFe or CoFe, and have magnetic moments that are pinned by exchange coupling of the first antiparallel pinned layer with an antiferromagnetic layer. The antiferromagnetic layer may include materials such as PtMn, iridium, or rhodium. Thebarrier layer 234 may comprise an insulating material such as MgO or alumina. Thefree layer 236 may comprise ferromagnetic material such as Co, CoFe, CoFeB, NiFe or combinations thereof. Thecapping layer 238 may comprise a material to protect the sensor from damage such as ruthenium, iridium, tantalum or combinations thereof. - Following the formation of the sensor structure 205 (discussed in detail below), an insulating
layer 240 may be deposited on thefirst shield layer 231 as well as the sidewalls of thesensor structure 205. The insulatinglayer 240 may comprise an insulating material such as aluminum oxide, silicon nitride or silicon oxide. The insulatinglayer 240 may be deposited by well known deposition methods such as atomic layer deposition (ALD), chemical vapor deposition (CVD), sputtering, ion beam deposition (IBD) and etc. After the insulatinglayer 240 is deposited, a hard bias or a soft side-shield layer 242 is then deposited. The hard bias layer or soft side-shield 242 may comprise a material having a high magnetic moment such as CoFe or NiFe. - Once the hard bias layer or soft side-
shield 242 is deposited, acapping structure 244 may be formed. In one embodiment, thecapping structure 244 may comprise a multiple layer structure comprising a first tantalum layer, an iridium layer, and a second tantalum layer. After one or more planarization process, asecond shield layer 246 may be deposited over the cappingstructure 244 and thesensor structure 205. Thesecond shield layer 246 may comprise a ferromagnetic material. Suitable ferromagnetic materials that may be utilized include Ni, Fe, Co, NiFe, NiFeCo, NiCo, CoFe and combinations thereof. - In order to form the
sensor structure 205, a hard mask stencil is formed over thelayers sensor structure 205. Typically a conventional mask stencil has a height of about 100 nanometers (nm) and a width of about 30 to 40 nm. As thesensor structure 205 gets narrower, a shallower and narrower hard mask stencil with better control on both track width and height within wafer and wafer to wafer should be utilized.FIGS. 3A-3P illustrate the process of making thesensor structure 205 utilizing such shallow and narrow hard mask stencil. - As
FIG. 3A illustrates, thesensor layer 302 is deposited over thefirst shield layer 231. Thesensor layer 302 may include the pinnedmagnetic layer 233, thebarrier layer 234, thefree layer 236 and theoptional capping layer 238. Afirst mask layer 304 is deposited over thesensor layer 302. Thefirst mask layer 304 may be a diamond-like carbon (DLC) layer that is deposited by plasma enhanced chemical vapor deposition (PECVD), ion beam deposition (IBD), or any other suitable deposition process. In one embodiment, thefirst mask layer 304 is deposited by IBD and has a thickness of about 3 nm to about 8 nm. One of the functions of thefirst mask layer 304 is to serve as a CMP stop layer as discussed below. InFIG. 3B , abi-layer structure 306 is deposited over thefirst mask layer 304. Thebi-layer structure 306 includes arelease layer 308 and aphotoresist layer 310. Therelease layer 308 may be polydimethylglutarimide (PMGI) and thephotoresist layer 310 may be a polyphenolic polymer or polyvinylphenol. Gaps (or undercuts) 307 and 309 are formed between thephotoresist layer 310 and thefirst mask layer 304 at the bottom of thebi-layer structure 306. During the photolithography process there ismore release layer 308 being removed and the recessed sides of therelease layer 308 causes undercuts 307 and 309 below thephotoresist layer 310. - As shown in
FIG. 3C , an RIE stop layer 312 (as will be discussed in detail later) is deposited over the uncovered portions of the firsthard mask layer 304 and thephotoresist layer 310. TheRIE stop layer 312 also covers the side walls of thephotoresist layer 310; however, theundercuts RIE stop layer 312 because of thegap RIE stop layer 312 may be silicon nitride (SiN), tantalum oxides (TaO, Ta2O3, Ta2O5), silicon carbide (SiC), silicon dioxide (SiO2), silicon oxynitride (SiOxNy), or other suitable material. In one embodiment, theRIE stop layer 312 is SiN having a thickness of about 2 nm to 8 nm and is deposited by ALD, PECVD, IBD, or sputtering method. Next, thebi-layer structure 306 is subjected to a photoresist stripper for dissolving therelease layer 308 and releasing thephotoresist layer 310 from thefirst mask layer 304. The photoresist stripper dissolves therelease layer 308 andphotoresist layer 310 by entering into theundercuts release layer 308 and thephotoresist layer 310 is N-methyl pyrrolidone (NMP). As shown inFIG. 3D , after the removing of thebi-layer structure 306, theRIE stop layer 312 covers portions of thefirst mask layer 304, and the portions are called the field area. The exposed portion of thefirst mask layer 304 not covered by theRIE stop layer 312 is called the device area. - Next, as shown in
