Ji-Goo Ryu

Magnetoelectric Characteristics on Layered Ni-PZT-Ni, Co, Fe Composites for Magnetic Field Sensor

Abstract: The magnetoelectric characteristics on layered Ni-PZT-Ni , Co, Fe composites by epoxy bonding for magnetic field sensor were investigated in the low-frequency range. The ME coefficient of Ni-PZT-Ni, Ni-PZT-Co and Ni-PZT-Fe composites reaches a maximum of 200 mV / cm·Oe at H dc =110 Oe , 106 mV/cm·Oe at H dc =90 Oe and 87 mV/cm·Oe at H dc =160 Oe , respectively. A trend of ME charateristics on Ni-PZT-Co , Ni-PZT-Fe composites was similar to that of Ni-PZT-Ni composites . The ME output voltage shows linearly proportional to ac field H ac and is about 0∼150 mV at H ac =0∼7 Oe and f =110 Hz in the typical Ni-PZT-Ni sample. The frequency shift effect due to the load resistance R L shows that the frequency range for magnetic field sensor application can be modulated with appropriate load resistance R L . This sample will allow for a low-magnetic ac field sensor in the low-frequency (near f =110 Hz ). Keywords: Magnetic field sensor, Magnetoelectric effect, Laminate structure, Magnetostriction coefficient

Magnetoelectric Characteristics on Layered Fe 78 B 13 Si 9 /PZT/Fe 78 B 13 Si 9 Composites for Magnetic Field Sensor

Abstract The magnetoelectric characteristics on layered Fe 78 B 13 Si 9 /PZT and Fe 78 B 13 Si 9 /PZT/Fe 78 B 13 Si 9 (t m =0.017, 0.034 mm) composites byepoxy bonding for magnetic field sensor were investigated in the low-frequency range and resonance frequency range. The optimal biasmagnetic field dc of these samples was about 23~63 Oe range. The Me coefficient of H Fe 78 B 13 Si 9 /PZT/Fe 78 B 13 Si 9 (t m =0.034 mm) com-posites reaches a maximum of 186 mV/cm·Oe at H dc =63 Oe, =50 Hz and a maximum of 1280 mV/cm·Oef at H dc =63 Oe, resonancefrequency f r =95.5 KHz. The output voltage shows linearity proportional to ac fields H ac and is about =0~130.6 mV at U H ac =0~7 Oe,f=50 Hz, U=0~12.4 V at H ac =0~10 Oe, f r =95.5 KHz(resonance frequency). The optimal frequency(=50 Hz) of this sample is aroundfthe utility ac frequency(f=60 Hz). Therefore, this sample will allow for ac magnetic field sensor at utility frequency and low bias mag-netic fields H dc .Keywords: Magnetic field sensor, Magnetoelectric effect, Magnetostriction coefficient, Electromechanical coefficient, Loadresistance

Electric Circuits Modeling of Magnetoelectric Bulk Composites in Low Frequency

Magnetoelectric(ME) bulk composites with PZT-PNN-PZN/ were prepared by using a conventional ceramic methods and investigated on the ME voltage vs frequency of ac magnetic fields. We made the electric equivalent circuits by using the Maxwell-Wagner model and simulated the frequency dependence of ME voltage in low frequency region. ME devices were described by a series of two equivalent circuits of piezoelectric and magnetic, which have the relaxation time due to the interaction between ME device and load resistor. Equivalent circuit of piezoelectric material is independent of frequency. However ferrite magnetic materials have Debye absorption and dipolar dispersion, whose equivalent circuit is a function of frequency. Therefore we suggest the resistance in the equivalent circuit is proportion to and the capacitance is in inverse proportion to in the magnetic materials.

Piezoelectric/magnetic Properties and Magnetoelectric Effects in (1-x) [0.5PZT-0.25PNN-0.25PZN] - x [Ni 0.9 Zn 0.1 Fe 2 O 4 ] Particulate Ceramic Composites

Magnetoelectric composites with compositions (1-x)[0.5PZT-0.25PNN-0.25PZN](ferroelectric) - x[](ferrite) in which x varies as 0, 0.1, 0.2, 0.4, 0.6, 0.8, 1.0 were prepared by conventional ceramic process. The presence of two phases (ferroelectric phase with large grain and ferrite phase with small grain) in the particulate ceramic composites was confirmed by XRD, SEM and EDX. The ferroelectric and magnetic properties of the composites were studied by measuring the P-E and M-H hysterisis loop on the composite composition (x

Characteristics of the 2-D SSIMT using a CMOS Process

A novel 2-Dimensional Suppressed Sidewall Injection Magnetotransistor (SSIMT) with high linearity has been fabricated on the standard CMOS technology and experimentally verified. The novel 2-Dimensional SSIMT overcomes the restriction of the standard CMOS technology. Experimental results of the fabricated 2-Dimensional SSIMT show that the variation of each collector output currents are extremely linear as a function of magnetic field from -200mT to 200mT at

Fabrication and characteristics of the suppressed sidewall injection magnetotransistor using a CMOS process

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Characteristics of the Suppressed Sidewall Injection Magnetotransistor using a CMOS Process

We report the implementation of a novel suppressed sidewall injection magnetotransistor. The novel device overcomes the restriction of the standard CMOS technology and achieves high linearity. The fabricated device is designed, based on the Hynix 0.6 /spl mu/m standard CMOS technology and is experimentally verified. Experimental results show that the change of the collector current is extremely linear as a function of the magnetic induction at I/sub B/=500 /spl mu/A, V/sub CE/=2 V and V/sub SE/=5 V. The relative sensitivity is up to 120%/T. The nonlinearity of the fabricated device is measured about 1.4%.

A Fast Locking Phase Locked Loop with Multiple Charge Pumps

We report the implementation of a novel suppressed sidewall injection magnetotransistor. The novel device overcomes the restriction of the standard CMOS technology and achieves high linearity. The fabricated device is designed, based on the Hynix 0.6 /spl mu/m standard CMOS technology and is experimentally verified. Experimental results show that the change of the collector current is extremely linear as a function of the magnetic induction at I/sub B/=500 /spl mu/A, V/sub CE/=2 V and V/sub SE/=5 V. The relative sensitivity is up to 120%/T. The nonlinearity of the fabricated device is measured about 1.4%.