Giant Magneto-Impedance Effect Sensor In Micro-Patterned Co-Based Amorphous Ribbon And Its Study Of Circuit System

The application of magnetic sensor has a long history,from ancient times of navigational compass to contemporary and now is widely used in aerospace,automation measurement,magnetic storage,such as the biomedical industry,which plays an important role.In recent years,a new kind of magnetic sensor technology the Giant magneto-impedance(Giant Magneto impedance,GMI)effect has rapidly developed.Since in 1992,reported in CoFeNi amorphous wires has drawn great attention to the researchers around the world,compared with other traditional magnetic sensor,there are three major advantages: Firstly,relatively simple manufacturing process,thus greatly reduce the production cost.Secondly,not only easy to realize miniaturization and integration,and can achieve high sensitivity,low power consumption and low hysteresis information and other technical requirements.Thirdly,it can be achieved in a wide temperature range under rapid sensitive detection of weak magnetic field.This article chose co-based amorphous ribbon,systematically studied the meander shape structure ribbon,giant magneto-impedance effect and the relationship between the parameters of the samples,and according to the preparation of the sensor structures,peripheral circuit.The main results were as follows:1.In this paper,micro-patterned Co-based amorphous ribbon with different st ructures are fabricated by MEMS technology,including bonding,lithography and electroplating.The commercial amorphous ribbons(VITROVAC 6025)were pur chased from VACUUMSHMELZE? company.The structure of micro-patterned ri bbons are designed for meander shape with different turns(turns 1-3).The effec t of external magnetic orientation on GMI ratios were studied in the frequency range of 1-40 MHz.It is found that GMI ratios all presented negative value,wh ich is related to the material property,namely magnetic anisotropy.2.Compared with the GMI ratios obtained at transverse external magnetic field,the GMI ratios obtained at longitudinal external magnetic field is higher.The value of-69.93% was obtained at a current frequency of 10 MHz and the magnetic field of 150 Oe.With the increase of the number of turns,the maximum of the GMI ratio increases from 31.2 % for the one turn sample to the 69.93% for the sample with three turns.The GMI ratio have the same change trend,with increasing magnetic field decreases,reaches a negative maximum at a saturation magnetic field.3.This article proposes and studies a new type of GMI sensor detection system,the system is composed by the signal generator,V/I conversion circuit and the true value of converter.In 1 MHZ to 5 MHZ excitation signal frequency range,the GMI sensor useing new type test system were measured,the measure of results and the HP 4194 A impedance analyzer in the same conditions has carried on the comparative analysis,when the frequency is 5 MHZ,comparison results show that the system error range is less than 1.5%.Within the scope the 5 ~ 15 Oe,the sensor output curve linearity is good,the sensor sensitivity is 93.67 mv/Oe,output linearity is 16.67%.