Abstract: The present invention is directed to the fabrication of head sliders for use in hard disk drives, and in particular the provision and usage of electrical bond pads on the slider surface structure to accommodate needs of the fabrication process as well as slider operation within a disk drive.

Abstract: According to one embodiment, a recording head includes a main pole and a first shield. The first shield includes a distal end portion projecting from an air bearing surface of a slider. The distal end portion includes a distal end surface which includes a first shield edge opposing the main pole with a write gap and a second shield edge spaced apart from the first shield edge in a trailing end side. A distal end portion of the main pole projects from the distal end surface. When a length between the distal end portion of the main pole and the second shield edge is L1, the projection amount of the distal end portion of the main pole is h2, a flying pitch is D1, and a protrusion pitch angle is D2, the recording head satisfies a relationship of: L1?h2/(D1+D2).

Abstract: A row bar for forming magnetic heads includes a row of magnetic head forming portions each having a magnetic head and a cutting portion adjacent to the magnetic heads. A row of bonding pads and a first ELG pad are provided at the magnetic head, a second ELG pad is provided at the cutting portion, both of the first and the second ELG pads are adapted for contacting with a probe during lapping process, and a conductive structure that is higher than surfaces of the first and the second ELG pads is formed at peripheries of the first and the second ELG pads respectively. Due to the conductive structures, a probe used in lapping process will be prevented from shifting from the ELG pads to ensure a stable contact, thereby obtaining efficient and accurate resistance measurement.

Abstract: An apparatus, according to one embodiment, includes a first circuit comprising a pair of terminals coupled to a first read transducer having a tunnel valve structure and a first parallel circuit. A second circuit has a pair of terminals that are coupled to a second read transducer having a tunnel valve structure. An area of a tunnel barrier portion of the second read transducer is larger than an area of a tunnel barrier portion of the first read transducer. The terminal resistance of the first circuit is less than about five times a terminal resistance of the second circuit.

Abstract: A tape head writer yoke pole tip and a substrate ground plane are electrically coupled to the resistance measuring module. An electrically conductive wear layer is disposed over the pole tip and a ground plane at the tape bearing surface, forming a closed circuit. A magnetic tape is transported across the tape head and wears away the wear layer. The resistance measuring module identifies when the circuit becomes open, and an amount of tape travel until the open circuit occurred, and transmits this to a host computer for determination of a tape abrasivity measure as a function of the amount of tape travel. The write element can be used for write operations while the wear layer is present, and after the wear layer has been worn away.

Abstract: Electrostatic discharge protection can be afforded to a data recording head in accordance with various embodiments. A data recording head may consist of a circuit having a preamp ground connected to a ground substrate via a ground trace. The ground trace can consist of a first leg connected to the ground substrate and a second leg with an open connection extending from a dice line.

Abstract: Embodiments of the present invention relate to wear measurement. A system according to one embodiment includes a transport mechanism for running a tape across a wear structure and a measuring device for optically measuring an extent of wear of the wear structure. A method according to one embodiment includes positioning a tape across a wear structure, optically determining a first position of a back of the tape relative to a measuring device using the measuring device, running the tape across the wear structure for a period of time, optically determining a second position of the back of the tape relative to the measuring device using the measuring device after the period of time, and determining a difference between the first and second positions.

Abstract: Structures and methods are disclosed for parallel biasing and testing, at dc and high frequency, of two or more read heads within a two dimensional magnetic recording (TDMR) slider. Testing of heads comprises both conventional tests of the individual heads within the slider, as well as tests for interactions between the heads which are very closely spaced within the slider and thus may exhibit various magnetic, capacitive, ohmic, and stress-related interactions not seen in non-TDMR heads having only a single read head. Overall testing times are nearly the same as for single head testing.

Abstract: A device and associated method of use can have at least an object with a work surface that contacts a lapping surface of a tool. Topography of the lapping surface can be mapped in-situ by an adjacent sensor array and the topography stored in a memory. The sensor array may be configured with a plurality of sensors positioned on opposite sides of the object.

