Hard-biased, soft-bias side shields for read head designs

Abstract

The present disclosure generally relates to a magnetic storage device, such as a tape drive, including a read head. The read head includes a plurality of read sensors disposed between a lower shield and an upper shield. A plurality of soft-bias side shields are disposed adjacent to and outside the plurality of read sensors in a cross-track direction. A plurality of hard-bias side shields are disposed on and in contact with the soft-bias side shields to stabilize the soft-bias side shields. Each of the plurality of soft-bias side shields is spaced apart from the lower shield by a first distance, and each of the hard-bias side shields is spaced apart from the upper shield by a second distance, the first distance being substantially equal to the second distance.

Description

Technical Field

[0001] Embodiments of the present disclosure generally relate to magnetic storage devices (eg, tape drives) including read heads and methods of forming the same. Background Art

[0002] A magnetic tape data storage device is a system for storing digital information on magnetic tape using digital recording. Magnetic tape storage media is typically packaged in cartridges or cassettes. A tape drive writes or reads data from the cartridges or cassettes. A common tape cartridge format is LTO, which comes in various densities.

[0003] A tape drive operates by recording and reading back information from a magnetic tape using a tape head through a magnetic process. The tape head may have servo elements and data elements arranged in an array sometimes referred to as a tape head array.

[0004] Hard bias elements adjacent to sensors in tape drives can have high coercivity, which can hinder device performance. Soft bias elements have lower coercivity but are unstable and may even move during tape drive operation. Soft bias elements can also cause signal shunting, hindering device performance.

[0005] Therefore, there is a need in the art for a tape drive having a soft biasing element that facilitates low coercivity, stability of the soft biasing element, reduced signal shunting, and enhanced device performance. Summary of the Invention

[0006] The present disclosure generally relates to a magnetic storage device, such as a tape drive, including a read head. The read head includes a plurality of read sensors disposed between a lower shield and an upper shield. A plurality of soft-bias side shields are disposed adjacent to and outside the plurality of read sensors in a cross-track direction. A plurality of hard-bias side shields are disposed on and in contact with the soft-bias side shields to stabilize the soft-bias side shields. Each of the plurality of soft-bias side shields is spaced apart from the lower shield by a first distance, and each of the hard-bias side shields is spaced apart from the upper shield by a second distance, the first distance being substantially equal to the second distance.

[0007] In one embodiment, a read head includes: a lower shield; an upper shield; one or more lower leads disposed above the lower shield; one or more upper leads disposed between the one or more lower leads and the upper shield; a plurality of read sensors disposed between the one or more lower leads and the one or more upper leads at a medium-facing surface, each of the plurality of read sensors comprising a multi-layer structure; a plurality of soft bias side shields disposed between and outside the plurality of read sensors; and a plurality of hard bias side shields disposed on and in contact with the plurality of soft bias side shields.

[0008] In another embodiment, a read head includes: a lower shield; a lower lead disposed above the lower shield; an antiferromagnetic (AFM) layer disposed above the lower lead; a first layer disposed on the AFM layer; and a plurality of read sensors disposed above the first layer at a media facing surface (MFS), each of the plurality of read sensors comprising a multilayer structure including a portion of the AFM layer and a portion of the first layer. The read head further includes: a plurality of soft-bias side shields disposed between and outside the plurality of read sensors; a plurality of hard-bias side shields disposed in contact with the plurality of soft-bias side shields; one or more upper leads disposed above the plurality of read sensors; and an upper shield disposed above the one or more upper leads.

[0009] In yet another embodiment, a read head includes: a lower shield; an upper shield; one or more lower leads disposed above the lower shield; one or more upper leads disposed between the one or more lower leads and the upper shield; and a plurality of read sensors disposed between the one or more lower leads and the one or more upper leads at a media-facing surface, wherein each of the plurality of read sensors includes a multilayer structure comprising: a buffer layer; an AFM layer disposed above the buffer layer; a free layer disposed above the AFM layer, the free layer including a first layer and a second layer; a barrier layer disposed above the free layer; and a cap layer disposed above the barrier layer. The read head further includes: a plurality of soft-bias side shields disposed adjacent to and outside the second layer, the barrier layer, and the cap layer of each read sensor; and a plurality of hard-bias side shields disposed on and in contact with the plurality of soft-bias side shields. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] In order that the above-mentioned features of the present disclosure may be understood in detail, the disclosure, briefly summarized above, may be more particularly described with reference to embodiments, some of which are illustrated in the accompanying drawings. It should be noted, however, that the drawings illustrate only typical embodiments of the present disclosure and are therefore not to be considered limiting of the scope of the present disclosure, as the disclosure may admit to other equally effective embodiments.

[0011] Figure 1 is a schematic perspective exploded view of a storage device according to one embodiment.

[0012] Figure 2 According to an embodiment Figure 1 Schematic top view of the tape drive described in .

[0013] Figure 3 According to an embodiment Figure 1 Schematic side profile view of the tape drive illustrated in .

[0014] Figures 4A to 4C A schematic diagram illustrating a read head according to one embodiment.

[0015] Figures 4D to 4E A schematic diagram illustrating a read head according to another embodiment.

[0016] Figures 5 to 11 Various examples of read heads according to various implementations are described.

[0017] 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. DETAILED DESCRIPTION

[0018] In the following, reference is made to embodiments of the present disclosure. However, it should be understood that the present disclosure is not limited to the specific described embodiments. In fact, any combination of the following features and elements, whether or not related to different embodiments, is encompassed to implement and practice the present disclosure. In addition, although embodiments of the present disclosure can achieve advantages over other possible solutions and / or over the prior art, whether a particular advantage is achieved by a given embodiment does not limit the present disclosure. Therefore, the following aspects, features, embodiments and advantages are merely illustrative and are not considered elements or limitations of the appended claims unless expressly stated in the claims. Similarly, reference to "the present disclosure" should not be interpreted as a generalization of any inventive subject matter disclosed herein, and should not be considered elements or limitations of the appended claims unless expressly stated in the claims.

[0019] The present disclosure generally relates to a magnetic storage device, such as a tape drive, including a read head. The read head includes a plurality of read sensors disposed between a lower shield and an upper shield. A plurality of soft-bias side shields are disposed adjacent to and outside the plurality of read sensors in a cross-track direction. A plurality of hard-bias side shields are disposed on and in contact with the soft-bias side shields to stabilize the soft-bias side shields. Each of the plurality of soft-bias side shields is spaced apart from the lower shield by a first distance, and each of the hard-bias side shields is spaced apart from the upper shield by a second distance, the first distance being substantially equal to the second distance.

[0020] Figure 1is a schematic perspective exploded view of a storage device 100 according to one embodiment. Storage device 100 is a magnetic media drive. Storage device 100 will hereinafter be referred to as tape drive 100. It should be noted that while the tape drive is shown with an embedded magnetic tape for illustrative purposes, embodiments of the present invention are applicable to various forms of tape drives, including drives in which magnetic tape media can be inserted, for example, into a media bay. An example is a tape drive and media compliant with the LTO standard, and the various drive illustrations shown will resemble such a drive when the media is fully inserted and engageable for data access.

[0021] Figure 2 According to an embodiment Figure 1 Schematic top view of the tape drive 100 illustrated in FIG.

[0022] Figure 3 According to an embodiment Figure 1 Schematic side profile view of the tape drive 100 illustrated in FIG.

[0023] focus on Figure 2 For example, the tape drive 100 includes a housing including a casing 105; one or more tape reels 110; one or more rotors (e.g., a stepper motor 120 (also known as a stepper motor), a voice coil motor (VCM) 125); a head assembly 130 having one or more read heads and one or more write heads; and tape guides / rollers 135a, 135b. Figure 3 For example, the tape drive 100 further includes a printed circuit board assembly 155 (PCBA). In one embodiment that may be combined with other embodiments, most components are within the interior cavity of the housing 105, except for the PCBA 155 mounted on the outer surface of the housing 105. Figure 1 The same components are illustrated in the perspective diagram in .

[0024] In the illustrated embodiment, two tape reels 110 are placed in the interior cavity of the housing 105, with the center of each of the two tape reels 110 being at the same level in the cavity. Figure 1 and 2As shown in FIG, a head assembly 130 is located between and below the two tape reels 110. A tape reel motor located in the spindle of the tape reel 110 is operable to wind the tape medium 115 onto and unwind it from the tape reel 110. Each tape reel 110 may also incorporate a tape folder to help neatly wind the tape medium 115 onto the corresponding tape reel 110. The tape medium 115 may be manufactured using a sputtering process to provide improved surface density. The tape medium 115 includes two surfaces, an oxide side and a substrate side. The oxide side is the surface that can be magnetically controlled (written to or read from) by one or more read / write heads. The substrate side of the tape medium 115 helps to increase the strength and flexibility of the tape medium 115.