FIG. 3E , asecond mask layer 314 is deposited on the exposed first hard mask layer 304 (device area) and on the RIE stop layer 312 (field area). In one embodiment, thesecond mask layer 314 is a polymer-like carbon (PLC), which is much softer than DLC of thefirst mask layer 304, and has a thickness of about 5 nm to about 10 nm over thefirst mask layer 304 and can be deposited by either PECVD or IBD method. Thesecond mask layer 314 serves as a release layer in the CMP process as discussed below in detail. Athird mask layer 316 is deposited over thesecond mask layer 314, as shown inFIG. 3F . In one embodiment, thethird mask layer 316 is a material that has a low milling rate, such as C or DLC and has a thickness of about 5 nm to about 10 nm. Thethird mask layer 316 may be deposited by any suitable process, such as IBD, PECVD or sputtering. - In
FIG. 3G , afourth mask layer 318 is deposited over thethird mask layer 316. Thefourth mask layer 318 may be a dielectric film or a thin metal layer. In one embodiment, thefourth mask layer 318 is a dielectric hard mask layer. The dielectrichard mask layer 318 may be constructed of a dielectric material and is preferably constructed of a silicon-containing hard mask material such as silicon oxide, silicon nitride, silicon oxynitride which may be deposited using PECVD, IBD or sputtering method, or a silicon-containing organic material such as SIHM® (Shin-Etsu Chemical Co., Ltd.) or UVAS (Honeywell International Inc.) and etc, which may be spin-coated on and cured at elevated temperature from 150 degrees Celsius to 250 degrees Celsius. In various approaches, the thickness of the dielectrichard mask layer 318 may depend on the total thickness of thefirst mask layer 304, thesecond mask layer 314 and thethird mask layer 316. Generally, the thicker the total thickness of 304, 314 and 316, the thicker the dielectrichard mask layer 318 will preferably be. The typical thickness of the silicon containing dielectrichard mask layer 318 is about 5 nm to about 30 nm. - In one embodiment, an optional bottom anti-reflective coating (BARC) may be deposited over the dielectric
hard mask layer 318. The determination of whether a BARC layer is desirable depends on the requirements of the photolithograph and on the material used for the dielectrichard mask layer 318. For example, if the dielectrichard mask layer 318 is a material that acts as a BARC, then no BARC layer is deposited. Such materials include silicon oxynitride, SIHM® (Shin-Etsu Chemical Co., Ltd.), UVAS (Honeywell International Inc.), and etc. In other cases, some form of BARC is desirable to control photolithography parameters such as reflective swing and photo CDs, and a BARC layer is deposited by any suitable deposition method such as spin coating and then baking. For simplicity, hereafter the dielectrichard mask layer 318 represents both the mask layer and the BARC layer if any. - Next in
FIG. 3H , aphotoresist layer 352 is deposited over the dielectrichard mask layer 318. A photolithography process is then performed to form a photoresist mask in which only a small portion of thephotoresist layer 352 remains on the dielectrichard mask layer 318 in the device area, as shown inFIG. 3H , and the remaining portion of the dielectrichard mask layer 318 is exposed. - Next, a first RIE process is performed to remove portions of the dielectric
hard mask layer 318 that are not protected by thephotoresist mask 352, as shown inFIG. 3I . The RIE may use fluorocarbon based gas chemistry mixed with other gases as etchants to perform the etching. In one approach, this RIE may preferably be performed in a fluorine containing plasma chemistry such as one that contains CF4, CHF3, Ar, He, O2 and etc., a combination thereof, or any other compound which would be apparent to one skilled in the art upon reading the present description. It is preferable that both CF4 and CHF3 gas flows are in the range of 5 sccm to 50 sccm, the He gas flow is no more than 30 sccm, and the oxygen gas flow is between 1 sccm to 10 sccm. According to an illustrative approach, the first RIE may additionally include transferring the image of thephotoresist mask 352 onto the under-lying dielectrichard mask layer 318 by removing portions of the dielectrichard mask layer 318 that are not protected by thephotoresist mask 352, leaving a structure as shown inFIG. 3I . - While any suitable tool known in the art may be used, one plasma tool especially suitable for the RIE process to etch the dielectric hard mask material and polymer mask under-layer is Plasma-Therm's VERSALOCK® etcher, which is an inductively coupled plasma (ICP) etch system in which the plasma is generated by means of inductively coupling 2 MHz RF power (the source power) while independently controlling the ion energy directed toward the substrate via 13.56 MHz bias power. This separate power control allows a wider range of RIE processes to be performed, ranging from highly chemical processes to highly physical processes. The VERSALOCK® etcher is equipped with an Optical Emission Spectrometry (OES) endpoint system that allows precise control of the over-etch amount via the determination of etch endpoint.
- Many other ICP etchers equipped with both source and bias power supplies, such as TCP9400DFM® from Lam Research Inc., or DPS® from Applied Materials Inc., can also be used for RIE the dielectric hard mask material and polymer mask under-layer. It is expected that the RIE process presented herein can be used in conjunction with many different ICP etchers.