Abstract: A data storage device is disclosed comprising a first disk surface, a first head, and a first microactuator configured to actuate the first head over the first disk surface. The first microactuator is configured into a first sensor, and a first load operation is executed to load the first head over the first disk surface. A fly height instability of the first head is detected during the first load operation based on a first sensor signal generated by the first microactuator.

Abstract: A method for determining a critical dimension of a structure along a plane of interest from a measurement along a test plane that is not necessarily located at the plane of interest. The method involves slicing a structure along a test plane and measuring a marker feature in this test plane. A determination of a critical dimension of a feature at the plane of interest is then determined based on the measurement of the marker feature measurement at the test plane. This testing methodology can be useful, for example in the measurement of a critical dimension of a write pole at an air bearing surface plane form a measurement of a test feature at a plane that is not necessarily located at the air bearing surface plane.

Abstract: A novel method for manufacturing embedded a capacitive stack and a novel capacitive stack apparatus are provided having a capacitive core that serves as a structural substrate on which alternating thin conductive foils and nanopowder-loaded dielectric layers may be added and tested for reliability. This layering and testing allows early fault detection of the thin dielectric layers of the capacitive stack. The capacitive stack may be configured to supply multiple isolated capacitive elements that provide segregated, device-specific decoupling capacitance to one or more electrical components. The capacitive stack may serve as a core substrate on which a plurality of additional signaling layers of a multilayer circuit board may be coupled.

Abstract: The method according to the present invention includes the steps of: sequentially applying a plurality of different voltages to an MR element and sequentially detecting output signals from the MR element; and eliminating the MR element as a defective product when an evaluation value, based on a difference of SN ratios of the output signals from the MR element respectively obtained for each applied voltage, is less than a threshold value, and selecting the MR element as a non-defective product when the evaluation value is greater than or equal to the threshold value.

Abstract: A disc drive disc stack assembly and a method for forming the disc stack assembly to reduce servo pattern runout. The disc stack assembly includes a number of prewritten discs having a servo pattern and a disc alignment mark. The first step is to place a first disc about a spindle motor hub of the disc drive. The second step is to align a disc alignment mark of the first disc in relation to a direction of a biasing force. The third step is to apply the biasing force to the first disc to engage the first disc against the spindle motor hub. The fourth step is to repeat the first three steps for each remaining disc in the disc stack assembly. The final step is to clamp the prewritten discs with a disc clamp to secure the position of each prewritten disc relative to the spindle motor hub.

Abstract: A disk drive is assembled to have a cover that includes a hole therethrough, and an annular gasket continuously encircling the hole and being adhered to an undersurface of the disk drive cover. A breather filter is adjacent the disk drive base. The breather filter includes a breather filter housing having a top surface and an entrance port. The annular gasket is in compressive contact with, but not adhered to, the top surface of the breather filter housing. The annular gasket encircles the entrance port. In certain embodiments, this method of assembly may facilitate disk drive rework.

Abstract: A method of providing electrostatic discharge (ESD) protection for a read element in a magnetic storage system comprises coupling a first terminal of a shunting device to a first terminal of the read element; coupling a second terminal of the shunting device to a second terminal of the read element; providing a conductive path between the first and second terminals of the shunting device when the read element is disabled; and providing a nonconductive path between the first and second terminals of the shunting device when the read element is enabled.

Abstract: A space transformer for a semiconductor test probe card and method of fabrication. The method may include depositing a first metal layer as a ground plane on a space transformer substrate having a plurality of first contact test pads defining a first pitch spacing, depositing a first dielectric layer on the ground plane, forming a plurality of second test contacts defining a second pitch spacing different than the first pitch spacing, and forming a plurality of redistribution leads on the first dielectric layer to electrically couple the first contact test pads to the second contact test pads. In some embodiments, the redistribution leads may be built directly on the space transformer substrate. The method may be used in one embodiment to remanufacture an existing space transformer to produce fine pitch test pads having a pitch spacing smaller than the original test pads.

