G11B5/3932

Magnetic sensor

A magnetic sensor whose output characteristic is less sensitive to the environmental temperature is provided. Magnetic sensor 1 has free layer 24 whose magnetization direction changes in response to an external magnetic field, pinned layer 22 whose magnetization direction is fixed with respect to the external magnetic field, spacer layer 23 that is located between pinned layer 22 and free layer 24 and that exhibits a magnetoresistance effect, and at least one magnet film 25 that applies a bias magnetic field to free layer 24. The film thickness of the magnet film is 15 nm or more and 50 nm or less. The relationship of 0.7≤T.sub.C_HM/T.sub.C_FL≤1.05 is satisfied, where T.sub.C_HM is Curie temperature of the magnet film, and T.sub.C_FL is Curie temperature of the free layer.

Coupled Soft Bias Scissor Type Sensor
20180005652 · 2018-01-04 ·

A magnetic read head is provided, comprising a bottom magnetic shield, a first free magnetic layer, a second free magnetic layer, and a top magnetic shield, arranged from bottom to top in this order in a stacking direction from a leading side to a trailing side of the read head. A non-soft bias layer is positioned below the top magnetic shield and on a back side of the first and the second free magnetic layers. The top magnetic shield has a unidirectional anisotropy, the magnetic moments of the top and the bottom magnetic shields are canted relative to a plane of the first and the second free magnetic layers, and the top and the bottom magnetic shields are decoupled from the non-soft bias layer and not magnetically coupled to a soft bias layer.

Longitudinal Sensor Bias Structures and Method of Formation Thereof

The present disclosure generally relates to a storage device comprising soft bias structures having high coercivity and high anisotropy, and a method of forming thereof. The soft bias structures may be formed by moving a wafer in a first direction under a plume of NiFe to deposit a first NiFe layer at a first angle, moving the wafer in a second direction anti-parallel to the first direction to deposit a second NiFe layer at a second angle on the first NiFe layer, and repeating one or more times. The soft bias structures may be formed by rotating a wafer to a first position, depositing a first NiFe layer at a first angle, rotating the wafer to a second position, depositing a second NiFe layer at a second angle on the first NiFe layer, and repeating one or more times. The first and second NiFe layers have different grain structures.

Magnetic read sensors having stabilized upper readers, and related methods

Aspects of the present disclosure generally relate to magnetic recording heads of magnetic recording devices. A read head includes a first reader, an insulating separation layer, and a second reader disposed above the insulating separation layer. The second reader includes a magnetic seed layer and a cap layer. The second reader includes a first upper free layer disposed between the magnetic seed layer and the cap layer, and a second upper free layer disposed between the first upper free layer and the cap layer. The second reader includes a barrier layer. In one implementation the second reader includes an antiferromagnetic (AFM) layer disposed between the magnetic seed layer and the insulating separation layer to pin the magnetic seed layer.

Soft bias shape anisotropy stabilization read head design and method of making same

The present disclosure generally relates to magnetic storage devices, such as magnetic tape drives, comprising a read head. The read head comprises a plurality of read sensors disposed between a lower shield having a first width in a stripe height direction and an upper shield. The plurality of read sensors comprise an antiferromagnetic layer and a free layer comprising a first layer and a second layer. A plurality of soft bias side shields disposed adjacent to and outwardly of the plurality of read sensors in a cross-track direction, each of the plurality of soft bias side shields having a second width in the stripe height direction less than the first width. Each of the plurality of soft bias side shields are spaced a first distance from the lower shield and a second distance from the upper shield, the first distance being substantially equal to the second distance.

Method to enhance magnetic strength and robustness of rear hard bias for dual free layer read

The present disclosure generally relates to read heads having dual free layer (DFL) sensors. The read head has a sensor disposed between two shields. The sensor is a DFL sensor and has a surface at the media facing surface (MFS). Recessed from the DFL sensor, and from the MFS, is a rear hard bias (RHB) structure. The RHB structure is disposed between the shields as well. In between the DFL sensor and the RHB structure is insulating material. The RHB is disposed on the insulating material. The RHB includes a RHB seed layer as well as a RHB bulk layer. The RHB bulk layer includes a first bulk layer and a second bulk layer, the first bulk layer having a different density relative to the second bulk layer.

Read head having one or more antiferromagnetic layers below soft bias side shields, and related methods

The present disclosure relates to read head apparatus, and methods of forming read head apparatus, for magnetic storage devices, such as magnetic tape drives (e.g., tape drives). In one implementation, a read head for magnetic storage devices includes a lower shield, an upper shield, one or more lower leads, and a plurality of upper leads. The read head includes a plurality of read sensors, each read sensor of the plurality of read sensors including a first antiferromagnetic (AFM) layer. The read head includes a plurality of soft bias side shields disposed between and outwardly of the plurality of read sensors. The read head includes a plurality of second AFM layers disposed below the plurality of soft bias side shields along a downtrack direction.

Planar design for sensors in a dual free layer read head

The present disclosure generally relates to a dual free layer (DFL) two dimensional magnetic recording (TDMR) read head. The read head comprises a first sensor, a first rear hard bias (RHB) structure disposed adjacent to the first sensor, an upper shield disposed over the first sensor and first RHB structure, a lower shield disposed over the upper shield, a second sensor disposed over the lower shield, and a second RHB structure disposed adjacent to the second sensor. A first surface of the first sensor is substantially flush or aligned with a first surface of the first RHB structure. A first surface of the second sensor is substantially flush or aligned with a first surface of the second RHB structure. The upper shield extends linearly from a media facing surface into the read head. The first lower shield is over-milled a greater amount of time than the second lower shield.

Soft bias side shield stabilized by hard bias for read head design

The present disclosure generally relates to magnetic storage devices, such as magnetic tape drives, comprising a read head. The read head comprises 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 outwardly of 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 are spaced a first distance from the lower shield and each of the hard bias side shields are spaced a second distance from the upper shield, the first distance being substantially equal to the second distance.

Reader noise reduction using spin hall effects
11587582 · 2023-02-21 · ·

A read head is disclosed wherein a Spin Hall Effect (SHE) layer is formed on a free layer (FL) in a sensor and between the FL and top shield (S2). Preferably, the sensor has a seed layer, an AP2 reference layer, antiferromagnetic coupling layer, AP1 reference layer, and a tunnel barrier sequentially formed on a bottom shield (S1). In a three terminal configuration, a first current flows between S1 and S2 such that the AP1 reference layer produces a first spin torque on the FL, and a second current flows across the SHE layer thereby generating a second spin torque on the FL that opposes the first spin torque. When the stripe heights of the FL and SHE layer are equal, a two terminal configuration is employed where a current flows between one side of the SHE layer to a center portion thereof and then to S1, or vice versa.