- In the first RIE process, to ensure all of the dielectric
hard mask 318 in the area not protected by thephotoresist 352 is completely removed, or thethird mask layer 316 is completely exposed in the area not protected by thephotoresist mask 352, a certain amount of over-etch is applied, the percentage of the over etch time can be ranging from 20% to 60%. At the end of the first RIE process, the pattern of thephotoresist mask layer 352 is transferred onto the dielectrichard mask layer 318, and part of thephotoresist mask 352 is consumed during the first RIE. - Referring to
FIG. 3J , the image of the dielectrichard mask 318 may be transferred onto the layer disposed thereunder (i.e., layers 316, 314 and 304) using a second RIE which may have a different material selectivity than the first RIE, to form a stencil consisting oflayers photoresist layer 352 remaining from the first RIE (and optional BARC layer if any) is etched away completely during the second RIE. Since the dielectrichard mask layer 318 has much slower etch rate (or high etch rate selectivity), only a small portion of the dielectrichard mask 318 is consumed, thus the mask pattern of the dielectrichard mask layer 318 is transferred to thethird mask layer 316, thesecond mask layer 314 and thefirst mask layer 304, the portion of these three layers which are not protected by the dielectrichard mask layer 318 are etched away in the device area, and the remaining layers in the device area form ahard mask stencil 320. In addition, since thecap layer 312 is a kind of dielectric layer and also has high etch selectivity (i.e., it doesn't etch by oxygen based plasma), the second RIE stops on thecap layer 312 in the field area, thus thefirst mask layer 304 under thecap layer 312 is not etched, as shown inFIG. 3J . As a result of the two RIE processes, thehard mask stencil 320 is formed in the device area, as shown inFIG. 3J . Portions of thesensor layer 302 are exposed while the remaining portions of thesensor layer 302 are covered by the hard mask stencil 320 (in device area) and the first mask layer 304 (in field area). The resultinghard mask stencil 320 includes four layers and has a height (thickness) between about 30 nm and about 65 nm and a width between about 10 nm to about 30 nm. In one embodiment, thehard mask stencil 320 has a height of about 45 nm. Thehard mask stencil 320 provides better wafer to wafer and within wafer control on mill stencil CD uniformity and height by combining both low RIE and low milling etch rate mask layers. The reduced height of thehard mask stencil 320 helps with symmetric junction shape formation and the narrow width of thehard mask stencil 320 helps with narrow track width read sensor fabrication. - To assist the liftoff process discussed below, a
photoresist mask layer 330 is fabricated. The field area which is protected by thecap layer 312 is completely covered by thephotoresist 330, and the device area (including the stencil 320) is exposed and has no photoresist over it at all, as shown inFIG. 3K . The thickness of thephotoresist 330 is about 150 nm to 300 nm. After the formation ofphotoresist mask 330, an ion milling process with desired angle, time, strength and operation mode is performed to remove portions of thesensor layer 302 that are not protected by thehard mask stencil 320 and thephotoresist mask 330. As a result of the ions milling through thesensor layer 302 and exposing thefirst shielding layer 231,channels sensor layer 302, and a taperedreader sensor stack 205 is formed under thestencil 320, as shown inFIG. 3L . During the ion milling, the entirefourth mask layer 318 and a portion of thethird mask layer 316 of thehard mask stencil 320 are consumed as a result of the ion milling process, and portions of thephotoresist mask 330 are also removed in the ion mill. Thus the thickness of thephotoresist mask 330 is reduced but still sufficient enough for liftoff process as discussed below. The remaining thickness of thephotoresist mask layer 330 is about 50 nm to about 200 nm. - After the formation of
sensor stack 205, as shown inFIG. 3M , aninsulation dielectric layer 338 is first deposited as an insulation layer, followed by a magnetic hard bias (or soft side-shield)material 340 deposition into thechannels photoresist layer 330 and the top of thehard mask stencil 320. Theinsulation layer 338 and the hard bias (or soft side-shield)material 340 also cover side walls of thestencil 320, side walls ofsensor 205 and side walls ofphotoresist mask 330. The suitable materials for the insulation layer can be various dielectric films such as silicon nitride, alumina, silicon oxide, tantulum oxide, silicon carbride, with thickness from about 2 nm to about 10 nm, and can be deposited by sputtering, PECVD or IBD method. The hard bias (or soft side-shield)material 340 may be a material that has a high magnetic moment such as CoFe or NiFe which can be deposited by sputtering method. - Another