Abstract: A method for modeling devices in a wafer comprises the step of providing the wafer comprising a first plurality of devices having a track width and a first stripe height, a second plurality of devices having the track width and a second stripe height, and a third plurality of devices having the track width and a third stripe height. The method further comprises the steps of measuring resistance values for the first, second and third plurality of devices to obtain a data set correlating a stripe height and a resistance value for each of the first, second and third plurality of devices, and estimating a linear relationship between resistance and inverse stripe height for the first, second and third plurality of devices based on the data set.

Abstract: In a manufacturing process of a head slider, a plurality of head elements are formed on a wafer, each head element comprising: a return pole, a coil, and a main pole. The wafer is cut into respective head elements so that individual head sliders are formed. A ratio of an amplitude of an electrical signal applied to the coil of the write head on the head slider to an amplitude of output from an independent magnetic field sensor not embedded in the head slider is calculated, where the independent magnetic field sensor is disposed near the main pole so as to be opposed to the main pole across the air bearing surface, and where the ratio is calculated while a displacement between the main pole and the magnetic field sensor is swept. A flare point height of the main pole is determined from the calculated amplitude ratio.

Abstract: A method and system for providing an energy assisted magnetic recording (EAMR) head are described. The EAMR head includes a laser, a slider, and an EAMR transducer. The laser has a main emitter and at least one alignment emitter. The slider includes at least one alignment waveguide, at least one output device, and an air-bearing surface (ABS). The alignment waveguide(s) are aligned with the alignment emitter(s). The EAMR transducer is coupled with the slider and includes a waveguide aligned with main emitter. The waveguide is for directing energy from the main emitter toward the ABS.

Abstract: A method for a slider pad that allows for contact to be mitigated without plastic deformation. Various embodiments of the present disclosure are generally directed to a slider that presents a transducer and has at least one air bearing surface (ABS) feature. The ABS feature comprises a pair of sidewalls spaced a distance X apart. A pad is deposited on the ABS feature so that the pad comprises a hemispherical cross-section and has a circumferential diameter greater than X. As configured, the pad may mitigate contact between the pad and a media surface with elastic deformation.

Abstract: A process tray for head stack assembly includes a main tray and at least one jig. Each jig has a main body with one set of locating holes formed thereon and two elastic arms respectively extending from two sides of the main body for providing force to hold the head stack assembly. The main tray has a main frame and a supporting frame disposed within and connected to the main frame for supporting the jig and/or the head stack assembly. The supporting frame has at least one set of locating bumps formed thereon for locating at least one jig on the main tray by respectively inserting the locating bumps into the locating holes formed on the jig. The process tray of the present invention can carry the head stack assembly during the whole head stack assembly manufacturing process, thereby simplifying the HSA manufacturing process, increasing productive efficiency and reducing the cost.

Abstract: A method for providing an electronic lapping guide (ELG) for a structure in a magnetic transducer are described. The structure has a front edge and a back edge. The ELG includes a stripe having a top edge and a bottom edge. The method includes calibrating a sheet resistance of the stripe and calibrating an offset of the top edge of the stripe from the back edge of the structure. The method further includes terminating the lapping based at least on the sheet resistance and offset of the ELG.

Abstract: Methods of lapping rows of recording heads are described after an air bearing surface (ABS) damascene process is performed. The ABS damascene process uses a selective etching process to form voids in the row of recording heads where conductive material forms a feature in the recording head, such as a wrap around shield. The conductive material is then deposited on the ABS of the row to fill the voids, and the row is lapped. According to methods provided herein, the resistance of one or more lapping guides in the row of recording heads is monitored to determine when the conductive material is removed by the lapping process. When the monitored resistance indicates that the conductive material is removed, the lapping process is stopped. The resistance across one or more lapping guides may also be used to control the lapping process to uniformly lap the conductive material from the ABS.

