摘要:
An in-line lapping guide uses a contiguous resistor in a cavity to separate a lithographically-defined sensor from the in-line lapping guide. As lapping proceeds through the cavity toward the sensor, the resistance across the sensor leads increases to a specific target, thereby indicating proximity to the sensor itself. The contiguous resistor is fabricated electrically in parallel to the sensor and the in-line lapping guide. The total resistance across the sensor leads show resistance change even when lapping through the cavity portion. One method to produce the contiguous resistor is to partial mill the cavity between the sensor and the in-line lapping guide so that a film of metal is left. Total resistance across leads is the parallel resistance of the sensor, the contiguous resistor, and the in-line lapping guide.
摘要:
An in-line lapping guide uses a contiguous resistor in a cavity to separate a lithographically-defined sensor from the in-line lapping guide. As lapping proceeds through the cavity toward the sensor, the resistance across the sensor leads increases to a specific target, thereby indicating proximity to the sensor itself. The contiguous resistor is fabricated electrically in parallel to the sensor and the in-line lapping guide. The total resistance across the sensor leads show resistance change even when lapping through the cavity portion. One method to produce the contiguous resistor is to partial mill the cavity between the sensor and the in-line lapping guide so that a film of metal is left. Total resistance across leads is the parallel resistance of the sensor, the contiguous resistor, and the in-line lapping guide.
摘要:
A method of forming an embedded read element is used in the fabrication process of a magnetic head assembly including write and read heads. In this method, three photolithographic patterning steps are applied for defining the designed height of the embedded read element, defining its designed width, and connecting it with conducting layers, respectively. An in-line lapping guide is also formed with a spacing in front of the embedded read element. In this method, two mechanical lapping steps are applied, one monitored by measuring the resistance of a parallel circuit of the embedded read element and the in-line lapping guide, and the other monitored by measuring the GMR response of the embedded read element.
摘要:
One illustrative method of fabricating a read sensor of a magnetic head includes the steps of forming a plurality of read sensor layers on a wafer; etching the read sensor layers to form a read sensor structure with a trench in front of the read sensor structure; forming a highly porous material within the trench; and slicing the wafer and lapping the sliced wafer through the highly porous material until an air bearing surface (ABS) of the magnetic head is reached. Advantageously, the highly porous material in front of the read sensor structure reduces mechanical stress on the read sensor during the lapping process. This reduces the likelihood that the amplitude of the read sensor will be degraded or set in a “flipped” or reversed orientation, as well as reduces the likelihood that electrostatic discharge (ESD) damage to the read sensor will occur.
摘要:
A method for making a magnetoresistive read head so that the pinned ferromagnetic layer is wider than the stripe height of the free ferromagnetic layer uses ion milling with the ion beam aligned at an angle to the substrate supporting the stack of layers making up the read head. The stack is patterned with photoresist to define a rectangular region with front and back long edges aligned parallel to the read head track width. After ion milling in two opposite directions orthogonal to the front and back long edges, the pinned layer width has an extension. The extension makes the width of the pinned layer greater than the stripe height of the free layer after the substrate and stack of layers are lapped. The length of the extension is determined by the angle between the substrate and the ion beam and the thickness of the photoresist.
摘要:
A magnetic sensor is provided, having two bias layers separated by a decoupling layer to eliminate exchange coupling between the bias layers. The two bias layers may have differing coercivities, such that the biases provided by the bias layers to the free layer are independently adjustable. The grain structures of the two bias layers may be substantially decorrelated by the decoupling layer.
摘要:
A read head has a bottom lead made of material that is relatively polish resistant and a top lead layer that polishes down more easily than the bottom layer. With this structure, when the layers are deposited and then polished down, the top layer recesses away from the sensor (and bottom lead layer) in a controlled fashion, providing an acceptable lead structure that reduces the mismatch between the read head physical read width and magnetic read width.
摘要:
A method of making a read sensor while protecting it from electrostatic discharge (ESD) damage involves forming a severable shunt during the formation of the read sensor. The method may include forming a resist layer over a plurality of read sensor layers; performing lithography with use of a mask to form the resist layer into a patterned resist which exposes left and right side regions over the read sensor layers as well as a shunt region; etching, with the patterned resist in place, to remove materials in the left and right side regions and in the shunt region; and depositing, with the patterned resist in place, left and right hard bias and lead layers in the left and right side regions, respectively, and in the shunt region for forming a severable shunt which electrically couples the left and right hard bias and lead layers together for ESD protection.
摘要:
A lead overlay design of a magnetic sensor is described with sensor and free layer dimensions such that the free layer is stabilized by the large demagnetization field due to the shape anisotropy. In one embodiment the giant magnetoresistive (GMR) effect under the leads is destroyed by removing the antiferromagnetic (AFM) and pinned layers above the free layer. The overlaid lead pads are deposited on the exposed spacer layer at the sides of the mask that defines the active region. In other embodiment a layer of electrically insulating material is deposited over the sensor to encapsulate it and thereby insulate it from contact with the hardbias structures. Various embodiments with self-aligned leads are also described. In a variation of the encapsulation embodiment, the insulating material is also deposited under the lead pads so the electrical current is channeled through the active region of the sensor and sidewall deposited lead pads.
摘要:
A lead overlay design of a magnetic sensor is described with sensor and free layer dimensions such that the free layer is stabilized by the large demagnetization field due to the shape anisotropy. In one embodiment the giant magnetoresistive (GMR) effect under the leads is destroyed by removing the antiferromagnetic (AFM) and pinned layers above the free layer. The overlaid lead pads are deposited on the exposed spacer layer at the sides of the mask that defines the active region. In other embodiment a layer of electrically insulating material is deposited over the sensor to encapsulate it and thereby insulate it from contact with the hardbias structures. Various embodiments with self-aligned leads are also described. In a variation of the encapsulation embodiment, the insulating material is also deposited under the lead pads so the electrical current is channeled through the active region of the sensor and sidewall deposited lead pads.