[0025] The tape media 115 from the tape reel 110 is biased against guides / rollers 135a, 135b (collectively referred to as guides / rollers 135) and is transferred along the movement of the head assembly 130 by the movement of the reel. The illustrated embodiment shows four guides / rollers 135a, 135b, with the two guides / rollers 135a being farthest from the head assembly 130 for changing the direction of the tape media 115 and the two guides / rollers 135b being closest to the head assembly 130 for pressing the tape media 115 against the head assembly 130.

[0026] In one embodiment, which may be combined with other embodiments, the guide / roller 135 utilizes the same structure, such as Figure 1 In one embodiment, which may be combined with other embodiments, the guides / rollers 135 may have more specific shapes and differ from each other based on function, such as Figure 2 As shown in . A smaller or larger number of rollers can be used. For example, the two functional rollers can be cylindrical in shape, while the two functional guides can be flat-sided (e.g., rectangular prisms) or in the shape of a clamp with two prongs and a film moving between the prongs of the clamp.

[0027] The voice coil motor 125 and the stepper motor 120 can variably position the tape head laterally relative to the width of the recording tape (e.g., the tape medium 115). The stepper motor 120 can provide coarse movement, while the voice coil motor 125 can provide finer actuation of the head of the head assembly 130. In one embodiment, which can be combined with other embodiments, servo data can be written to the tape medium 115 to help more accurately position the head along the tape medium 115.

[0028] like Figure 1As described in

[0045] , the housing 105 includes one or more particle filters 141 and / or desiccant 142 to help maintain the environment within the housing 105. For example, if the housing 105 is not airtight, the particle filter 141 can be placed in a location where airflow is desired. The particle filter 141 and / or desiccant 142 can be placed in one or more corners or any other convenient location away from moving internal components. For example, the moving tape reel 110 can generate an internal airflow when the tape media 115 is wound / unwound, and the particle filter 141 can be placed within the airflow.

[0029] There are various possible placements of the internal components of the tape drive 100 within the housing 105. Specifically, in some instances, when the head assembly 130 is inside the housing 105, the tape media 115 may not be exposed to the exterior of the housing 105. Thus, the tape media 115 need not be routed along the edge of the housing 105 and may be freely routed within the housing 105 in a more compact and / or otherwise efficient manner. Similarly, the head and tape reel 110 may be placed in a variety of locations to achieve a more efficient layout because there is no design requirement to provide external access to these components.

[0030] like Figure 3 As illustrated in FIG, housing 105 includes a lid 150 and a base 145. A PCBA 155 is attached to the outer surface of housing 105, at the bottom opposite lid 150. Base 145 includes three walls, and lid 150 includes a fourth wall, forming four of the multiple walls of housing 105 contained within the outer shell of tape drive 100. Because PCBA 155 is made of solid-state electronics, environmental concerns are less of a concern, and therefore, it does not need to be placed inside housing 105. This leaves space inside housing 105 for other components that would benefit from a more protected environment, particularly moving components and tape media 115.

[0031] In one embodiment that can be combined with other embodiments, the tape drive 100 is sealed. Sealing can mean that the tape drive 100 is hermetically sealed or simply enclosed, and is not necessarily airtight. A sealed drive can be beneficial to tape film winding stability, tape film reliability, and tape head reliability. A desiccant can be used to limit the humidity inside the housing 105.

[0032] In one embodiment, which may be combined with other embodiments, the cover 150 is used to hermetically seal the tape drive 100. For example, the tape drive 100 may be hermetically sealed for environmental control by attaching (e.g., laser welding, adhering with an adhesive, etc.) the cover 150 to the base 145. The tape drive 100 may be filled with helium, nitrogen, hydrogen, or any other typical inert gas.

[0033] In one embodiment that can be combined with other embodiments, other components can be added to the tape drive 100. For example, a preamplifier for the magnetic head of the head assembly 130 can be added to the tape drive 100. The preamplifier can be located on the PCBA 155, in the head assembly 130, or in another location. Generally speaking, placing the preamplifier closer to the magnetic head can have a greater impact on the signal-to-noise ratio (SNR) of the read and write signals. In one embodiment that can be combined with other embodiments, some components can be omitted. For example, the particle filter 141 and / or the desiccant 142 can be omitted.

[0034] Figures 4A to 4C A schematic diagram illustrating a read head 400 according to one embodiment is shown. Figure 4A is a schematic isometric media facing surface (MFS) view of a read head 400 according to one embodiment. Figure 4B According to an embodiment Figure 4A A schematic isometric side cross-sectional view of a read head 400 is shown in FIG. Figure 4C According to an embodiment Figure 4A Schematic cross-sectional view of the read head 400 along section 4C-4C shown in FIG.

[0035] The read head 400 can be used as Figure 1 A portion of the tape drive 100 (magnetic storage device) shown in FIG. The read head 400 includes a lower shield (S1) 402, an upper shield (S2) 404, and a plurality of read sensors 420 disposed between the lower shield 402 and the upper shield 404. Figure 4A Three read sensors 420 are shown in FIG, but the read head 400 may include any number of read sensors 420 and the number of read sensors 420 is not intended to be limiting.

[0036] The lower lead 406 is disposed between the lower shield 402 and the plurality of read sensors 420. Figure 4AAs shown in FIG, lower leads 406 are common to each read sensor 420. However, in some embodiments, each read sensor 420 may have a separate lower lead 406 (not shown). Read head 400 includes a plurality of upper leads 416 disposed above each of the plurality of read sensors 420 in a down-track direction (DT1). Similar to lower leads 406, upper leads 416 may be a single upper lead 416 common to each read sensor 420. A first insulating layer 412 is disposed between upper shield 404 and the plurality of upper leads 416. A second insulating layer 408 is disposed on lower leads 406 and surrounds each of read sensors 420 in the down-track direction. A third insulating layer 440 is disposed adjacent to and between each of the plurality of upper leads 416. Each of first insulating layer 412, second insulating layer 408, and third insulating layer 440 may comprise the same material or different materials.

[0037] Each of the plurality of read sensors 420 includes a multilayer structure. The multilayer structure of each read sensor 420 includes a buffer layer 422 disposed on the bottom lead 406, an antiferromagnetic (AFM) layer 424 disposed on the buffer layer 422, and a free layer 426 disposed on the AFM layer 424. Each read sensor 420 includes a cap layer 428 disposed on the free layer 426. The buffer layer 422 is disposed between the AFM layer 424 and the bottom lead 406. The buffer layer 422 is substantially aligned with a portion of the second insulating layer 408 in the cross-track direction (CT1). The cap layer 428 is non-ferromagnetic. The length of each layer 422, 424, 426, 428 in each read sensor 420 in the cross-track direction is less than the length of the bottom shield 402 in the cross-track direction.

[0038] The free layer 426 of each read sensor 420 includes a plurality of layers 430-433. The free layer 426 is ferromagnetic. The free layer 426 includes two layers, namely, a first layer 430 and a second layer 432, separated by a spacer layer 431. Each of the two layers 430 and 432 is formed from one or more of cobalt (Co), iron (Fe), and / or boron (B). The spacer layer 431 is formed from magnesium oxide (MgO) and has a length in the downtrack direction DT1 ranging from approximately 5 angstroms to approximately 200 angstroms, for example, approximately 20 angstroms. The barrier layer 433 of the free layer 426 is disposed between the second layer 432 and the cap layer 428.

[0039] The read head 400 includes a plurality of soft bias side shields 410 disposed between and outside a plurality of read sensors 420, disposed on and in contact with the second insulating layer 408. Each of the soft bias side shields 410 is magnetic, conductive, and has low coercivity. The soft bias side shields 410 help bias the magnetic read field of the read sensors 420 during a magnetic read operation. The soft bias side shields 410 promote a magnetic field in a cross-track direction during a magnetic read operation.

[0040] The plurality of hard-bias side shields 460 are positioned in contact with the plurality of soft-bias side shields 410 and the third insulating layer 440. The plurality of hard-bias side shields 460 are spaced apart from the sensor 420 by the plurality of soft-bias side shields 410. Depending on various designs, the thickness T1 of the plurality of soft-bias side shields 410 in the down-track direction (DT1) is different from or equal to the thickness T2 of the plurality of hard-bias side shields 460 in the down-track direction. The plurality of hard-bias side shields 460 have high coercivity and fix the magnetization of the soft-bias side shields 410 in a desired direction, such as in a cross-track direction. The plurality of hard-bias side shields 460 help stabilize the plurality of soft-bias side shields 410 to enhance magnetic reading operations while minimizing signal shunting.

[0041] Figure 4B According to an embodiment Figure 4A Schematic isometric side cross-sectional view of the read head 400 shown in FIG. Figure 4B As shown in the figure, the lower shield 402, the lower lead 406, the second insulating layer 408, the soft bias side shield 410, the hard bias side shield 460, the third insulating layer 440, the read sensor 420, the first insulating layer 412 and the upper shield 404 each have a first width W1 in the strip height direction (SH1) from the MFS to the first surface 401 opposite to the MFS.