Abstract: A method for manufacturing a magnetic head for magnetic data recording, that allows a lapping termination point to be easily and accurately determined during lapping. The method includes constructing a lapping guide that has an electrically is formed to provide an abrupt change in resistance at a point where lapping should be terminated. This point of abrupt resistance change is located relative to the flare point of the write pole that the distance between the flare point and the air bearing surface can be accurately maintained. This abrupt resistance change also makes it possible to monitor both a stripe height defining rough lapping and an angled kiss lapping process using a single measurement channel.

Abstract: A defect inspection is performed for each of glass substrates by a surface defect detector. The distance from the center of the glass substrate to a detected defect, as a radius of a nonmagnetic region to be formed circular, is recorded along with an ID assigned to the glass substrate. Such defect information is recorded in a defect list using a printer or recorded in an RFID tag using an RFID writer. The defect list or the RFID tag is attached to a glass-substrate case. Each glass substrate and its defect information are in one-to-one correspondence and are provided to a customer as a magnetic disk manufacturer. Based on the obtained defect information, the customer manufactures magnetic disks each being a discrete track recording medium having the nonmagnetic region formed at the position where the defect is present.

Abstract: A head gimbal assembly (HGA) connector pad alignment jig is disclosed. One embodiment provides an HGA testing jig for holding an HGA, the HGA testing jig including an opening at a location of the HGA connector pads. In addition, an HGA testing apparatus including a disk for testing the HGA and a controller with a plurality of pin connectors for providing control information to the HGA during a testing process. Thus, the present technology provides an alignment adjuster for adjusting the location of the pin connectors with respect to the connector pads to ensure a good electrical connection between the HGA connector pads and the pin connectors.

Abstract: A method for manufacturing a magnetic write head for perpendicular magnetic recording. The method provides for accurate definition of a device feature such as a write pole flare point. A functional lapping guide is formed to determine when a lapping operation should be terminated to define an air bearing surface of a slider. In order to provide accurate compensation for manufacturing variations in the functional lapping guide, a dummy lapping guide is provided. An amount of variation of a front edge of the dummy lapping guide, which is defined by the same process step as a writer pole flare point, can be calculated by measuring the width (stripe height) of the dummy lapping guide based on its electrical resistance.

Abstract: A step portion for mounting a row bar is provided at a table stepping down from the face of the table, and by lowering a pair of hooks crossing over the step portion in its width direction, a row bar held by the hooks is mounted on the step portion. While interposing the row bar mounted on the step portion between a pair of hooks and a side face of the step portion, the side in longitudinal direction of the row bar and the bottom face thereof are butted to the bottom face and the standing up side face of the step portion to position two axes of the row bar among XYZ directions, successively, positioning of the row bar in one remaining direction along longitudinal direction of the row bar mounted on the step portion is performed by moving the table in the one remaining axial direction.

Abstract: An electrical lapping guide for a magnetic tape head is provided with a resistive transverse stripe with a longitudinal height affixed to a substrate. A pair of leads extend from the stripe with a notch formed therebetween. The notch has a height corresponding to a lapping target limit for associated tape head elements. During material removal of the transverse stripe and the tape head elements, resistance is measured across the stripe and a dramatic increase in resistance indicates that the material removal has reached the notch. A method for accurately machining a magnetic tape head is provided by depositing tape head elements and a resistive stripe with a notch on a substrate. Resistance is measured across leads on either side of the notch for discontinuing machining of the stripe due to a dramatic increase in resistance.

Abstract: It is an object of the present invention to provide a method for investigating magnetic domains, the method capable of easily grasping behavior of the magnetic domains in a head manufacturing process, and further to provide a testing method of a magnetic head capable of evaluating whether the writing performance of the magnetic head is good or not. The method for investigating magnetic domains comprises supplying direct current (DC) to a coil of an electromagnetic transducer provided in a magnetic head for writing data onto a magnetic recording medium; measuring an inductance of the electromagnetic transducer at each current value while varying the current value of the direct current; and investigating behavior of magnetic domains in a magnetic core of the electromagnetic transducer based on a relationship between the current values and the inductances.

