Title :
Thin-film magnetic sensor using high frequency magneto-impedance (HFMI) effect
Author :
Senda, Masakatsu ; Ishii, Osamu ; Koshimoto, Yasuhiro ; Toshima, Tomoyuki
Author_Institution :
NTT Interdisciplinary Res. Lab., Ibaraki, Japan
fDate :
11/1/1994 12:00:00 AM
Abstract :
This study reports on the performance of a thin-film magnetic sensor which uses the high frequency magneto-impedance (HFMI) effect. In order to obtain a high sensitivity and a large voltage change ratio (ΔVpp/Vpp(0): corresponds to the MR ratio), a strip pattern, a closed magnetic circuit, and a NiFe/SIO2 multilayer film structure are adopted for the magnetic films of the sensor. A ΔVpp/Vpp(0) of 60-70% is achieved by applying an external magnetic field of several Oe. Moreover there is no hysteresis or no Barkhausen noise in this sensor, which has a magnetic film width of 10 μm. In terms of linearity, the sensor exhibits modulation degree (m) of 12% and a total harmonic distortion (THD) of 0.8%
Keywords :
harmonic distortion; iron alloys; magnetic multilayers; magnetic sensors; magnetoresistance; nickel alloys; silicon compounds; 10 mum; NiFe-SiO2; NiFe/SIO2 multilayer film; closed magnetic circuit; high frequency magneto-impedance; high sensitivity; modulation degree; strip pattern; thin-film magnetic sensor; total harmonic distortion; voltage change ratio; Frequency; Magnetic circuits; Magnetic films; Magnetic hysteresis; Magnetic multilayers; Magnetic sensors; Strips; Thin film circuits; Thin film sensors; Voltage;
Journal_Title :
Magnetics, IEEE Transactions on