[0042] Figure 4C According to an embodiment Figure 4A Schematic cross-sectional view of the read head 400 along section 4C-4C shown in FIG. Figure 4C The general cross-section shown in Figures 4D to 11 The read head 490-1100 is shown in FIG. The lower lead 406 has a third thickness T3. The first insulating layer 412, the third insulating layer 440, and the upper lead 416 between the upper shield 404 and the hard bias side shield 460 collectively have a fourth thickness T4. The fourth thickness T4 is substantially equal to the third thickness T3, such that the difference between the fourth thickness T4 and the third thickness T3 is approximately 50 nm or less. The fourth thickness T4 being substantially equal to the third thickness T3 facilitates stabilization of the read sensor 420 by helping to stabilize the soft bias side shield 410, thereby enhancing magnetic read operation while minimizing signal shunting.

[0043] During a magnetic read operation, the tape medium 450 moves in a downtrack direction past the read sensor 420. A portion 452 of the tape medium 450 aligned with the read sensor 420 along the stripe height direction is subjected to a first magnetic force F1. A portion 454 of the tape medium 450 aligned outside of the read sensor 420 along the stripe height direction is subjected to a second magnetic force F2 that is opposite in direction to or in the same direction as the first magnetic force F1.

[0044] Figures 4D to 4E A schematic diagram illustrating a read head 490 according to another embodiment is shown. Figure 4D is a schematic isometric MFS view of a read head 490 according to one embodiment. Figure 4E is a schematic isometric side view of a read head 490 according to one embodiment. The read head 490 may be used as Figure 1 A portion of a tape drive 100 (magnetic storage device) is shown in FIG. Figures 4D to 4E The read head 490 is similar to Figures 4A to 4C Thus, for aspects that are identical in each read head 400, 490, Figures 4A to 4C and Figures 4D to 4E Similar reference numerals are used in FIG.

[0045] like Figure 4D As shown in FIG, the read head 490 includes Figures 4A to 4C The same components as the read head 400 of FIG. 4 include a plurality of read sensors 420, a plurality of soft bias side shields 410, and a plurality of hard bias side shields 460. However, as Figure 4E As shown in FIG, the lower shield 402 and the lower lead 406 each have a first width W1 in the strip height direction from the MFS to the first surface 401 opposite the MFS. The second insulating layer 408, the soft bias side shield 410, the hard bias side shield 460, the third insulating layer 440, the read sensor 420, the first insulating layer 412, and the upper shield 404 each have a second width W2 in the strip height direction from the MFS to the second surface 403 opposite the MFS. The first width W1 is greater than the second width W2. In other words, the first surface 401 and the second surface 403 are not aligned.

[0046] In addition, as mentioned above Figure 4C, the lower lead 406 has a third thickness T3. The first insulating layer 412, the third insulating layer 440, and the upper lead 416 between the upper shield 404 and the hard bias side shield 460 collectively have a fourth thickness T4. The fourth thickness T4 is substantially equal to the third thickness T3, such that the difference between the fourth thickness T4 and the third thickness T3 is approximately 50 nm or less. The fourth thickness T4 being substantially equal to the third thickness T3 facilitates stabilization of the read sensor 420 by helping to stabilize the soft bias side shield 410, thereby enhancing magnetic read operation while minimizing signal shunting.

[0047] In addition to the third thickness T3 and the fourth thickness T4 being substantially equal, Figures 4D to 4E The soft bias side shield 410 is further stabilized by shape anisotropy, wherein the soft bias side shield has a second width W2 in the strip height direction that is smaller than the first width W1. The shape of the soft bias side shield 410 and the resulting shape anisotropy fix the magnetization of the soft bias side shield 410 in a desired direction, such as the cross-track direction.

[0048] Figure 5 is a schematic isometric MFS view of a read head 500 according to one embodiment. The read head 500 may be used as Figure 1 A portion of a tape drive 100 (magnetic storage device) is shown in FIG. Figure 5 The read head 500 is similar to Figures 4A to 4C The read head 400 and Figures 4D to 4E Thus, for aspects that are identical in each of the read heads 400, 490, 500, Figures 4A to 4E and Figure 5 Similar reference numerals are used in FIG.

[0049] although Figure 5 Three read sensors 520 are shown in FIG, but the read head 500 may include any number of read sensors 520 and the number of read sensors 520 is not intended to be limiting. Figure 5 As shown in FIG, the lower leads 406 are common to each read sensor 520, while the upper leads 416 are independent for each read sensor 520. However, in some embodiments, each read sensor 520 may have a separate lower lead 406 (not shown). In other embodiments, the upper leads 416 may be common to each read sensor 520.

[0050] Each of the plurality of read sensors 520 includes a multilayer structure. The multilayer structure of each read sensor 520 includes a buffer layer 422 disposed on the bottom lead 406, an AFM layer 424 disposed on the buffer layer 422, and a free layer 526 disposed on the AFM layer 424. Each read sensor 520 includes a cap layer 428 disposed on the free layer 526. The buffer layer 422 is disposed between the AFM layer 424 and the bottom lead 406. The cap layer 428 is non-ferromagnetic. The length of each layer 422, 424, 526, 428 in each read sensor 520 in the cross-track direction is shorter than the length of the bottom shield 402 in the cross-track direction.

[0051] The free layer 526 of each read sensor 520 includes a plurality of layers 430-433. The free layer 526 is ferromagnetic. The free layer 526 includes two layers, namely, a first layer 430 and a second layer 432, separated by a spacer layer 431. The barrier layer 433 of the free layer 526 is disposed between the second layer 432 and the cap layer 428. The lower shield 402, the lower lead 406, the second insulating layer 408, the soft bias side shield 410, the hard bias side shield 460, the third insulating layer 440, the read sensor 520, the first insulating layer 412, and the upper shield 404 each have a first width W1 in the stripe height direction from the MFS to the first surface 401 opposite the MFS.

[0052] Read head 500 and Figures 4A to 4C The read head 400 of FIG5 is different because the plurality of soft bias side shields 410 are positioned adjacent only to portions of the sensor 520. Specifically, the plurality of soft bias side shields 410 are positioned adjacent only to the spacer layer 431, the second layer 432, the barrier layer 433, and the cap layer 428. The second insulating layer 408 is positioned between the plurality of soft bias side shields 410 and the spacer layer 431, the second layer 432, the barrier layer 433, and the cap layer 428. The plurality of hard bias side shields 460 are positioned adjacent to and in contact with the plurality of soft bias side shields 410 in the cross-track direction.

[0053] The non-magnetic layer 562 is disposed between the second insulating layer 408 and the plurality of hard bias side shields 460. The non-magnetic layer 562 has a fifth thickness T5 in the downtrack direction, and the plurality of hard bias side shields 460 have a sixth thickness T6 in the downtrack direction. Depending on various designs, the fifth thickness T5 may be different from or substantially equal to the sixth thickness T6.

[0054] The soft-bias side shields 410 help bias the magnetic read field of the read sensor 520 during magnetic read operations. The soft-bias side shields 410 promote a magnetic field in the cross-track direction during magnetic read operations. The plurality of hard-bias side shields 460 fix the magnetization of the soft-bias side shields 410 in a desired direction, such as the cross-track direction. The plurality of hard-bias side shields 460 stabilize the plurality of soft-bias side shields 410 to enhance magnetic read operations while minimizing signal shunting.

[0055] In addition, as mentioned above Figure 4C As discussed and illustrated in FIG, the lower lead 406 has a third thickness T3. The first insulating layer 412, the third insulating layer 440, and the upper lead 416 between the upper shield 404 and the hard bias side shield 460 and / or the soft bias side shield 410 collectively have a fourth thickness T4. The fourth thickness T4 is substantially equal to the third thickness T3, such that the difference between the fourth thickness T4 and the third thickness T3 is approximately 50 nm or less. The fourth thickness T4 being substantially equal to the third thickness T3 facilitates stabilization of the read sensor 520 by helping to stabilize the soft bias side shield 410, thereby enhancing magnetic read operation while minimizing signal shunting.

[0056] Figure 6 is a schematic isometric MFS view of a read head 600 according to one embodiment. The read head 600 may be used as Figure 1 A portion of a tape drive 100 (magnetic storage device) is shown in FIG. Figure 6 The read head 600 is similar to Figures 4A to 4C Read head 400, Figures 4D to 4E The read head 490 and Figure 5 Thus, for aspects that are identical in each of the read heads 400, 490, 500, 600, Figures 4A to 5 and Figure 6 Similar reference numerals are used in FIG.

[0057] although Figure 6 Three read sensors 620 are shown in FIG, but the read head 600 may include any number of read sensors 620 and the number of read sensors 620 is not intended to be limiting. Figure 6 As shown in FIG, the lower leads 406 are common to each read sensor 620, while the upper leads 416 are independent for each read sensor 620. However, in some embodiments, each read sensor 620 may have a separate lower lead 406 (not shown). In other embodiments, the upper leads 416 are common to each read sensor 620.