optional layer 360 may be deposited over the hard bias (or soft side-shield)material 340. Theoptional layer 360 may be diamond-like carbon, and has a thickness of about 2 nm to about 10 nm. As shown inFIG. 3N , thephotoresist mask 330 along with theoptional layer 360, the hard bias (or soft side-shield)material 340, and theinsulation layer 338 covering the top and the side of thephotoresist mask 330 may be removed. The removal may be achieved by first baking the structure at elevated temperature such as about 90 degrees Celsius to about 180 degrees Celsius and then cooling the structure rapidly, followed by one or more rounds of hot NMP liftoff. During heating and cooling, cracks are formed on theoptional layer 360, the hard bias (or soft side-shield)material 340 andinsulation layer 338, thus allowing the hot NMP at temperature from about 60 degrees Celsius to about 90 degrees Celsius to reach the coveredphotoresist mask 330 to liftoff thephotoresist mask 330 and everything on thephotoresist mask 330 in the field area. After the liftoff, theRIE stop layer 312 and thefirst mask layer 304 are remaining in the field area. Thesensor 205,stencil 320,insulation layer 338, hard bias layer (or soft side-shield) 340 andoptional layer 360 are still remaining in the device area. - Following the liftoff of
photoresist mask 330, a CMP process is performed. In the field area, the CMP process removes theRIE stop layer 312 and stops on thefirst mask layer 304 since the dielectric material of theRIE stop layer 312 can be polished much faster than the DLC material of thefirst mask layer 304. In thechannels optional layer 360 since theoptional layer 360 is DLC material, thus protects the hard bias (or soft side-shield)material 340. On thestencil 320, since thesecond mask layer 314 is a polymer like carbon which is much soft than the DLC material of thefirst mask layer 304, when a CPM process is applied, the stencil breaks at the interface between thesecond mask layer 314 and thefirst mask layer 304. Anything on thestencil 320 above thefirst mask layer 304 is removed. As a result of this CMP process, the exposed surface in thechannels optional layer 360, the exposed surface of the stencil comprises thefirst mask layer 304, and the exposed surface in the field also comprises thefirst mask layer 304, as illustrated inFIG. 3O . The above discussed removal process is achieved by a CMP process and thus is called CMP assisted liftoff. The resulting planar surface includes the first mask layer 304 (in both field area and on the sensor) and theoptional layer 360. - After the CMP assisted liftoff, the remaining DLC film of the
first mask layer 304 and theoptional layer 360 are removed by an oxygen based RIE process, exposing the cap layer of thesensor structure 205 in device area, the hard bias (or soft side-shield)layer 340 and thesensor layer 302 in the field area. The top magnetic shield layer composed with NiFe is then deposited with sputtering method or metal plating method, and more subsequent processes are performed to fabricate a magnetic recording sensor. -
FIGS. 3A-3P illustrate one manner of making a sensor structure utilizing a shallow and narrow hard mask stencil.FIGS. 4A-4M illustrate an alternative way of making the sensor structure utilizing a different shallow and narrow hard mask stencil. As shown inFIG. 4A , thesensor layer 302 is deposited over thefirst shield layer 231. Acap layer 402 is deposited over thesensor layer 302, and afirst mask layer 404 is deposited over thecap layer 402. In one embodiment, thecap layer 402 is iridium (Ir) and has a thickness of about 2 nm to about 6 nm and can be deposited using sputtering method. However, other suitable materials may also be used, such as ruthenium (Ru) with similar thickness. Thefirst mask layer 404 may be a diamond-like carbon layer having a thickness between about 10 nm and about 50 nm and can be deposited using either PECVD or IBD process. - As shown in
FIGS. 4B and 4C , asecond mask layer 406 is deposited over thefirst mask layer 404 and athird mask layer 408 is deposited over thesecond mask layer 406. In one embodiment, thesecond mask layer 406 is a dielectric material such as silicon oxide and has a thickness of about 5 nm to about 20 nm. However, other suitable dielectric materials may also be used, such as silicon, silicon nitride, silicon carbide, silicon oxynitride or tantalum oxide. Thedielectric material 406 can be deposited using PECVD, IBD or sputtering method. Thethird mask layer 408 may be a regular non-silicon based BARC layer or a silicon based BARC layer such as SIHM® (Shin-Etsu Chemical Co., Ltd.), UVAS (Honeywell International Inc.) and etc., with a thickness ranging from about 20 nm to 60 nm. A photoresist layer is coated and baked over thethird mask layer 408, a photolithography process is performed, and aphotoresist mask 409 is formed on thethird mask layer 408, exposing portions of the third mask layer, as shown inFIG. 4C . - Next in
FIG. 4D , a first RIE process containing fluorocarbon such as CF4/CHF3 mixed with other gases such as oxygen, argon and helium is performed. Portions of thethird mask layer 408 not protected by thephotoresist mask 409 is etched away, and with continuing of the RIE, a portion of thesecond mask layer 406 and a portion of thefirst mask layer 404 not protected by thephotoresist mask 409 are also removed. Although thethird mask layer 408 and thesecond mask layer 406 are etched through in the area not protected by thephotoresist mask 409, the first mask layer is not etched through. The RIE process stops on thefirst mask layer 404, and the etch depth of thefirst mask layer 404 depends on the total over etch amount of the third and second mask layers 408, 406. A portion of thephotoresist mask 409 is consumed in the first RIE and the thickness is reduced. As the result of the first RIE, the remainingphotoresist mask 409, thethird mask 408, thesecond mask layer 406, and a portion of thefirst mask layer 404 form astack 411. A portion of thefirst mask layer 404 having the entire width “W” and depth “D” is not affected by this first RIE and is labeled with 410. Thus, thestack 411 sits on amask layer 410 that has a thickness less than thefirst mask layer 404. In one embodiment, the thickness of themask layer 410 is half of thefirst mask layer 404. The remainingphotoresist layer 409 may or may not be removed by a wet strip process depending on the needs. - A photoresist layer is then coated and baked, and a photolithography is performed to form a photoresist assisted CMP (PAC)