Abstract: A method comprises an opposing step of arranging a light-shielding film 50 having a recessed surface 52 and a pinhole 54 formed within the recessed surface 52 such that an end face 54X of the pinhole 54 of the light-shielding film 50 on the recessed surface 52 side and a light exit surface 4B oppose each other, while the shortest distance A52 between the light-shielding film 50 and a medium-opposing surface S in a thickness direction of the light-shielding film 50 is shorter than the shortest distance A54 between the end face 54X of the pinhole 54 on the side opposite from a transparent substrate 58 and the light exit surface 4B; a light-emitting step of causing a light-emitting device 3 to emit emission light 3A; and a detecting step of detecting the light transmitted through the pinhole 54 after being emitted from the light exit surface 4B.

Abstract: A system and method for the production level screening of low flying magnetic heads in the manufacture of disk drive head disk assemblies (HDAs) is disclosed. A test disk is provided and has a plurality of bumps extending from at least one surface thereof to a predetermined height between 2 and 12 nanometers. The test disk is rotated to fly a head of a head gimbal assembly selected from the group adjacent the surface of the test disk. An interaction of the head with one or more of the plurality of bumps may be sensed and the head gimbal assembly may be screened out from the group in response to the sensing of the interaction.

Abstract: A method for detecting head-disc contact is disclosed. The method comprises locating a head including a head positioning microactuator and at least one of a read transducer and a write transducer adjacent to a disc such that the head is in communication with the disc, monitoring an output signal from the head positioning microactuator of the head, and evaluating the output signal to determine if the head contacts the disc.

Abstract: A thin film magnetic head integrated structure is provided. A plurality of thin film magnetic head bars include a plurality of thin film magnetic head precursors, a plurality of RLG sensors for read head core, and a plurality of RLG sensors for write head core, the read head core including a magnetoresistive element that performs a read process and the write head core including a magnetic pole layer that performs a write process.

Abstract: Write heads and corresponding methods of fabrication are provided using multiple electronic lapping guides to collect information regarding multiple distances of a write head, such as a throat height and a flare point distance of a write pole. A method of fabricating a write head includes fabricating a write pole and a corresponding write pole ELG. The method further includes fabricating a trailing shield and a corresponding trailing shield ELG. The method further includes performing a lapping process on the write head, and monitoring a lapping depth of the lapping process based on the resistance of the write pole ELG and the resistance of the trailing shield ELG.

Abstract: A correcting method for reducing variations in floating height and gram load of a floating-type magnetic head device is disclosed. The correcting method includes a first correcting step of detecting a roll-angle corresponding amount in the free state of the front end of the front end and bending the load beam in the direction where the roll-angle corresponding amount approaches zero, and a second correcting step of putting the floating-type magnetic head device into a temporarily mounted state with respect to the load beam, detecting a roll-angle corresponding amount at the tongue piece of the flexure in the temporarily mounted state, and bending at least one of the left and right outriggers in the direction where the roll-angle corresponding amount approaches zero.

Abstract: A method of measuring temperature of a TMR element includes a step of obtaining in advance a temperature coefficient of element resistance of a discrete TMR element that is not mounted on an apparatus, by measuring temperature versus element resistance value characteristic of the discrete TMR element in a state that a breakdown voltage is intentionally applied to the discrete TMR element and a tunnel barrier layer of the discrete TMR element is brought into a stable conductive state, a step of bringing a tunnel barrier layer of a TMR element actually mounted on the apparatus into a stable conductive state by intentionally applying the breakdown voltage to the mounted TMR element having the same structure as that of the discrete TMR element whose temperature coefficient has been measured, a step of measuring an element resistance value of the mounted TMR element with the tunnel barrier layer that has been brought into a stable conductive state, and a step of obtaining a temperature corresponding to the measure

Abstract: A method of lapping a magnetic head slider includes a step of lapping a lapping surface of a row bar provided with a plurality of MR read head elements arranged along at least one line, a step of obtaining at least one output signal from at least one of the plurality of MR read head elements of the row bar during lapping, the at least one output signal corresponding to element resistance, a step of detecting at least one peak value of the obtained at least one output signal, and a step of controlling an amount of lapping of the row bar depending upon the detected at least one peak value.