[0058] Each of the plurality of read sensors 620 includes a multilayer structure. The multilayer structure of each read sensor 620 includes a buffer layer 422 disposed on the bottom lead 406, an AFM layer 424 disposed on the buffer layer 422, and a free layer 626 disposed on the AFM layer 424. Each read sensor 620 includes a cap layer 428 disposed on the free layer 626. The buffer layer 422 is disposed between the AFM layer 424 and the bottom lead 406. The cap layer 428 is non-ferromagnetic. The length of each layer 422, 424, 626, 428 in each read sensor 620 in the cross-track direction is shorter than the length of the bottom shield 402 in the cross-track direction.

[0059] The free layer 626 of each read sensor 620 includes a plurality of layers 430-433. The free layer 626 is ferromagnetic. The free layer 626 includes two layers, namely, a first layer 430 and a second layer 432, separated by a spacer layer 431. The barrier layer 433 of the free layer 626 is positioned between the second layer 432 and the cap layer 428. The lower shield 402, the lower lead 406, the second insulating layer 408, the nonmagnetic layer 562, the third insulating layer 440, the first insulating layer 412, and the upper shield 404 each have a first width W1 in the stripe height direction from the MFS to the first surface 401 opposite the MFS.

[0060] The read head 600 is similar to Figure 5 The read head 500 is configured as shown in FIG. 5 because the plurality of soft-bias side shields 410 are positioned adjacent only to a portion of the sensor 620. Specifically, the plurality of soft-bias side shields 410 are positioned adjacent only to the spacer layer 431, the second layer 432, the barrier layer 433, and the cap layer 428. The second insulating layer 408 is positioned between the plurality of soft-bias side shields 410 and the spacer layer 431, the second layer 432, the barrier layer 433, and the cap layer 428. The plurality of hard-bias side shields 460 are positioned adjacent to and in contact with the plurality of soft-bias side shields 410 in the cross-track direction.

[0061] The non-magnetic layer 562 is disposed between the second insulating layer 408 and the plurality of hard bias side shields 460. The non-magnetic layer 562 has a fifth thickness T5 in the downtrack direction, and the plurality of hard bias side shields 460 have a sixth thickness T6 in the downtrack direction. Depending on various designs, the fifth thickness T5 may be different from or substantially equal to the sixth thickness T6.

[0062] Read head 600 and Figure 5The read head 500 differs in that a fourth insulating layer 668 is positioned behind the plurality of hard-bias side shields 460. The fourth insulating layer 668 is positioned in contact with the nonmagnetic layer 562, the third insulating layer 440, the soft-bias side shields 410, the cap layer 428, the barrier layer 433 of the free layer 626, the second layer 432 of the free layer 626, the spacer layer 431 of the free layer 626, a portion of the second insulating layer 408, and the plurality of hard-bias side shields 460. The fourth insulating layer 668 is recessed from the MFS and has a third width W3 in the stripe height direction. The third width W3 is greater than or equal to a fourth width W4 of the plurality of hard-bias side shields 460 in the stripe height direction. The fourth insulating layer 668 may include the same material as the first insulating layer 412 or a different material.

[0063] The soft-bias side shields 410 help bias the magnetic read field of the read sensor 620 during magnetic read operations. The soft-bias side shields 410 promote a magnetic field in the cross-track direction during magnetic read operations. The plurality of hard-bias side shields 460 fix the magnetization of the soft-bias side shields 410 in a desired direction, such as the cross-track direction. The plurality of hard-bias side shields 460 stabilize the plurality of soft-bias side shields 410 to enhance magnetic read operations while minimizing signal shunting.

[0064] In addition, as mentioned above Figure 4C As discussed and shown in FIG, the lower lead 406 has a third thickness T3. The first insulating layer 412, the third insulating layer 440, and the upper lead 416 between the upper shield 404 and the hard bias side shield 460 and / or the soft bias side shield 410 collectively have a fourth thickness T4. The fourth thickness T4 is substantially equal to the third thickness T3, such that the difference between the fourth thickness T4 and the third thickness T3 is approximately 50 nm or less. The fourth thickness T4 being substantially equal to the third thickness T3 facilitates stabilization of the read sensor 620 by helping to stabilize the soft bias side shield 410, thereby enhancing magnetic read operation while minimizing signal shunting.

[0065] Figure 7 is a schematic isometric MFS view of a read head 700 according to one embodiment. The read head 600 may be used as Figure 1 A portion of a tape drive 100 (magnetic storage device) is shown in FIG. Figure 7 The read head 700 is similar to Figures 4A to 4C Read head 400, Figures 4D to 4E Read head 490, Figure 5 The read head 500 and Figure 6 Thus, for aspects that are identical in each of the read heads 400, 490, 500, 600, 700, Figures 4A to 6 and Figure 7 Similar reference numerals are used in FIG.

[0066] although Figure 7 Three read sensors 720 are shown in FIG, but the read head 700 may include any number of read sensors 720 and the number of read sensors 720 is not intended to be limiting. Figure 7 As shown in FIG, the lower leads 406 are common to each read sensor 720, while the upper leads 416 are independent for each read sensor 720. However, in some embodiments, each read sensor 720 may have a separate lower lead 406 (not shown). In other embodiments, the upper leads 416 may be common to each read sensor 720.

[0067] Each of the plurality of read sensors 720 includes a multilayer structure. The multilayer structure of each read sensor 720 includes a buffer layer 422 disposed on the bottom lead 406, an AFM layer 424 disposed on the buffer layer 422, and a free layer 726 disposed on the AFM layer 424. Each read sensor 720 includes a cap layer 428 disposed on the free layer 726. The buffer layer 422 is disposed between the AFM layer 424 and the bottom lead 406. The cap layer 428 is non-ferromagnetic. The length of each layer 422, 424, 726, 428 in each read sensor 720 in the cross-track direction is shorter than the length of the bottom shield 402 in the cross-track direction.

[0068] The free layer 726 of each read sensor 720 includes a plurality of layers 430-433. The free layer 726 is ferromagnetic. The free layer 726 includes two layers, namely, a first layer 430 and a second layer 432, separated by a spacer layer 431. The barrier layer 433 of the free layer 726 is positioned between the second layer 432 and the cap layer 428. The lower shield 402, the lower lead 406, the third insulating layer 440, the first insulating layer 412, and the upper shield 404 each have a first width W1 in the stripe height direction from the MFS to the first surface 401 opposite the MFS.

[0069] The read head 700 is similar to Figures 4A to 4C The read head 400 is configured such that the plurality of soft bias side shields 410 are positioned adjacent to each layer of the sensor 720 on the second insulating layer 408. The plurality of hard bias side shields 460 are positioned on the plurality of soft bias side shields 410 adjacent to the third insulating layer 440. Figures 4A to 4CThe read head 400 of FIG. 1 differs in that a fifth insulating layer 770 is positioned behind the plurality of hard bias side shields 460, the plurality of soft bias side shields 410, the sensor 720, and the second insulating layer 408. The fifth insulating layer 770 is positioned in contact with the lower lead 406 and the third insulating layer 440. The fifth insulating layer 770 is recessed from the MFS and has a third width W3 in the stripe height direction. The plurality of hard bias side shields 460, the plurality of soft bias side shields 410, and the read sensor 720 each have a fourth width W4 in the stripe height direction. The third width W3 is greater than or equal to the fourth width W4 in the stripe height direction.

[0070] The fifth insulating layer 770 further has a seventh thickness T7 in the downtrack direction. The plurality of hard bias side shields 460 have an eighth thickness T8 in the downtrack direction, and the plurality of soft bias side shields 410 have a ninth thickness T9 in the downtrack direction. The seventh thickness T7 is greater than the eighth thickness T8 and the ninth thickness T9. The fifth insulating layer 770 may include the same material as the first insulating layer 412 or a different material.

[0071] The soft-bias side shields 410 help bias the magnetic read field of the read sensor 720 during magnetic read operations. The soft-bias side shields 410 promote a magnetic field in the cross-track direction during magnetic read operations. The plurality of hard-bias side shields 460 fix the magnetization of the soft-bias side shields 410 in a desired direction, such as the cross-track direction. The plurality of hard-bias side shields 460 stabilize the plurality of soft-bias side shields 410 to enhance magnetic read operations while minimizing signal shunting.

[0072] In addition, as mentioned above Figure 4C , the lower lead 406 has a third thickness T3. The first insulating layer 412, the third insulating layer 440, and the upper lead 416 between the upper shield 404 and the hard bias side shield 460 collectively have a fourth thickness T4. The fourth thickness T4 is substantially equal to the third thickness T3, such that the difference between the fourth thickness T4 and the third thickness T3 is approximately 50 nm or less. The fourth thickness T4 being substantially equal to the third thickness T3 facilitates stabilization of the read sensor 720 by helping to stabilize the soft bias side shield 410, thereby enhancing magnetic read operation while minimizing signal shunting.