photoresist mask 412 on thefirst mask layer 410, as shown inFIG. 4E . Thephotoresist mask 412 covers only the field area, leaving thestack 411 and surrounding area (i.e., channel areas formed in the ion mill as discussed later) exposed. The channel areas (i.e., the portions of themask layer 410 neither protected by thephotoresist layer 412 nor the stack 411) is removed by a second RIE process based on the oxygen plasma chemistry, exposing thecap layer 402 in the channel areas. Since thePAC photoresist mask 412 is applied with enough thickness that there is sufficient remainingPAC photoresist mask 412 leftover in the field area. The remainingphotoresist mask 409 is completely removed in the second RIE process, and the second RIE is stopped on thethird mask layer 408 if thethird mask layer 408 is a silicon based BARC material such as SIHM® (Shin-Etsu Chemical Co., Ltd.), UVAS (Honeywell International Inc.), which has high etch selectivity so only a small amount of the top portion is etched away. If thethird mask layer 408 is a regular non-silicon based BARC layer, thethird mask layer 408 is completely removed in the second RIE process, and since thesecond mask layer 406 is a dielectric based mask layer, the second RIE will not etch thesecond mask layer 406, protecting theunderneath mask layer 404 from being etched. Ahard mask stencil 420, consisting of thethird mask layer 408, thesecond mask layer 406 and thefirst mask layer 404, is formed, as shown inFIG. 4F . Thehard mask stencil 420 has a width between about 10 nm and about 30 nm and a height between about 20 nm and about 60 nm. In one embodiment, thehard mask stencil 420 has a height of about 40 nm. - To form the sensor structure, an ion milling is performed to remove portions of the
cap layer 402 and thesensor layer 302 not protected by thephotoresist layer 412 and thehard mask stencil 420.Channels sensor layer 302 are formed and portions of thefirst shield layer 231 are exposed, as shown inFIG. 4G . In addition, thethird mask layer 408, thesecond mask layer 406, and a portion of thefirst mask layer 404 of thehard mask stencil 420 are also consumed as a result of the ion milling process. Thus, disposed above thesensor structure 205 is amask layer 436, which is the remaining portion of thefirst mask layer 404 and thecap layer 402. Portion of thephotoresist mask layer 412 is also consumed but there is still enough thickness left over for the later liftoff process. - Next, an
insulation layer 414 such as silicon nitride, alumina, or silicon oxide, or silicon carbide is deposited with a thickness from 2 nm to 10 nm, covering the top and side walls of thePAC photoresist mask 412, the top and side walls of themask layer 436, the side walls of thesensor 205, and the exposedchannel areas insulation layer 414 can be deposited using IBD or PECVD method. Then a side-shield layer (or a hard bias layer) 440 is deposited on theinsulation layer 414, as shown inFIG. 4H . The side-shield orhard bias layer 440 may be a NiFe which can be deposited by sputtering method or a hard bias material that has a high magnetic moment such as CoFe. - A liftoff process using hot NMP is performed to remove the
PAC photoresist layer 412 and portions of thebias layer 440 covering the top and the sides of thePAC photoresist layer 412, exposing thefirst mask layer 410 in the field area, as shown inFIG. 4I . The removal process leaves an uneven surface of thebias layer 440, as shown inFIG. 4I . The uneven surface of thebias material 440 is then planarized by a CMP process. The resultingbias layer 440 is planar and has asurface 450 that is below the mask layers 410, 436, as shown inFIG. 4J . The mask layers 410, 436, which are carbon based films, are subsequently removed by an oxygen based RIE process, exposing thecap layer 402. As shown inFIG. 4K , since the side-shield orhard bias layer 440 is not etched by the oxygen based plasma, the side-shield or thebias layer 440 now extends above thecap layer 402. The portions of the side-shield or thehard bias layer 440 extending above thecap layer 402 are then removed by another CMP process, and thecap layer 402 serves as the CMP stop layer so that only the side-shield (the hard bias)layer 440 is removed. This second CMP process is controlled in such way that the remainingbias layer 440 and thecap layer 402 are planar, as shown inFIG. 4L . Lastly, thecap layer 402 and a top portion of the side-shield (or hard bias) 440 which had been oxidized in the oxygen plasma are removed by an ion milling process, exposing thesensor structure 205 and thesensor layer 302, as shown inFIG. 4M . The method of forming a sensor structure utilizing a hard mask stencil, as illustrated byFIGS. 4A-4M , does not including utilizing a release layer. Instead, the method includes a two-step CMP process. - In summary, a shallow and narrow hard mask stencil is utilized to form a sensor structure. In one embodiment, the hard mask stencil includes four distinct layers. In another embodiment, the hard mask stencil includes three layers of different materials and utilizes a two-step CMP process in the forming of the sensor structure.
