We apply the hybrid Monte Carlo （HMC） micromagnetie method to FeCo soft magnetic polycrystalline films and test the new method by comparing with the result worked out by micromagnetics using Landau Lifshitz-Gilbert ...We apply the hybrid Monte Carlo （HMC） micromagnetie method to FeCo soft magnetic polycrystalline films and test the new method by comparing with the result worked out by micromagnetics using Landau Lifshitz-Gilbert equations, and the magnetic properties of FeCo films are understood better by carefully considering the effects of polycrystalline microstructures. The hysteresis loops of the FeCo film from low temperature up to 1100K are simulated by the new HMC micromagnetic method.展开更多
The leakage current behaviours of polycrystalline BiFeO3 thin films are investigated by using both conductive atomic force microscopy and current-voltage characteristic measurements. The local charge transport pathway...The leakage current behaviours of polycrystalline BiFeO3 thin films are investigated by using both conductive atomic force microscopy and current-voltage characteristic measurements. The local charge transport pathways are found to be located mainly at the grain boundaries of the films. The leakage current density can be tuned by changing the post-annealing temperature, the annealing time, the bias voltage and the light illumination, which can be used to improve the performances of the ferroelectric devices based on the BiFeOa films. A possible leakage mechanism is proposed to interpret the charge transports in the polycrystalline BiFeO3 films.展开更多
Selected area laser-crystallized polycrystalline silicon （p-Si） thin films were prepared by the third harmonics （355 nm wavelength） generated by a solid-state pulsed Nd：YAG laser. Surface morphologies of 400 nm t...Selected area laser-crystallized polycrystalline silicon （p-Si） thin films were prepared by the third harmonics （355 nm wavelength） generated by a solid-state pulsed Nd：YAG laser. Surface morphologies of 400 nm thick films after laser irradiation were analyzed. Raman spectra show that film crystallinity is improved with in- crease of laser energy. The optimum laser energy density is sensitive to the film thickness. The laser energy density for efficiently crystallizing amorphous silicon films is between 440-634 mJ/cm^2 for 300 nm thick films and between 777-993 mJ/cm^2 for 400 nm thick films. The optimized laser energy density is 634, 975 and 1571 mJ/cm^2 for 300, 400 and 500 nm thick films, respectively.展开更多
In this paper,we report the successful growth of 0.5BiFeO_(3)-0.5PbFe_(0.5)Nb_(0.5)O_(3)/SrTiO_(3)/Si(001)heterostructure using RFcathode sputtering in an oxygen atmosphere.The deposited films have been investigated b...In this paper,we report the successful growth of 0.5BiFeO_(3)-0.5PbFe_(0.5)Nb_(0.5)O_(3)/SrTiO_(3)/Si(001)heterostructure using RFcathode sputtering in an oxygen atmosphere.The deposited films have been investigated by X-ray diffractometry and spectroscopic ellip-sometry(SE).0.5BiFeO_(3)-0.5PbFe_(0.5)Nb_(0.5)O_(3)films on silicon substrates with a strontium titanate buffer layer are single-phase,polycrystalline with a texture in the 001 direction.The unit cell parameters calculated in the tetragonal approximation were c=4.005±0.001Å;a=3.995±0.001Å.The presence in the films of small unit cell deformation arising from different unit cells parameters of the film and substrate is observed.Dielectric properties and capacitance-voltage characteristics have been measured.The ellipsometric parameters have been obtained.展开更多
基金Supported by the National Natural Science Foundation of China under Grant Nos 51171086 and 51371101
文摘We apply the hybrid Monte Carlo （HMC） micromagnetie method to FeCo soft magnetic polycrystalline films and test the new method by comparing with the result worked out by micromagnetics using Landau Lifshitz-Gilbert equations, and the magnetic properties of FeCo films are understood better by carefully considering the effects of polycrystalline microstructures. The hysteresis loops of the FeCo film from low temperature up to 1100K are simulated by the new HMC micromagnetic method.
基金supported by the Chinese Academy of Sciencesthe State Key Project of Fundamental Research of Chinathe Natural Science Foundation of Ningbo,China
文摘The leakage current behaviours of polycrystalline BiFeO3 thin films are investigated by using both conductive atomic force microscopy and current-voltage characteristic measurements. The local charge transport pathways are found to be located mainly at the grain boundaries of the films. The leakage current density can be tuned by changing the post-annealing temperature, the annealing time, the bias voltage and the light illumination, which can be used to improve the performances of the ferroelectric devices based on the BiFeOa films. A possible leakage mechanism is proposed to interpret the charge transports in the polycrystalline BiFeO3 films.
基金Project supported by the National Natural Science Foundation of China(Nos.50802118,60906005)the Natural Science Foundation of Guangdong Province,China(No.9451027501002848)
文摘Selected area laser-crystallized polycrystalline silicon （p-Si） thin films were prepared by the third harmonics （355 nm wavelength） generated by a solid-state pulsed Nd：YAG laser. Surface morphologies of 400 nm thick films after laser irradiation were analyzed. Raman spectra show that film crystallinity is improved with in- crease of laser energy. The optimum laser energy density is sensitive to the film thickness. The laser energy density for efficiently crystallizing amorphous silicon films is between 440-634 mJ/cm^2 for 300 nm thick films and between 777-993 mJ/cm^2 for 400 nm thick films. The optimized laser energy density is 634, 975 and 1571 mJ/cm^2 for 300, 400 and 500 nm thick films, respectively.
基金The study was carried out with the financial support of the Ministry of Science and Higher Education of the Russian Federation(State task in the field of scientific activity,scientific project No.(0852-2020-0032)/(BAZ0110/20-3-07IF)).
文摘In this paper,we report the successful growth of 0.5BiFeO_(3)-0.5PbFe_(0.5)Nb_(0.5)O_(3)/SrTiO_(3)/Si(001)heterostructure using RFcathode sputtering in an oxygen atmosphere.The deposited films have been investigated by X-ray diffractometry and spectroscopic ellip-sometry(SE).0.5BiFeO_(3)-0.5PbFe_(0.5)Nb_(0.5)O_(3)films on silicon substrates with a strontium titanate buffer layer are single-phase,polycrystalline with a texture in the 001 direction.The unit cell parameters calculated in the tetragonal approximation were c=4.005±0.001Å;a=3.995±0.001Å.The presence in the films of small unit cell deformation arising from different unit cells parameters of the film and substrate is observed.Dielectric properties and capacitance-voltage characteristics have been measured.The ellipsometric parameters have been obtained.
