Abstract: Magnetic recording heads and associated methods of fabrication are disclosed. A magnetic recording head has a first shield and a magnetoresistance (MR) read element formed on the first shield. The first shield has a shield height that is defined by a distance between the air bearing surface (ABS) of the recording head and a back edge of the first shield that is opposite the ABS. The MR read element has a stripe height that is defined by a distance between the air bearing surface (ABS) of the recording head and a back edge of the MR read element that is opposite the ABS. The magnetic recording heads as disclosed herein have a stripe height that is greater than the shield height.

Abstract: Test methods and components are disclosed for testing resistances of magnetoresistance (MR) sensors in read elements. Test components are fabricated on a wafer with a first test lead, a pseudo sensor, and a second test lead. The test leads and MR sensor are fabricated with similar processes as first shields, MR sensors, and second shields of read elements on the wafer. However, the pseudo sensor in the test component is fabricated with lead material (or another material having similar resistance properties) instead of an MR thin-film structure like an MR sensor. Forming the pseudo sensor from lead material causes the resistance of the pseudo sensor to be insignificant compared to the lead resistance. Thus, a resistance measurement of the test component represents the lead resistance of a read element. An accurate resistance measurement of an MR sensor in a read element may then be determined by subtracting the lead resistance.

Abstract: Test methods and components are disclosed for testing the quality of a fabrication process used to form read elements in magnetic heads. A wafer is populated with one or more test components along with magnetic heads. The test components are formed by the same or similar fabrication processes as the read elements, but do not include a conductive MR sensor between the test leads. By measuring the resistance of the test components, the formation of parasitic shunts can be identified in the test components, which may indicate the formation of parasitic shunts in the read elements. Thus, the quality of the fabrication process in forming read elements in magnetic head may be determined.

Abstract: Methods of fabricating magnetic read heads are provided which reduce the width of the scratch exposure region of a read head. During normal fabrication processes, a read head is formed with a first shield, a read element formed on the first shield, and hard bias layers formed on either side of the read element. The width of the read elements and the hard bias layers define an initial scratch exposure region. According to embodiments herein, a mask structure is formed to protect the read element and first portions of the hard bias layers proximate to the read element. A removal process is then performed to remove second portions of the hard bias layers that are not protected by the mask structure, which defines a final scratch exposure region that is smaller than the initial scratch exposure region.

Abstract: A combined manufacturable wafer and test device for measuring a tunneling-magnetoresistance property of a tunneling-magnetoresistance, sensor-layer structure. The combined manufacturable wafer and test device comprises a tunneling-magnetoresistance, sensor-layer structure disposed on a substrate. The combined manufacturable wafer and test device also comprises a plurality of partially fabricated tunneling-magnetoresistance sensors; at least one of the partially fabricated tunneling-magnetoresistance sensors is disposed at one of a plurality of first locations. The test device is disposed on the substrate at a second location different from the plurality of first locations. The test device allows measurement of the tunneling-magnetoresistance property of the tunneling-magnetoresistance, sensor-layer structure using a current-in-plane-tunneling technique.

Abstract: Test methods and components are disclosed for testing resistances of magnetoresistance (MR) sensors in read elements. Test components are fabricated on a wafer with a first test lead, a test MR sensor, and a second test lead. The test leads and test MR sensor are fabricated with similar processes as first shields, MR sensors, and second shields of read elements on tie wafer. However, the test MR sensor is fabricated with an area that is larger than areas of the MR sensors in the read elements. The larger area of the test MR sensor causes the resistance of the test MR sensor to be insignificant compared to the lead resistance. Thus, a resistance measurement of the test component represents the lead resistance of a read element. An accurate resistance measurement of an MR sensor in a read element may then be determined by subtracting the lead resistance.

Abstract: A test-device system and method for deconvoluting measurements of effects of a sensor-width definition process from measurements of effects of a sensor-stripe-height-definition process in a manufacture of a magnetic sensor. The test-device system comprises a first test device for generating data to characterize a sensor-width-definition process. The test-device system also comprises a second test device for generating data to characterize a sensor-stripe-height-definition process. The test-device system allows independent characterization of a sensor-width parameter and a sensor-stripe-height parameter.

Abstract: Test methods and components are disclosed for testing the quality of the ground connection fabrication process for ESD shunt resistors in magnetic heads. A wafer is populated with one or more test components along with magnetic heads. The test components are fabricated with ESD shunt resistor ground connections created by the same or similar process used to fabricate the ESD shunt resistor ground connections in magnetic heads on the wafer. The resistance of the test component ground connections may then be measured in order to determine the quality of the ground connections formed by the fabrication process. The quality of the ground connection fabrication process may then be determined based on the measured resistance of the test components.

Abstract: Tunneling magnetoresistive (TMR) electrical lapping guides (ELG) are disclosed for use in wafer fabrication of magnetic sensing devices, such as magnetic recording heads using TMR read elements. A TMR ELG includes a TMR stack comprising a first conductive layer, a barrier layer, and a second conductive layer of TMR material. The TMR ELG also includes a first lead and a second lead that connect to conductive pads used for applying a sense current to the TMR ELG in a current in plane (CIP) fashion. The first lead contacts one side of the TMR stack so that the first lead contacts both the first conductive layer and the second conductive layer of the TMR stack. The second lead contacts the other side of the TMR stack so that the second lead contacts both the first conductive layer and the second conductive layer of the TMR stack.

