Design And Preparation Of Spin-Valve GMR Maerials And Devices

In this paper, a GMR (giant magnetoresistance) thin-film material based sensor technology, the paper first GMR film structure design optimization, based on the study of the preparation process of the GMR film, by optimizing the process parametersobtained a film material having excellent magnetoresistive characteristics, improve the giant magnetoresistance effect; design analysis of the structure of the sensor unit based on the GMR film and the preparation to improve the sensitivity of the sensor unit; analysis of the principle of the structure of the magnetic encoder and the fielddistribution, design the structure of the encoder and associated circuitry design basis of research in spintronics as well as the theory of the giant magnetoresistance effect, the basic functions of the GMR sensor.Papers in the Si/SiO on the substrate, prepared by high-performance giant magnetoresistance spin valve nano-film material, the structure of the Si/SiO/Ta (4.0of5nm)/NOLs/NiFe (1.0nm)/CoFe (3.0nm)/Cu/CoFe (2.5nm)/NOL/CoFe (2.5nm)/IrMn (10.0nm)/Ta (4.0nm), the performance of the material as follows:a magneto-resistance ratio of10.5%, the material sensitivity1.2%/OE, temperature stability (between-100℃-+100℃magnetoresistance ratio decreased by9.5%), and meet the requirements of the project. On this basis, by means of lithography, etching and other processes, to produce the GMR spin valve device, its performance as follows:the device sensitivity0.61mV/(V·Oe), the magnetic field resolution (room temperature) of1.2x10-4Oe detect the magnetic field range (-10Oe-+10Oe), Operating temperature-60℃-+80℃to meet the project requirements. Finally, the development of a magnetic rotary encoder head prototype based on the GMR spin valve element. The experimental results show that, the paper giant magnetoresistive sensor structure is feasible, the expected results match the experimental results and the design.