[0073] Figure 8 is a schematic isometric MFS view of a read head 800 according to one embodiment. The read head 800 may be used as Figure 1 A portion of a tape drive 100 (magnetic storage device) is shown in FIG. Figure 8 The read head 800 is similar to Figures 4A to 4C Read head 400, Figures 4D to 4E Read head 490, Figure 5 Read head 500, Figure 6 The read head 600 and Figure 7 Thus, for aspects that are identical in each of the read heads 400, 490, 500, 600, 700, 800, Figures 4A to 7 and Figure 8 Similar reference numerals are used in FIG.

[0074] although Figure 8 Three read sensors 820 are shown in FIG, but the read head 800 may include any number of read sensors 820 and the number of read sensors 820 is not intended to be limiting. Figure 8 As shown in FIG, the lower leads 406 are common to each read sensor 820, while the upper leads 416 are independent for each read sensor 820. However, in some embodiments, each read sensor 820 may have a separate lower lead 406 (not shown). In other embodiments, the upper leads 416 may be common to each read sensor 820.

[0075] Each of the plurality of read sensors 820 includes a multilayer structure. The multilayer structure of each read sensor 820 includes a buffer layer 422 disposed on the bottom lead 406, an AFM layer 424 disposed on the buffer layer 422, and a free layer 826 disposed on the AFM layer 424. Each read sensor 420 includes a cap layer 428 disposed on the free layer 826. The buffer layer 422 is disposed between the AFM layer 424 and the bottom lead 406. The cap layer 428 is non-ferromagnetic. The buffer layer 422 and the AFM layer 424 are common to each of the sensors 820. In other words, each sensor 820 includes a portion of the buffer layer 422 and a portion of the AFM layer 424, such that the common portion of the buffer layer 422 and the common portion of the AFM layer 424 are common across the plurality of read sensors 820.

[0076] The free layer 826 of each read sensor 820 includes a plurality of layers 430-433. The free layer 826 is ferromagnetic. The free layer 826 includes two layers, namely, a first layer 430 and a second layer 432, separated by a spacer layer 431. The barrier layer 433 of the free layer 826 is disposed between the second layer 432 and the cap layer 428. The lower shield 402, lower lead 406, second insulating layer 408, soft bias side shield 410, hard bias side shield 460, third insulating layer 440, read sensor 820, first insulating layer 412, and upper shield 404 each have a first width W1 in the stripe height direction from the MFS to the first surface 401 opposite the MFS. The second insulating layer 408 is disposed on the first layer 430 of the free layer 826 and surrounds each of the read sensors 820 in the downtrack direction.

[0077] Read head 800 differs from read heads 400, 490, and 500 in that each free layer 826 of each read sensor 820 shares a common first layer 430, while each read sensor 820 has its own individual spacer layer 431, second layer 432, and barrier layer 433. In other words, each sensor 820 includes a portion of first layer 430, such that the common portion of first layer 430 spans multiple read sensors 820.

[0078] In addition, similar to Figure 5 In the read head 500 of the embodiment of the present invention, the plurality of soft bias side shields 410 are positioned adjacent only to a portion of the sensor 820. Specifically, the plurality of soft bias side shields 410 are positioned adjacent only to the spacer layer 431, the second layer 432, the barrier layer 433, and the cap layer 428. The second insulating layer 408 is positioned between the plurality of soft bias side shields 410 and the spacer layer 431, the second layer 432, the barrier layer 433, and the cap layer 428. The plurality of hard bias side shields 460 are positioned adjacent to and in contact with the plurality of soft bias side shields 410 in the cross-track direction. Both the plurality of soft bias side shields 410 and the plurality of hard bias side shields 460 have a tenth thickness T10 in the downtrack direction.

[0079] The lower shield 402, lower lead 406, third insulating layer 440, first layer 430, first insulating layer 412, and upper shield 404 each have a first length L1 in the cross-track direction. The spacer layer 431, second layer 432, barrier layer 433, cap layer 428, and upper lead 416 each have a second length L2 in the cross-track direction that is less than the first length L1. The plurality of soft-bias side shields 410 each have a third length L3 in the cross-track direction, and the plurality of hard-bias side shields 460 each have a fourth length L4 in the cross-track direction that is substantially equal to or greater than the third length L3. The fourth length L4 is less than the first length L1. The length of the second insulating layer 408 in the cross-track direction is substantially equal to the sum of the third length L3 and the fourth length L4.

[0080] The soft-bias side shields 410 help bias the magnetic read field of the read sensor 820 during magnetic read operations. The soft-bias side shields 410 promote a magnetic field in the cross-track direction during magnetic read operations. The plurality of hard-bias side shields 460 fix the magnetization of the soft-bias side shields 410 in a desired direction, such as the cross-track direction. The plurality of hard-bias side shields 460 stabilize the plurality of soft-bias side shields 410 to enhance magnetic read operations while minimizing signal shunting.

[0081] In addition, as mentioned above Figure 4C, the lower lead 406 has a third thickness T3. The first insulating layer 412, the third insulating layer 440, and the upper lead 416 between the upper shield 404 and the hard bias side shield 460 collectively have a fourth thickness T4. The fourth thickness T4 is substantially equal to the third thickness T3, such that the difference between the fourth thickness T4 and the third thickness T3 is approximately 50 nm or less. The fourth thickness T4 being substantially equal to the third thickness T3 facilitates stabilization of the read sensor 820 by helping to stabilize the soft bias side shield 410, thereby enhancing magnetic read operation while minimizing signal shunting.

[0082] Figure 9 is a schematic isometric MFS view of a read head 900 according to one embodiment. The read head 900 may be used as Figure 1 A portion of a tape drive 100 (magnetic storage device) is shown in FIG. Figure 9 The read head 900 is similar to Figures 4A to 4C Read head 400, Figures 4D to 4E Read head 490, Figure 5 Read head 500, Figure 6 The read head 600 and Figure 7 The read head 700, and Figure 8 Thus, for aspects that are identical in each of the read heads 400, 490, 500, 600, 700, 800, 900, Figures 4A to 8 and Figure 9 Similar reference numerals are used in FIG.

[0083] although Figure 9 Three read sensors 920 are shown in FIG, but the read head 900 may include any number of read sensors 920 and the number of read sensors 920 is not intended to be limiting. Figure 9 As shown in FIG, the lower leads 406 are common to each read sensor 920, while the upper leads 416 are independent for each read sensor 920. However, in some embodiments, each read sensor 920 may have a separate lower lead 406 (not shown). In other embodiments, the upper leads 416 may be common to each read sensor 920.

[0084] Each of the plurality of read sensors 920 includes a multilayer structure. The multilayer structure of each read sensor 920 includes a buffer layer 422 disposed on the bottom lead 406, an AFM layer 424 disposed on the buffer layer 422, and a free layer 926 disposed on the AFM layer 424. Each read sensor 420 includes a cap layer 428 disposed on the free layer 926. The buffer layer 422 is disposed between the AFM layer 424 and the bottom lead 406. The cap layer 428 is non-ferromagnetic. The buffer layer 422 and the AFM layer 424 are common to each of the sensors 920. In other words, each sensor 920 includes a portion of the buffer layer 422 and a portion of the AFM layer 424, such that the common portion of the buffer layer 422 and the common portion of the AFM layer 424 are common across the plurality of read sensors 920.

[0085] The free layer 926 of each read sensor 920 includes a plurality of layers 430-433. The free layer 926 is ferromagnetic. The free layer 926 includes two layers, namely, a first layer 430 and a second layer 432, separated by a spacer layer 431. The barrier layer 433 of the free layer 926 is positioned between the second layer 432 and the cap layer 428. The lower shield 402, the lower lead 406, the second insulating layer 408, the third insulating layer 440, the first insulating layer 412, and the upper shield 404 each have a first width W1 in the stripe height direction from the MFS to the first surface 401 opposite the MFS.

[0086] The read head 900 is similar to Figure 8 4. The embodiment of the present invention relates to a read head 800 in which each free layer 926 of each read sensor 920 shares a common first layer 430, while each read sensor 920 has its own individual spacer layer 431, second layer 432, and barrier layer 433. In other words, each sensor 920 includes a portion of the first layer 430, such that the common portion of the first layer 430 spans across multiple read sensors 920. A second insulating layer 408 is disposed on the first layer 430 of the free layer 926 and surrounds each of the read sensors 920 in the downtrack direction.

[0087] In addition, similar to Figure 5 The read head 500 and Figure 8In the read head 800 of the embodiment of the present invention, the plurality of soft bias side shields 410 are positioned adjacent only to a portion of the sensor 920. Specifically, the plurality of soft bias side shields 410 are positioned adjacent only to the spacer layer 431, the second layer 432, the barrier layer 433, and the cap layer 428. The second insulating layer 408 is positioned between the plurality of soft bias side shields 410 and the spacer layer 431, the second layer 432, the barrier layer 433, and the cap layer 428. The plurality of hard bias side shields 460 are still positioned adjacent to and in contact with the plurality of soft bias side shields 410 in the cross-track direction. Both the plurality of soft bias side shields 410 and the plurality of hard bias side shields 460 have a tenth thickness T10 in the downtrack direction.