- 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.
Claims (24)
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US13/907,617 US8889019B1 (en) | 2013-05-31 | 2013-05-31 | Super shallow laminated hard mask stencil for magnetic read sensor fabrication |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US13/907,617 US8889019B1 (en) | 2013-05-31 | 2013-05-31 | Super shallow laminated hard mask stencil for magnetic read sensor fabrication |
Publications (2)
Publication Number | Publication Date |
---|---|
US8889019B1 US8889019B1 (en) | 2014-11-18 |
US20140353276A1 true US20140353276A1 (en) | 2014-12-04 |
Family
ID=51870083
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US13/907,617 Active 2033-07-03 US8889019B1 (en) | 2013-05-31 | 2013-05-31 | Super shallow laminated hard mask stencil for magnetic read sensor fabrication |
Country Status (1)
Country | Link |
---|---|
US (1) | US8889019B1 (en) |
Cited By (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US9595273B1 (en) | 2015-09-30 | 2017-03-14 | Western Digital (Fremont), Llc | Shingle magnetic writer having nonconformal shields |
CN106929800A (en) * | 2017-04-24 | 2017-07-07 | 信利光电股份有限公司 | A kind of diamond-like carbon composite film and preparation method thereof |
Families Citing this family (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US9513349B2 (en) * | 2014-02-06 | 2016-12-06 | HGST Netherlands B.V. | Scissor type magnetic sensor with high magnetic moment bias structure for reduced signal asymmetry |
Citations (11)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US20050041341A1 (en) * | 2002-11-29 | 2005-02-24 | Marie-Claire Cyrille | CMP assisted liftoff micropatterning |
US20120125884A1 (en) * | 2010-11-24 | 2012-05-24 | Hitachi Global Storage Technologies Netherlands B. V. | Method for manufacturing a narrow magnetic read width current perpendicular to plane magnetoresistive sensor |
US20120125883A1 (en) * | 2010-11-23 | 2012-05-24 | Hitachi Global Storage Technologies Netherlands B.V. | Method for manufacturing a magnetic write pole using a multi-layered hard mask structure |
US20120156390A1 (en) * | 2010-12-21 | 2012-06-21 | Hitachi Global Storage Technologies Netherlands B.V. | Multi-angle hard bias deposition for optimal hard-bias deposition in a magnetic sensor |
US8296930B2 (en) * | 2009-12-22 | 2012-10-30 | Hitachi Global Storage Technologies Netherlands B.V. | Method for manufacturing a magnetoresistive sensor having a flat shield |
US20130082027A1 (en) * | 2011-09-30 | 2013-04-04 | Hitachi Global Storage Technologies Netherlands B.V. | Method for manufacturing a perpendicular magnetic write head using novel reactive ion etching chemistry |
US20130081263A1 (en) * | 2011-09-30 | 2013-04-04 | Hitachi Global Storage Technologies Netherlands B.V. | Method for manufacturing a magnetic write pole of a perpendicular magnetic write head using novel mask fabrication |
US20130104388A1 (en) * | 2011-10-31 | 2013-05-02 | Guomin Mao | Novel high bevel angle magnetic writer pole fabrication process |
US20130284693A1 (en) * | 2012-04-27 | 2013-10-31 | Hitachi Global Storage Technologies Netherlands B.V. | Differentiated liftoff process for ultra-shallow mask defined narrow trackwidth magnetic sensor |
US20140144872A1 (en) * | 2012-11-28 | 2014-05-29 | HGST Netherlands B.V. | Method for manufacturing a magnetic write head using novel mask structure |
US20140170774A1 (en) * | 2012-12-13 | 2014-06-19 | HGST Netherlands B.V. | Method for manufacturing a magnetoresistive sensor |
Family Cites Families (9)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US6700759B1 (en) | 2000-06-02 | 2004-03-02 | Western Digital (Fremont), Inc. | Narrow track width magnetoresistive sensor and method of making |
US6861177B2 (en) | 2002-02-21 | 2005-03-01 | Hitachi Global Storage Technologies Netherlands B.V. | Method of forming a read sensor using a lift-off mask having a hardmask layer and a release layer |
US7378226B2 (en) | 2004-04-20 | 2008-05-27 | Headway Technologies, Inc. | Ozone-assisted bi-layer lift-off stencil for narrow track CPP-GMR heads |
US7037847B2 (en) | 2004-05-28 | 2006-05-02 | Hitachi Global Storage Technologies Netherlands, B.V. | Methods for fabricating read sensor for magnetic heads with reduced read track width |