Abstract: The lapping of a slider is controlled based on an amplitude of a readback signal which is produced from an externally applied magnetic field. A lapping plate is used to lap a slider which includes at least one magnetic head having a read sensor. During the lapping, a coil produces a magnetic field around the slider and processing circuitry monitors both a readback signal amplitude and a resistance of the read sensor. The lapping of the slider is terminated based on the monitoring both the readback signal amplitude and the resistance. Preferably, the lapping of the slider is terminated when the resistance is within a predetermined resistance range and the readback signal amplitude is above a predetermined minimum amplitude threshold or reaches its peak value. Asymmetry can also be measured in the described system, where the lapping process is terminated based on asymmetry as well as resistance and amplitude measurements.

Abstract: A new fixture which is capable of holding an HAS throughout all processes so that Quasi-Static Test can be done before swaging. Also, a process for testing the HAS by means of the fixture. An embodiment method may include loading head gimbal assemblies and an actuator using an automatic loading machine; in-line dressing of the head gimbal assemblies; ultrasonic bonding of the head gimbal assemblies; testing said head gimbal assemblies in-line while quasi-static; and if an head gimbal assemblies fails to pass the testing, rejecting and reworking in-line; in-line coating of the head gimbal assemblies; ultra-violet curing of the head gimbal assemblies; in-line swaging said head gimbal assemblies and actuator to form an head stack assemblies; and visual checking and unloading of said head stack assemblies.

Abstract: A device and method for testing a slider of a head-gimbal assembly during disc drive manufacturing. The device includes a test disc, an actuator arm and a control module. The test disc has a first circumferential area for detecting contact between the slider and the test disc and a second circumferential area for burnishing sliders that contact the first circumferential area as the test disc rotates at or above the predetermined velocity. The head-gimbal assembly is affixed to the actuator arm such that the slider is operable to move between an inner diameter and an outer diameter of the test disc. The control module controls the movement of the actuator arm, and thus the slider, relative to the test disc. The control module monitors the slider-disc interface for contact therebetween. If contact is detected, the slider is either burnished or the head-gimbal assembly is discarded altogether.

Abstract: According to one embodiment, a method for manufacturing a thin film magnetic head includes forming on a substrate magnetic head portions having a magnetoresistive element and resistance detection elements for measuring an amount of polishing; slicing the substrate to form at least one row bar; polishing the ABS of each row bar; forming rails on the polished ABS; and cutting each row bar to separate each magnetic head portion. The step of polishing the ABS includes measuring a resistance of each resistance detection element and a resistance of each magnetoresistive element; calculating an offset value between the resistance detection element and the magnetoresistive element; and calculating a final resistance of the resistance detection element by using the calculated offset value. When the resistance of the resistance detection element reaches the final resistance, polishing of the ABS of the row bar is terminated. Other methods are presented as well.

Abstract: Embodiments of the present invention provide a method of manufacturing a magnetic head slider, the method being adapted so that throat height of a main magnetic pole piece of a perpendicular recording magnetic head can be controlled with high accuracy. According to one embodiment, a first Electrical Lapping Guide element (ELG) is disposed on the same layer as a plated underlayer of a shield of one write head in a row bar, and other ELGs are disposed on the same layer as that of a main magnetic pole piece of another write head. Front end positions (Tops) are detected from changes in resistance values of the other ELGs and an ending position of lapping is calculated. Since the front end positions (Tops) of the other ELGs are accurate, it is possible to assign a correlation to throat height “Th” of the main magnetic pole piece and the resistance value of the first ELG by detecting this resistance value existing when the front end positions (Tops) are detected.