[0088] Read head 900 and Figure 8 The read head 800 of FIG. 1 is different because a sixth insulating layer 964 is positioned between the second insulating layer 408 and the lower lead 406 on the back side of the read head 900 (away from the MFS). The sixth insulating layer 964 may include the same material as or a different material from the first insulating layer 412. Furthermore, the sixth insulating layer 964 has a fifth width W5 in the stripe height direction and an eleventh thickness T11 in the downtrack direction. The buffer layer 422, the AFM layer 424, and the first layer 430 have a sixth width W6 in the stripe height direction. The fifth width W5 may be greater than or equal to the sixth width W6. The fifth width W5 and the sixth width W6 are collectively equal to the first width W1 of the lower shield 402, the lower lead 406, the plurality of hard bias side shields 460, the first insulating layer 412, the second insulating layer 408, the third insulating layer 440, and the upper shield 404. The eleventh thickness T11 is greater than or equal to the tenth thickness T10.

[0089] The lower shield 402, lower lead 406, third insulating layer 440, first layer 430, first insulating layer 412, and upper shield 404 each have a first length L1 in the cross-track direction. The spacer layer 431, second layer 432, barrier layer 433, cap layer 428, and upper lead 416 each have a second length L2 in the cross-track direction that is less than the first length L1. The plurality of soft-bias side shields 410 each have a third length L3 in the cross-track direction, and the plurality of hard-bias side shields 460 each have a fourth length L4 in the cross-track direction that is substantially equal to or greater than the third length L3. The fourth length L4 is less than the first length L1. The length of the second insulating layer 408 in the cross-track direction is substantially equal to the sum of the third length L3 and the fourth length L4.

[0090] The soft-bias side shields 410 help bias the magnetic read field of the read sensor 920 during magnetic read operations. The soft-bias side shields 410 promote a magnetic field in the cross-track direction during magnetic read operations. The plurality of hard-bias side shields 460 fix the magnetization of the soft-bias side shields 410 in a desired direction, such as the cross-track direction. The plurality of hard-bias side shields 460 stabilize the plurality of soft-bias side shields 410 to enhance magnetic read operations while minimizing signal shunting.

[0091] In addition, as mentioned above Figure 4C , the lower lead 406 has a third thickness T3. The first insulating layer 412, the third insulating layer 440, and the upper lead 416 between the upper shield 404 and the hard bias side shield 460 collectively have a fourth thickness T4. The fourth thickness T4 is substantially equal to the third thickness T3, such that the difference between the fourth thickness T4 and the third thickness T3 is approximately 50 nm or less. The fourth thickness T4 being substantially equal to the third thickness T3 facilitates stabilization of the read sensor 920 by helping to stabilize the soft bias side shield 410, thereby enhancing magnetic read operation while minimizing signal shunting.

[0092] Figure 10 is a schematic isometric MFS view of a read head 1000 according to one embodiment. The read head 1000 may be used as Figure 1 A portion of a tape drive 100 (magnetic storage device) is shown in FIG. Figure 10 The read head 1000 is similar to Figures 4A to 4C Read head 400, Figures 4D to 4E Read head 490, Figure 5 Read head 500, Figure 6 The read head 600 and Figure 7 Read head 700, Figure 8 The read head 800, and Figure 9 Thus, for aspects that are the same in each of the read heads 400, 490, 500, 600, 700, 800, 900, 1000, Figures 4A to 9 and Figure 10 Similar reference numerals are used in FIG.

[0093] although Figure 10 Three read sensors 1020 are shown in FIG, but the read head 1000 may include any number of read sensors 1020 and the number of read sensors 1020 is not intended to be limiting. Figure 10As shown in FIG, the lower leads 406 are common to each read sensor 1020, while the upper leads 416 are separate for each read sensor 1020. However, in some embodiments, each read sensor 1020 may have a separate lower lead 406 (not shown). In other embodiments, the upper leads 416 may be common to each read sensor 1020.

[0094] Each of the plurality of read sensors 1020 includes a multilayer structure. The multilayer structure of each read sensor 1020 includes a buffer layer 422 disposed on the bottom lead 406, an AFM layer 424 disposed on the buffer layer 422, and a free layer 1026 disposed on the AFM layer 424. Each read sensor 420 includes a cap layer 428 disposed on the free layer 1026. The buffer layer 422 is disposed between the AFM layer 424 and the bottom lead 406. The cap layer 428 is non-ferromagnetic. The buffer layer 422 and the AFM layer 424 are common to each of the sensors 1020. In other words, each sensor 1020 includes a portion of the buffer layer 422 and a portion of the AFM layer 424, such that the common portion of the buffer layer 422 and the common portion of the AFM layer 424 are common across the plurality of read sensors 1020.

[0095] The free layer 1026 of each read sensor 1020 includes a plurality of layers 430-433. The free layer 1026 is ferromagnetic. The free layer 1026 includes two layers, namely, a first layer 430 and a second layer 432, separated by a spacer layer 431. The barrier layer 433 of the free layer 1026 is disposed between the second layer 432 and the cap layer 428. The lower shield 402, the lower lead 406, the buffer layer 422, the AFM layer 424, the first layer 430, the third insulating layer 440, the first insulating layer 412, and the upper shield 404 each have a first width W1 in the stripe height direction from the MFS to the first surface 401 opposite the MFS.

[0096] The read head 1000 is similar to Figure 8 and 9 4. The embodiment of the present invention relates to read heads 800 and 900 of the present invention because each free layer 1026 of each read sensor 1020 shares a common first layer 430, while each read sensor 1020 has its own individual spacer layer 431, second layer 432, and barrier layer 433. In other words, each sensor 1020 includes a portion of the first layer 430, such that the common portion of the first layer 430 spans across multiple read sensors 1020. A second insulating layer 408 is disposed on the first layer 430 of the free layer 1026 and surrounds each of the read sensors 1020 in the downtrack direction.

[0097] In addition, similar to Figure 5 、 6In the read heads 500, 600, 800, and 900 of FIG. 1 , FIG. 2 , FIG. 3 , and FIG. 4 , the plurality of soft-bias side shields 410 are positioned adjacent only to a portion of the sensor 1020. Specifically, the plurality of soft-bias side shields 410 are positioned adjacent only to the spacer layer 431, the second layer 432, the barrier layer 433, and the cap layer 428. The second insulating layer 408 is positioned between the plurality of soft-bias side shields 410 and the spacer layer 431, the second layer 432, the barrier layer 433, and the cap layer 428. The plurality of hard-bias side shields 460 are still positioned adjacent to and in contact with the plurality of soft-bias side shields 410 in the cross-track direction. Both the plurality of soft-bias side shields 410 and the plurality of hard-bias side shields 460 have a tenth thickness T10 in the downtrack direction.

[0098] Read head 1000 and Figure 8 The read head 800 is different in that the seventh insulating layer 1072 is positioned between the first layer 430 and the third insulating layer 440 on the back side of the read head 1000 recessed from the MFS. The seventh insulating layer 1072 may include the same material as or a different material from the first insulating layer 412. Furthermore, the seventh insulating layer 1072 has a fifth width W5 in the stripe height direction and a twelfth thickness T12 in the downtrack direction. The second insulating layer 408, the soft bias side shield 410, and the hard bias side shield 460 each have a sixth width W6 in the stripe height direction. The fifth width W5 may be greater than or equal to the sixth width W6. The fifth width W5 and the sixth width W6 are collectively equal to the first width W1 of the lower shield 402, the lower lead 406, the buffer layer 422, the AFM layer 424, the first layer 430, the first insulating layer 412, the third insulating layer 440, and the upper shield 404. The twelfth thickness T12 is greater than or equal to the tenth thickness T10.

[0099] The lower shield 402, lower lead 406, third insulating layer 440, first layer 430, first insulating layer 412, and upper shield 404 each have a first length L1 in the cross-track direction. The spacer layer 431, second layer 432, barrier layer 433, cap layer 428, and upper lead 416 each have a second length L2 in the cross-track direction that is less than the first length L1. The plurality of soft-bias side shields 410 each have a third length L3 in the cross-track direction, and the plurality of hard-bias side shields 460 each have a fourth length L4 in the cross-track direction that is substantially equal to or greater than the third length L3. The fourth length L4 is less than the first length L1. The length of the second insulating layer 408 in the cross-track direction is substantially equal to the sum of the third length L3 and the fourth length L4.

[0100] The soft-bias side shields 410 help bias the magnetic read field of the read sensor 920 during magnetic read operations. The soft-bias side shields 410 promote a magnetic field in the cross-track direction during magnetic read operations. The plurality of hard-bias side shields 460 fix the magnetization of the soft-bias side shields 410 in a desired direction, such as the cross-track direction. The plurality of hard-bias side shields 460 stabilize the plurality of soft-bias side shields 410 to enhance magnetic read operations while minimizing signal shunting.