US20060158790A1 (en) | 2005-01-14 | 2006-07-20 | Hitachi Global Storage Technologies | Magnetoresistive sensor having a novel junction structure for improved track width definition and pinned layer stability |
US20060273066A1 (en) | 2005-06-01 | 2006-12-07 | Hitachi Global Storage Technologies | Method for manufacturing a magnetic sensor having an ultra-narrow track width |
US8252516B2 (en) | 2008-10-30 | 2012-08-28 | HGST Netherlands, B.V. | Manufacturing a narrow track read head |
US20110089140A1 (en) | 2009-10-16 | 2011-04-21 | Liubo Hong | Process for fabricating ultra-narrow track width magnetic sensor |
US8216481B2 (en) | 2009-10-16 | 2012-07-10 | Hitachi Global Storage Technologies Netherlands B.V. | Process for fabricating ultra-narrow dimension magnetic sensor |
-
2013
- 2013-05-31 US US13/907,617 patent/US8889019B1/en active Active
Patent Citations (16)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US6969625B2 (en) * | 2002-11-29 | 2005-11-29 | International Business Machines Corporation | CMP assisted liftoff micropatterning |
US20050041341A1 (en) * | 2002-11-29 | 2005-02-24 | Marie-Claire Cyrille | CMP assisted liftoff micropatterning |
US8296930B2 (en) * | 2009-12-22 | 2012-10-30 | Hitachi Global Storage Technologies Netherlands B.V. | Method for manufacturing a magnetoresistive sensor having a flat shield |
US20120125883A1 (en) * | 2010-11-23 | 2012-05-24 | Hitachi Global Storage Technologies Netherlands B.V. | Method for manufacturing a magnetic write pole using a multi-layered hard mask structure |
US20120125884A1 (en) * | 2010-11-24 | 2012-05-24 | Hitachi Global Storage Technologies Netherlands B. V. | Method for manufacturing a narrow magnetic read width current perpendicular to plane magnetoresistive sensor |
US20120156390A1 (en) * | 2010-12-21 | 2012-06-21 | Hitachi Global Storage Technologies Netherlands B.V. | Multi-angle hard bias deposition for optimal hard-bias deposition in a magnetic sensor |
US8646168B2 (en) * | 2011-09-30 | 2014-02-11 | HGST Netherlands B.V. | Method for manufacturing a magnetic write pole of a perpendicular magnetic write head using novel mask fabrication |
US20130082027A1 (en) * | 2011-09-30 | 2013-04-04 | Hitachi Global Storage Technologies Netherlands B.V. | Method for manufacturing a perpendicular magnetic write head using novel reactive ion etching chemistry |
US20130081263A1 (en) * | 2011-09-30 | 2013-04-04 | Hitachi Global Storage Technologies Netherlands B.V. | Method for manufacturing a magnetic write pole of a perpendicular magnetic write head using novel mask fabrication |
US20130104388A1 (en) * | 2011-10-31 | 2013-05-02 | Guomin Mao | Novel high bevel angle magnetic writer pole fabrication process |
US8468683B2 (en) * | 2011-10-31 | 2013-06-25 | HGST Netherlands B.V. | High bevel angle magnetic writer pole fabrication process |
US20130284693A1 (en) * | 2012-04-27 | 2013-10-31 | Hitachi Global Storage Technologies Netherlands B.V. | Differentiated liftoff process for ultra-shallow mask defined narrow trackwidth magnetic sensor |
US20140144872A1 (en) * | 2012-11-28 | 2014-05-29 | HGST Netherlands B.V. | Method for manufacturing a magnetic write head using novel mask structure |
US8801944B2 (en) * | 2012-11-28 | 2014-08-12 | HGST Netherlands B.V. | Method for manufacturing a magnetic write head using novel mask structure |
US20140170774A1 (en) * | 2012-12-13 | 2014-06-19 | HGST Netherlands B.V. | Method for manufacturing a magnetoresistive sensor |
US8796152B2 (en) * | 2012-12-13 | 2014-08-05 | HGST Netherlands B.V. | Method for manufacturing a magnetoresistive sensor |
Cited By (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US9595273B1 (en) | 2015-09-30 | 2017-03-14 | Western Digital (Fremont), Llc | Shingle magnetic writer having nonconformal shields |
CN106929800A (en) * | 2017-04-24 | 2017-07-07 | 信利光电股份有限公司 | A kind of diamond-like carbon composite film and preparation method thereof |
Also Published As
Publication number | Publication date |
---|---|
US8889019B1 (en) | 2014-11-18 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
US7715147B2 (en) | Magnetic write head having a shield that extends below the leading edge of the write pole | |
