Title :
Characteristics of NiFe/CuNi multilayer GMR sensors for vertical GMR heads
Author :
Mizuguchi, Tetsuya ; Terada, Shouji ; Miyauchi, Teiichi ; Matsuzono, Atsushi
Author_Institution :
Res. Center, Sony Corp., Yokohama, Japan
fDate :
7/1/1998 12:00:00 AM
Abstract :
By using a novel NiFeCr buffer layer, a substantial improvement in a GMR ratio of 4.5% with a low saturation field of 19 Oe was obtained. The structure of all GMR multilayers was glass/NiFeCr[5 nm]/NiFe[1.7 nm]/(CuNi[2.3 nm]/NiFe[1.7 nm])3/Cr[2 nm]. The change in sheet resistance was 0.8 Ohms/square. Magnetoresistances, current density effects and transfer curves for 2, 1, and 0.5 micron trackwidth GMR sensors of these structures are described. At a trackwidth of 0.5 μm, maximum field sensitivity of 215 μm V/Oe was obtained with a sensor length of 2 μm, a sense current of 3 mA. No degradation in magnetoresistance of sheet CMR was found after annealing at 270°C. However, sensor-size dependent thermal degradation was observed
Keywords :
chromium; chromium alloys; copper alloys; current density; giant magnetoresistance; iron alloys; magnetic heads; magnetic multilayers; magnetic recording; magnetic sensors; magnetoresistive devices; nickel alloys; 0.5 to 2 mum; 1.7 to 5 nm; 270 C; 3 mA; GMR ratio; GMR sensors; NiFe/CuNi multilayer GMR sensors; NiFeCr buffer layer; NiFeCr-NiFe-CuNi-NiFe-Cr; current density effects; glass/NiFeCr/NiFe/CuNi/NiFe/Cr; low saturation field; maximum field sensitivity; sense current; sensor length; sensor-size dependent thermal degradation; sheet resistance; trackwidth; transfer curves; vertical GMR heads; Buffer layers; Colossal magnetoresistance; Current density; Giant magnetoresistance; Glass; Magnetic multilayers; Magnetic sensors; Nonhomogeneous media; Sensor phenomena and characterization; Thermal degradation;
Journal_Title :
Magnetics, IEEE Transactions on