[0101] In addition, as mentioned above Figure 4C , the lower lead 406 has a third thickness T3. The first insulating layer 412, the third insulating layer 440, and the upper lead 416 between the upper shield 404 and the hard bias side shield 460 collectively have a fourth thickness T4. The fourth thickness T4 is substantially equal to the third thickness T3, such that the difference between the fourth thickness T4 and the third thickness T3 is approximately 50 nm or less. The fourth thickness T4 being substantially equal to the third thickness T3 facilitates stabilization of the read sensor 1020 by helping to stabilize the soft bias side shield 410, thereby enhancing magnetic read operation while minimizing signal shunting.

[0102] Figure 11 is a schematic isometric MFS view of a read head 1100 according to one embodiment. The read head 1100 may be used as Figure 1 A portion of a tape drive 100 (magnetic storage device) is shown in FIG. Figure 11 The read head 1100 is similar to Figures 4A to 4C Read head 400, Figures 4D to 4E Read head 490, Figure 5 Read head 500, Figure 6 The read head 600 and Figure 7 Read head 700, Figure 8 Read head 800, Figure 9 The read head 900 and Figure 10 Thus, for aspects that are the same in each of the read heads 400, 490, 500, 600, 700, 800, 900, 1000, 1100, Figures 4A to 10 and Figure 11 Similar reference numerals are used in the Figures 4A to 11 Each of the read heads 400 , 490 , 500 , 600 , 700 , 800 , 900 , 1000 , 1100 may be used in combination with one another.

[0103] although Figure 11 Three read sensors 1120 are shown in FIG, but the read head 1100 may include any number of read sensors 1120 and the number of read sensors 1120 is not intended to be limiting. Figure 11As shown in FIG, lower leads 406 are common to each read sensor 1120, while upper leads 416 are separate for each read sensor 1120. However, in some embodiments, each read sensor 1120 may have a separate lower lead 406 (not shown). In other embodiments, upper leads 416 may be common to each read sensor 1120.

[0104] Each read sensor 1120 in the plurality of read sensors 1120 includes a multilayer structure. The multilayer structure of each read sensor 1120 includes a buffer layer 422 disposed on the bottom lead 406, an AFM layer 424 disposed on the buffer layer 422, and a free layer 1126 disposed on the AFM layer 424. Each read sensor 420 includes a cap layer 428 disposed on the free layer 1126. The buffer layer 422 is disposed between the AFM layer 424 and the bottom lead 406. The cap layer 428 is non-ferromagnetic. The buffer layer 422 and the AFM layer 424 are common to each sensor 1120. In other words, each sensor 1120 includes a portion of the buffer layer 422 and a portion of the AFM layer 424, such that the common portion of the buffer layer 422 and the common portion of the AFM layer 424 are common across the plurality of read sensors 1010.

[0105] The free layer 1126 of each read sensor 1120 includes a plurality of layers 430-433. The free layer 1126 is ferromagnetic. The free layer 1126 includes two layers, namely, a first layer 430 and a second layer 432, separated by a spacer layer 431. The barrier layer 433 of the free layer 1126 is disposed between the second layer 432 and the cap layer 428. The lower shield 402, the lower lead 406, the third insulating layer 440, the first insulating layer 412, and the upper shield 404 each have a first width W1 in the stripe height direction from the MFS to the first surface 401 opposite the MFS.

[0106] The read head 1100 is similar to Figures 8 to 10 4. The embodiment of the present invention relates to read heads 800, 900, and 1000 of the present invention because each free layer 1126 of each read sensor 1120 shares a common first layer 430, while each read sensor 1120 has its own individual spacer layer 431, second layer 432, and barrier layer 433. In other words, each sensor 1120 includes a portion of the first layer 430 such that the common portion of the first layer 430 spans across multiple read sensors 1120. A second insulating layer 408 is disposed on the first layer 430 of the free layer 1126 and surrounds each of the read sensors 1120 in the downtrack direction.

[0107] In addition, similar to Figure 5 、 6In the read heads 500, 600, 800, 900, and 10 of FIG. 10 , the plurality of soft-bias side shields 410 are positioned adjacent only to a portion of the sensor 1120. Specifically, the plurality of soft-bias side shields 410 are positioned adjacent only to the spacer layer 431, the second layer 432, the barrier layer 433, and the cap layer 428. The second insulating layer 408 is positioned between the plurality of soft-bias side shields 410 and the spacer layer 431, the second layer 432, the barrier layer 433, and the cap layer 428. The plurality of hard-bias side shields 460 are still positioned adjacent to and in contact with the plurality of soft-bias side shields 410 in the cross-track direction. Both the plurality of soft-bias side shields 410 and the plurality of hard-bias side shields 460 have a tenth thickness T10 in the downtrack direction.

[0108] Read head 1100 and Figure 8 The read head 800 of FIG. 1 differs in that an eighth insulating layer 1174 is disposed between the lower lead 406 and the third insulating layer 440 on the back side of the read head 1100 recessed from the MFS. The eighth insulating layer 1174 may include the same material as or a different material from the first insulating layer 412. Furthermore, the eighth insulating layer 1174 has a fifth width W5 in the stripe height direction and a thirteenth thickness T13 in the downtrack direction. The thirteenth thickness T13 is greater than the tenth thickness T10. The buffer layer 422, the AFM layer 424, the first layer 430, the second insulating layer 408, the soft bias side shield 410, the hard bias side shield 460, and the sensor 1120 each have a sixth width W6 in the stripe height direction. The fifth width W5 may be greater than or equal to the sixth width W6. The fifth width W5 and the sixth width W6 are collectively equal to the first width W1 of the lower shield 402 , the lower lead 406 , the first insulating layer 412 , the third insulating layer 440 , and the upper shield 404 .

[0109] The lower shield 402, lower lead 406, third insulating layer 440, first layer 430, first insulating layer 412, and upper shield 404 each have a first length L1 in the cross-track direction. The spacer layer 431, second layer 432, barrier layer 433, cap layer 428, and upper lead 416 each have a second length L2 in the cross-track direction that is less than the first length L1. The plurality of soft-bias side shields 410 each have a third length L3 in the cross-track direction, and the plurality of hard-bias side shields 460 each have a fourth length L4 in the cross-track direction that is substantially equal to or greater than the third length L3. The fourth length L4 is less than the first length L1. The length of the second insulating layer 408 in the cross-track direction is substantially equal to the sum of the third length L3 and the fourth length L4.

[0110] The soft-bias side shields 410 help bias the magnetic read field of the read sensor 920 during magnetic read operations. The soft-bias side shields 410 promote a magnetic field in the cross-track direction during magnetic read operations. The plurality of hard-bias side shields 460 fix the magnetization of the soft-bias side shields 410 in a desired direction, such as the cross-track direction. The plurality of hard-bias side shields 460 stabilize the plurality of soft-bias side shields 410 to enhance magnetic read operations while minimizing signal shunting.

[0111] In addition, as mentioned above Figure 4C , the lower lead 406 has a third thickness T3. The first insulating layer 412, the third insulating layer 440, and the upper lead 416 between the upper shield 404 and the hard bias side shield 460 collectively have a fourth thickness T4. The fourth thickness T4 is substantially equal to the third thickness T3, such that the difference between the fourth thickness T4 and the third thickness T3 is approximately 50 nm or less. The fourth thickness T4 being substantially equal to the third thickness T3 facilitates stabilization of the read sensor 1120 by helping to stabilize the soft bias side shield 410, thereby enhancing magnetic read operation while minimizing signal shunting.

[0112] Thus, stabilizing soft-bias side shields positioned between and outside of multiple read sensors in a read head using hard-bias side shields helps bias the magnetic read field of the read sensors during magnetic read operations. Thus, the stabilized soft-bias shields initiate a magnetic field in a cross-track direction during magnetic read operations while minimizing signal shunting, thereby resulting in improved magnetic read operations in the read head.

[0113] In one embodiment, a read head includes: a lower shield; an upper shield; one or more lower leads disposed above the lower shield; one or more upper leads disposed between the one or more lower leads and the upper shield; a plurality of read sensors disposed between the one or more lower leads and the one or more upper leads at a medium-facing surface, each of the plurality of read sensors comprising a multi-layer structure; a plurality of soft bias side shields disposed between and outside the plurality of read sensors; and a plurality of hard bias side shields disposed on and in contact with the plurality of soft bias side shields.

[0114] The plurality of soft bias side shields have a first width in the stripe height direction, and the lower shield has a second width in the stripe height direction that is greater than the first width. The plurality of soft bias side shields have a first width in the stripe height direction, and the lower shield has a second width in the stripe height direction that is substantially equal to the first width. The plurality of soft bias side shields have a first thickness in the downtrack direction, and the plurality of hard bias side shields have a second thickness in the downtrack direction that is different from or substantially equal to the first thickness. The read head further includes a non-magnetic layer disposed between the one or more lower leads and the plurality of soft bias side shields. The non-magnetic layer is disposed between the plurality of soft bias side shields and the first insulating layer and is in contact with the plurality of soft bias side shields and the first insulating layer. The magnetic storage device includes a read head.