Abstract: Provided is an apparatus for adjusting static attitude of a thin film magnetic head attached to a flexure of a head arm assembly. The apparatus has an adjusting unit for bending the flexure, a laser emitter unit for irradiating a laser beam to a bent area of the flexure a measuring unit for measuring a static attitude angle of the thin film magnetic head, and a computer system including a CPU and a memory unit in which adjustment conditions corresponding to static attitude angles of the thin film magnetic head are previously ranked and memorized. The CPU is configured to retrieve from the memory unit a particular adjustment condition corresponding to a measured angle supplied from the measuring unit and supply the retrieved adjustment condition to the adjusting unit, enabling the adjusting unit to bend the flexure based on the retrieved adjustment condition supplied from the computer system.

Abstract: An apparatus for lapping a slider comprises a lapping head for supporting elements while pressing the elements against a rotating lapping plate, the elements that are to be formed into sliders, a holding mechanism for supporting the lapping head, the holding mechanism having a first engaging member that extends in a vertical direction, a base for supporting the holding mechanism, the base having a second engaging member that extends in the vertical direction, wherein the second engaging member is engaged with the first engaging member to form an internal space therebetween, and a decompressing mechanism for decompressing the internal space. The holding mechanism is subjected to vertically upward force from the decompressed internal space in order to be movably supported by the base in the vertical direction.

Abstract: It is an object of the present invention to provide a method for investigating magnetic domains, the method capable of easily grasping behavior of the magnetic domains in a head manufacturing process, and further to provide a testing method of a magnetic head capable of evaluating whether the writing performance of the magnetic head is good or not. The method for investigating magnetic domains comprises supplying direct current (DC) to a coil of an electromagnetic transducer provided in a magnetic head for writing data onto a magnetic recording medium; measuring an inductance of the electromagnetic transducer at each current value while varying the current value of the direct current; and investigating behavior of magnetic domains in a magnetic core of the electromagnetic transducer based on a relationship between the current values and the inductances.

Abstract: The method for testing a characteristic of a magnetic head is performed in the form of a wafer, especially in a heating state and a cooling state. The method for testing a characteristic of a magnetic head, in which a wafer including a dummy read-element having a size equal to that of a completed read-element, a product read-element and a heat conductive section being provided in the vicinity of the dummy read-element is tested as a test sample, comprises the steps of: applying an external magnetic field to the test sample; bringing a heat conducting member into contact with the heat conductive section so as to heat or cool the dummy read-element via the heat conductive section; and testing an electromagnetic conversion characteristic of the dummy read-element in a heating state or a cooling state.

Abstract: The method of producing a head slider is capable of restraining variation of processing read-elements, forming the read-elements having a prescribed size, improving production yield and improving magnetoresistance characteristics. The method comprises the steps of: forming grooves in a wafer substrate, wherein the grooves correspond to raw bars to be cut from the wafer substrate; filling the grooves with an insulating material; forming read-elements and write-elements on the surface of the wafer substrate, whose grooves have been filled with the insulating material; and cutting the wafer substrate, on which the read-elements and the write-elements have been formed, along the grooves so as to form the raw bars, whose base members are constituted by the wafer substrate and coated with the insulating material.

Abstract: The method of producing a thin film magnetic head from a raw bar, in which a plurality of combinations of a thin film magnetic head including a reproducing head and an ELG element are continuously formed, comprises the steps of: measuring resistance of a magnetoresistance effect element section of each ELG element as first resistance; measuring resistance of a magnetoresistance effect element section of each thin film magnetic head as second resistance; detecting existence or nonexistence of a smear in an air bearing surface of each thin film magnetic head on the basis of the difference between the first resistance and the second resistance; and removing the smear from only the thin film magnetic head in which the existence of the smear is detected.