Authors: Liang Sheng Qiang, Dong Yan Tang, Mu Han
Abstract: In present work, sol-gel process is used to direct the organization of high quality and pore-free
parasite PZT thin films with a composition near the morphotropic phase boundary (Zr/Ti = 52/48). The
PZT transparent sol can be obtained by dissolving the zirconium oxynitrate, butyl titanate and lead acetate
in ethylene glycol with the molar ratio of 0.52:0.48:1 and the PZT gel can be gained by spin-coating. In
such process, PZT thin films can be readily prepared by hydrolysis on hot plate at 350°C for 20min and
annealing in RTA at 650°C for 1 minute. The structural and electric characteristics of the films have been
carried out by XRD, AFM and the C-V measurements, etc. Experimental results have indicated that by
treating film RTA at 6508 for 1 minute film with perfect crystallization and good surface morphology
with a RMS roughness of 2.0nm can be obtained, and the remnant polarization Pr (28.5 μC/cm2) and
coercive field Ec (39.8kV/cm) are obtained in the P-E hysteresis loops. The films have a dielectric
constant ε of 1080 and a dielectric loss tanδ of 0.01 at 1 kHz. Ferroelectric polarization fatigue test of the
films has shown that high fatigue resistance up to 3 × 1010 cycles before Pr is decreased by 50%.
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Authors: E.N. Sheftel, Rauf S. Iskhakov, S.V. Komogortsev, P.K. Sidorenko, Nikolai S. Perov
Abstract: Data on the random magnetic anisotropy and exchange correlation length in soft magnetic nanocrystalline Fe79Zr10N11 films were obtained using a calculation technique in frame of the random magnetic anisotropy model. The calculations are performed using approach magnetization to saturation curves. The local magnetic anisotropy fields (Ha), and magnetic anisotropy correlation radii (Rс) reduced to =(A/K)1/2 were determined for the films annealed at 475 and 6000 C for 0.5, 1, 2, and 3 h. The correlation Hc ~(Rc/)3 for the all annealed films was found.
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Authors: Ramli, Euis Sustini, Nurlaela Rauf, Mitra Djamal
Abstract: The giant magnetoresistance (GMR) effect in FeMn/NiCoFe/Cu/NiCoFe spin valve prepared by dc opposed target magnetron sputtering is reported. The spin valve thin films are characterized by Scanning Electron Microscopy (SEM), Vibrating Sample Magnetometer (VSM) and magnetoresistance ratio measurements. All measurements are performed in room temperature. The inserted 45 mm thickness FeMn layer to the NiCoFe/Cu/NiCoFe system can increase the GMR ratio up to 32.5%. The coercive field to be increased is compared with different FeMn layer thickness. Furthermore, the coercive field (Hc) decreases with increasing FeMn layer thickness. Magnitude of coercive field is 0.1 T, 0.09 T and 0.08 T for FeMn layer thickness is 30 nm, 45 nm and 60 nm, respectively. The FeMn layer is used to lock the magnetization in the ferromagnetic layer through the exchange anisotropy. This paper will describe the development of a GMR spin valve and its magnetic properties.
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Authors: Rachasak Sakdanuphab, Aparporn Sakulkalavek
Abstract: In this work, we study the resistive switching behavior of a new model metal/insulator/metal (MIM) junction. The MIM junction consists of titanium front electrode, zinc oxide insulation layer and molybdenum back electrode. The Ti/ZnO/Mo structure was prepared on 3x3 cm2 soda lime glass substrates using dc magnetron sputtering for metal electrodes and rf magnetron sputtering for ZnO layer. The thicknesses of Ti, ZnO and Mo films were controlled at 200nm, 50nm and 500nm, respectively. The crystalline structure and microstructure of the films were characterized by X-ray diffraction (XRD) and atomic force microscopy (AFM). The current-voltage (I-V) characteristics of the device cells were obtained by using dc voltage sweep mode. The XRD spectra of the devices show Mo(100) and ZnO(002) preferred orientations. The Mo and ZnO film surfaces exhibit dense crystallized grains with the root mean square roughness (RMS) of 1.0 and 1.4 nm, respectively. The device cells behave unipolar resistive switching characteristics with reversible, controllable and reliability within 150 cycles. The difference between high resistive state (HRS) and low resistive state (LRS) is about 103 times. A low operating voltage range of 0.50-0.60V is obtained for switching from HRS to LRS at a current compliance of 10mA. The new MIM structure was demonstrated and suggested a potential to use as nonvolatile memory application.
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