[0115] In another embodiment, a read head includes: a lower shield; a lower lead disposed above the lower shield; an antiferromagnetic (AFM) layer disposed above the lower lead; a first layer disposed on the AFM layer; and a plurality of read sensors disposed above the first layer at a media facing surface (MFS), each of the plurality of read sensors comprising a multilayer structure including a portion of the AFM layer and a portion of the first layer. The read head further includes: a plurality of soft-bias side shields disposed between and outside the plurality of read sensors; a plurality of hard-bias side shields disposed in contact with the plurality of soft-bias side shields; one or more upper leads disposed above the plurality of read sensors; and an upper shield disposed above the one or more upper leads.

[0116] The AFM layer and the first layer each have a first width in the stripe height direction. The plurality of soft bias side shields and the plurality of hard bias side shields each have a second width in the stripe height direction. The first width is substantially equal to the second width. The first width is greater than the second width. The first width is less than the second width. The multilayer structure further includes a buffer layer, a second layer disposed above the buffer layer, a barrier layer disposed above the second layer, and a cap layer disposed above the barrier layer. The plurality of soft bias side shields are disposed adjacent to and outside the second layer, the barrier layer, and the cap layer. The magnetic storage device includes a read head.

[0117] In yet another embodiment, a read head includes: a lower shield; an upper shield; one or more lower leads disposed above the lower shield; one or more upper leads disposed between the one or more lower leads and the upper shield; and a plurality of read sensors disposed between the one or more lower leads and the one or more upper leads at a media-facing surface, wherein each of the plurality of read sensors includes a multilayer structure comprising: a buffer layer; an AFM layer disposed above the buffer layer; a free layer disposed above the AFM layer, the free layer including a first layer and a second layer; a barrier layer disposed above the free layer; and a cap layer disposed above the barrier layer. The read head further includes: a plurality of soft-bias side shields disposed adjacent to and outside the second layer, the barrier layer, and the cap layer of each read sensor; and a plurality of hard-bias side shields disposed on and in contact with the plurality of soft-bias side shields.

[0118] The read head further includes a non-magnetic layer positioned between one or more lower leads and the plurality of soft-bias side shields, and between one or more lower leads and the plurality of hard-bias side shields. The non-magnetic layer is positioned adjacent to and external to the buffer layer, the AFM layer, and the first layer of each read sensor. The plurality of hard-bias side shields have a first thickness in the downtrack direction, and the non-magnetic layer has a second thickness in the downtrack direction that is different from or substantially equal to the first thickness. The plurality of hard-bias side shields have a first width in the stripe height direction, and the non-magnetic layer has a second width in the stripe height direction that is greater than or substantially equal to the first width. The magnetic storage device includes a read head.

[0119] While the foregoing is directed to embodiments of the present disclosure, other and further embodiments of the disclosure may be devised without departing from the basic scope thereof, the scope of which is determined by the claims that follow.

Claims

1. A magnetic read head comprising: lower shield; upper shield; one or more lower leads disposed above the lower shield; one or more upper leads disposed between the one or more lower leads and the upper shield; a plurality of read sensors disposed between the one or more lower leads and the one or more upper leads at a media-facing surface, each read sensor of the plurality of read sensors comprising a multi-layer structure; a plurality of soft-biased side shields positioned between and outside the plurality of read sensors; a plurality of hard-biased side shields disposed on and in contact with the plurality of soft-biased side shields; as well as A nonmagnetic layer is disposed between the one or more lower leads and the plurality of soft bias side shields. 2 . The read head of claim 1 , wherein the plurality of soft bias side shields have a first width in a stripe height direction, and the lower shield has a second width in the stripe height direction that is greater than the first width. 3 . The read head of claim 1 , wherein the plurality of soft bias side shields have a first width in a stripe height direction, and the lower shield has a second width in the stripe height direction that is substantially equal to the first width.

4. The read head of claim 1 , wherein the plurality of soft bias side shields have a first thickness in a downtrack direction, and the plurality of hard bias side shields have a second thickness in the downtrack direction, the second thickness being different from or substantially equal to the first thickness. 5 . The read head of claim 1 , wherein the nonmagnetic layer is disposed between and in contact with the plurality of soft bias side shields and a first insulating layer. 6 . A magnetic storage device comprising the read head according to claim 1 .

7. A magnetic read head comprising: lower shield; a lower lead disposed above the lower shield; a plurality of read sensors disposed over the lower lead at a media facing surface (MFS), each read sensor of the plurality of read sensors comprising a multi-layer structure comprising: a portion of the buffer layer disposed on the lower lead; and an antiferromagnetic layer, i.e., a portion of an AFM layer, disposed on the buffer layer; a plurality of soft-biased side shields positioned between and outside the plurality of read sensors; a plurality of hard-biased side shields positioned in contact with the plurality of soft-biased side shields; one or more upper leads positioned above the plurality of read sensors; and An upper shield is positioned over the one or more upper leads.

8. The read head of claim 7, wherein the AFM layer and the first layer each have a first width in a stripe height direction, and wherein the plurality of soft bias side shields and the plurality of hard bias side shields each have a second width in the stripe height direction.

9. The read head of claim 8, wherein the first width is substantially equal to the second width.

10. The read head of claim 8, wherein the first width is greater than the second width. The read head of claim 8 , wherein the first width is smaller than the second width.

12. The read head of claim 7, wherein the multi-layer structure further comprises: a free layer disposed above the AFM layer; a barrier layer disposed over the free layer; as well as A top cover layer is disposed over the barrier layer, wherein the plurality of soft biasing side shields are disposed adjacent to and outside of the second layer, the barrier layer, and the top cover layer.

13. A magnetic storage device comprising the read head according to claim 7.

14. A magnetic read head comprising: lower shield; upper shield; one or more lower leads disposed above the lower shield; one or more upper leads disposed between the one or more lower leads and the upper shield; a plurality of read sensors disposed between the one or more lower leads and the one or more upper leads at a media-facing surface, each read sensor of the plurality of read sensors comprising a multi-layer structure comprising: buffer layer; an antiferromagnetic layer, namely an AFM layer, disposed above the buffer layer; a free layer disposed above the AFM layer, the free layer comprising a first layer and a second layer; a barrier layer disposed over the free layer; and a top cover layer disposed above the barrier layer; a plurality of soft biased side shields positioned adjacent and external to the second layer, the barrier layer, and the cap layer of each read sensor; and A plurality of hard-biased side shields are disposed on and in contact with the plurality of soft-biased side shields.

15. The read head of claim 14, further comprising a nonmagnetic layer disposed between the one or more lower leads and the plurality of soft bias side shields and between the one or more lower leads and the plurality of hard bias side shields.

16. The read head of claim 15, wherein the nonmagnetic layer is disposed adjacent to and outside the buffer layer, the AFM layer, and the first layer of each read sensor. 17 . The read head of claim 15 , wherein the plurality of hard bias side shields have a first thickness in a downtrack direction, and the nonmagnetic layer has a second thickness in the downtrack direction that is different from or substantially equal to the first thickness.

18. The read head of claim 17, wherein the plurality of hard bias side shields have a first width in a stripe height direction, and the nonmagnetic layer has a second width in the stripe height direction that is greater than or substantially equal to the first width.

19. A magnetic storage device comprising the read head according to claim 14.

20. A magnetic read head comprising: lower shield; upper shield; one or more lower leads disposed above the lower shield; one or more upper leads disposed between the one or more lower leads and the upper shield; a plurality of read sensors disposed between the one or more lower leads and the one or more upper leads at a media-facing surface, each read sensor of the plurality of read sensors comprising a multi-layer structure; a plurality of soft-biased side shields disposed between and outside the plurality of read sensors, wherein the plurality of soft-biased side shields have a first width in a stripe height direction and the lower shield has a second width in the stripe height direction that is greater than the first width; as well as A plurality of hard-biased side shields are disposed on and in contact with the plurality of soft-biased side shields.

21. The read head of claim 20, wherein the plurality of soft bias side shields have a first thickness in a downtrack direction, and the plurality of hard bias side shields have a second thickness in the downtrack direction, the second thickness being different from or substantially equal to the first thickness.

22. The read head of claim 20, further comprising a non-magnetic layer disposed between the one or more lower leads and the plurality of soft bias side shields. 23 . The read head of claim 22 , wherein the nonmagnetic layer is disposed between and in contact with the plurality of soft bias side shields and a first insulating layer.

24. The read head of claim 22, wherein the plurality of hard bias side shields have a first thickness in a downtrack direction, and the nonmagnetic layer has a second thickness in the downtrack direction that is different from or substantially equal to the first thickness.

25. The read head of claim 22, wherein the plurality of hard bias side shields have a first width in a stripe height direction, and the nonmagnetic layer has a second width in the stripe height direction that is greater than or substantially equal to the first width.

26. A magnetic storage device comprising the read head according to claim 20.

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