With the use of techniques of SawyerTower and Mertz method regularities of the origin of "fatigue"in thin ferroelectric films of lead titanate and lead zirconate titanate have been investigated in the field...With the use of techniques of SawyerTower and Mertz method regularities of the origin of "fatigue"in thin ferroelectric films of lead titanate and lead zirconate titanate have been investigated in the fields above coercive.We propose a model to explain the experimentally observed switching-dependent fatigue processes by the motion of charged dislocations in an applied external alternating electric field.展开更多
The paper presents the structural and ferroelectric results for Sr_(1-x)Ba_(x)Bi_(2)Nb_(2)O_(9)(x=0.30;0.85)thin films,which were obtained by using dip-coating.The solutions containing the desirable ions were prepared...The paper presents the structural and ferroelectric results for Sr_(1-x)Ba_(x)Bi_(2)Nb_(2)O_(9)(x=0.30;0.85)thin films,which were obtained by using dip-coating.The solutions containing the desirable ions were prepared from the powders of the previous studied ceramic samples.The films were deposited at room temperature on Fluorine-doped Tin Oxide(FTO)substrates and submitted to a heat treatment for crystallization.The films were characterized by using scanning microscopy electronic,energy dispersive spectroscopy and ellipsometry.Hysteresis ferroelectric loops were obtained,at room temperature,by using a Sawyer-Tower circuit at several frequencies.A well-defined grain structure was observed for both compositions.The energy dispersive spectroscopy(EDS)measurements revealed the presence of the corresponding elements from the chemical composition of the ceramic systems.The band-gap energy was around 3.3 eV for both samples.Typical hysteresis loops for normal and relaxor ferroelectrics were obtained for x=0.30 and 0.85,respectively.展开更多
文摘With the use of techniques of SawyerTower and Mertz method regularities of the origin of "fatigue"in thin ferroelectric films of lead titanate and lead zirconate titanate have been investigated in the fields above coercive.We propose a model to explain the experimentally observed switching-dependent fatigue processes by the motion of charged dislocations in an applied external alternating electric field.
基金the Third World Academy of Sciences(RG/PHYS/LA Nos.99-050,02-225 and 05-043)to the ICTP,Trieste-Italy,for financial support of Latin-American Network of Ferroelectric Materials(NET-43,currently NT-02).
文摘The paper presents the structural and ferroelectric results for Sr_(1-x)Ba_(x)Bi_(2)Nb_(2)O_(9)(x=0.30;0.85)thin films,which were obtained by using dip-coating.The solutions containing the desirable ions were prepared from the powders of the previous studied ceramic samples.The films were deposited at room temperature on Fluorine-doped Tin Oxide(FTO)substrates and submitted to a heat treatment for crystallization.The films were characterized by using scanning microscopy electronic,energy dispersive spectroscopy and ellipsometry.Hysteresis ferroelectric loops were obtained,at room temperature,by using a Sawyer-Tower circuit at several frequencies.A well-defined grain structure was observed for both compositions.The energy dispersive spectroscopy(EDS)measurements revealed the presence of the corresponding elements from the chemical composition of the ceramic systems.The band-gap energy was around 3.3 eV for both samples.Typical hysteresis loops for normal and relaxor ferroelectrics were obtained for x=0.30 and 0.85,respectively.