US8617408B2 (en) | Method for manufacturing a magnetic read sensor with narrow track width using amorphous carbon as a hard mask and localized CMP | |
US8721902B1 (en) | Method and system for providing an energy assisted magnetic recording writer having a heat sink and NFT | |
US8828248B2 (en) | Method for defect reduction in magnetic write head fabrication | |
US8836059B2 (en) | Shape enhanced pin read head magnetic transducer with stripe height defined first and method of making same | |
US9230576B1 (en) | Scissor reader with side shield decoupled from bias material | |
US9082435B1 (en) | Fabrication of multiple sensor layers with self-aligned back edge | |
US7506431B2 (en) | Method of manufacturing a perpendicular magnetic write head having a wrap-around trailing shield and a concave trailing edge main pole | |
US8137570B2 (en) | Additive write pole process for wrap around shield | |
US8796152B2 (en) | Method for manufacturing a magnetoresistive sensor | |
US8468683B2 (en) | High bevel angle magnetic writer pole fabrication process | |
JP2006209944A (en) | Method for controlling mask profile for forming reading sensor | |
US9449635B2 (en) | Method for forming a magnetic head for perpendicular magnetic recording | |
US20120187079A1 (en) | Method for manufacturing a magnetic sensor having a flat upper shield | |
US20090184091A1 (en) | Diamond-like carbon (dlc) hardmask and methods of fabrication using same | |
US8475670B2 (en) | Method for manufacturing a patterned magnetic media with offset data and servo regions | |
US8889019B1 (en) | Super shallow laminated hard mask stencil for magnetic read sensor fabrication | |
US9177588B2 (en) | Recessed IRMN reader process | |
US8636913B2 (en) | Removing residues in magnetic head fabrication | |
US20110089140A1 (en) | Process for fabricating ultra-narrow track width magnetic sensor | |
US20120125884A1 (en) | Method for manufacturing a narrow magnetic read width current perpendicular to plane magnetoresistive sensor | |
US20060273066A1 (en) | Method for manufacturing a magnetic sensor having an ultra-narrow track width | |
US8839504B2 (en) | Method of fabricating a device having a sidegap | |
JP2004355669A (en) | Magnetic recording head and its manufacturing method | |
US20130082027A1 (en) | Method for manufacturing a perpendicular magnetic write head using novel reactive ion etching chemistry |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
AS | Assignment |
Owner name: HGST NETHERLANDS B.V., NETHERLANDS Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNORS:MAO, GUOMIN;SOUGRATI, HICHAM MOULAY;ZHENG, YI;SIGNING DATES FROM 20130528 TO 20130529;REEL/FRAME:030527/0832 |
|
FEPP | Fee payment procedure |
Free format text: PAYOR NUMBER ASSIGNED (ORIGINAL EVENT CODE: ASPN); ENTITY STATUS OF PATENT OWNER: LARGE ENTITY |
|
STCF | Information on status: patent grant |
Free format text: PATENTED CASE |
|
AS | Assignment |
Owner name: WESTERN DIGITAL TECHNOLOGIES, INC., CALIFORNIA Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNOR:HGST NETHERLANDS B.V.;REEL/FRAME:040829/0516 Effective date: 20160831 |
|
MAFP | Maintenance fee payment |
Free format text: PAYMENT OF MAINTENANCE FEE, 4TH YEAR, LARGE ENTITY (ORIGINAL EVENT CODE: M1551) Year of fee payment: 4 |
|
AS | Assignment |
Owner name: JPMORGAN CHASE BANK, N.A., AS AGENT, ILLINOIS Free format text: SECURITY INTEREST;ASSIGNOR:WESTERN DIGITAL TECHNOLOGIES, INC.;REEL/FRAME:052915/0566 Effective date: 20200113 |
|
AS | Assignment |
Owner name: WESTERN DIGITAL TECHNOLOGIES, INC., CALIFORNIA Free format text: RELEASE OF SECURITY INTEREST AT REEL 052915 FRAME 0566;ASSIGNOR:JPMORGAN CHASE BANK, N.A.;REEL/FRAME:059127/0001 Effective date: 20220203 |
|
MAFP | Maintenance fee payment |
Free format text: PAYMENT OF MAINTENANCE FEE, 8TH YEAR, LARGE ENTITY (ORIGINAL EVENT CODE: M1552); ENTITY STATUS OF PATENT OWNER: LARGE ENTITY Year of fee payment: 8 |
|
AS | Assignment |
Owner name: JPMORGAN CHASE BANK, N.A., ILLINOIS Free format text: PATENT COLLATERAL AGREEMENT - A&R LOAN AGREEMENT;ASSIGNOR:WESTERN DIGITAL TECHNOLOGIES, INC.;REEL/FRAME:064715/0001 Effective date: 20230818 Owner name: JPMORGAN CHASE BANK, N.A., ILLINOIS Free format text: PATENT COLLATERAL AGREEMENT - DDTL LOAN AGREEMENT;ASSIGNOR:WESTERN DIGITAL TECHNOLOGIES, INC.;REEL/FRAME:067045/0156 Effective date: 20230818 |