Abstract: Test methods and components are disclosed for testing the quality of a fabrication process used to form read elements in magnetic heads. A wafer is populated with one or more test components along with magnetic heads. The test components are formed by the same or similar fabrication processes as the read elements, but do not include a conductive MR sensor between the test leads. By measuring the resistance of the test components, the formation of parasitic shunts can be identified in the test components, which may indicate the formation of parasitic shunts in the read elements. Thus, the quality of the fabrication process in forming read elements in magnetic head may be determined.

Abstract: A combined manufacturable wafer and test device for measuring a tunneling-magnetoresistance property of a tunneling-magnetoresistance, sensor-layer structure. The combined manufacturable wafer and test device comprises a tunneling-magnetoresistance, sensor-layer structure disposed on a substrate. The combined manufacturable wafer and test device also comprises a plurality of partially fabricated tunneling-magnetoresistance sensors; at least one of the partially fabricated tunneling-magnetoresistance sensors is disposed at one of a plurality of first locations. The test device is disposed on the substrate at a second location different from the plurality of first locations. The test device allows measurement of the tunneling-magnetoresistance property of the tunneling-magnetoresistance, sensor-layer structure using a current-in-plane-tunneling technique.

Abstract: Test methods and components are disclosed for testing the quality of the ground connection fabrication process for ESD shunt resistors in magnetic heads. A wafer is populated with one or more test components along with magnetic heads. The test components are fabricated with ESD shunt resistor ground connections created by the same or similar process used to fabricate the ESD shunt resistor ground connections in magnetic heads on the wafer. The resistance of the test component ground connections may then be measured in order to determine the quality of the ground connections formed by the fabrication process. The quality of the ground connection fabrication process may then be determined based on the measured resistance of the test components.

Abstract: A disk drive head slider for a magnetic disk drive is provided. The head slider includes a tunnel magnetic resistance device for reading data on a magnetic disk and a dedicated noncorrosive smear detector for measuring resistance wherein the resistance corresponds to a level of smear associated with the head slider.

Abstract: Test methods and components are disclosed for testing resistances of magnetoresistance (MR) sensors in read elements. Test components are fabricated on a wafer with a first test lead, a pseudo sensor, and a second test lead. The test leads and MR sensor are fabricated with similar processes as first shields, MR sensors, and second shields of read elements on the wafer. However, the pseudo sensor in the test component is fabricated with lead material (or another material having similar resistance properties) instead of an MR thin-film structure like an MR sensor. Forming the pseudo sensor from lead material causes the resistance of the pseudo sensor to be insignificant compared to the lead resistance. Thus, a resistance measurement of the test component represents the lead resistance of a read element. An accurate resistance measurement of an MR sensor in a read element may then be determined by subtracting the lead resistance.

Abstract: A wafer comprises a kerf region and a test chip. The kerf is a region in a wafer designated to be destroyed by chip dicing. The test chip is located within the kerf region and is configured to provide parametric data for a wafer fabrication process of a head. The test chip comprises a shield portion of a first shield layer electrically coupled to an element, a first pad within a second shield layer electrically coupled to the element, and a second pad within the second shield layer electrically coupled to the shield portion.

Abstract: A test-device system and method for deconvoluting measurements of effects of a sensor-width definition process from measurements of effects of a sensor-stripe-height-definition process in a manufacture of a magnetic sensor. The test-device system comprises a first test device for generating data to characterize a sensor-width-definition process. The test-device system also comprises a second test device for generating data to characterize a sensor-stripe-height-definition process. The test-device system allows independent characterization of a sensor-width parameter and a sensor-stripe-height parameter.

Abstract: Test methods and components are disclosed for testing resistances of magnetoresistance (MR) sensors in read elements. Test components are fabricated on a wafer with a first test lead, a test MR sensor, and a second test lead. The test leads and test MR sensor are fabricated with similar processes as first shields, MR sensors, and second shields of read elements on tie wafer. However, the test MR sensor is fabricated with an area that is larger than areas of the MR sensors in the read elements. The larger area of the test MR sensor causes the resistance of the test MR sensor to be insignificant compared to the lead resistance. Thus, a resistance measurement of the test component represents the lead resistance of a read element. An accurate resistance measurement of an MR sensor in a read element may then be determined by subtracting the lead resistance.

Abstract: Methods of fabricating magnetic read heads are provided which reduce the width of the scratch exposure region of a read head. During normal fabrication processes, a read head is formed with a first shield, a read element formed on the first shield, and hard bias layers formed on either side of the read element. The width of the read elements and the hard bias layers define an initial scratch exposure region. According to embodiments herein, a mask structure is formed to protect the read element and first portions of the hard bias layers proximate to the read element. A removal process is then performed to remove second portions of the hard bias layers that are not protected by the mask structure, which defines a final scratch exposure region that is smaller than the initial scratch exposure region.

Abstract: Magnetic recording heads and associated methods of fabrication are disclosed. A magnetic recording head has a first shield and a magnetoresistance (MR) read element formed on the first shield. The first shield has a shield height that is defined by a distance between the air bearing surface (ABS) of the recording head and a back edge of the first shield that is opposite the ABS. The MR read element has a stripe height that is defined by a distance between the air bearing surface (ABS) of the recording head and a back edge of the MR read element that is opposite the ABS. The magnetic recording heads as disclosed herein have a stripe height that is greater than the shield height.

Abstract: A disk drive head slider for a magnetic disk drive is provided. The head slider includes a tunnel magnetic resistance device for reading data on a magnetic disk and a dedicated sensor for measuring resistance wherein the resistance corresponds to a level of smear associated with the head slider.