BixLa1-xFeO3薄膜的介电和铁电性质的研究

Study on Dielectric and Ferroelectric Properties of BixLa1-xFeO3 Film

用溶胶-凝胶法制备了纯的和5％La掺杂的BiFeO3薄膜，研究了室温下薄膜的介电和铁电性质。介质性质研究表明，在6．8MHz和7．8MHz附近，BiFeO3薄膜和Bi0．95La0．05FeO3薄膜分别出现了介电损耗极大和介电常数的正负转变，归结为薄膜的介电性质由容性向感性的转化。而铁电测试表明，通过La掺杂，增强了薄膜的铁电性，同时有效地减少了BiFeO3薄膜的漏导。

Pure and 5 % La-doped BiFeO3 films are prepared by sol-gel process, the ferroelectric and dielectric properties are studied at room temperature. The study of dielectric property shows that the BiFeO3 film and the Bi0.95 La0.05FeO3 film show maximum dielectric dissipation and the transition dielectric constant between positive value and negative value at the frequency of 6. 8MHz and 7.8MHz respectively, which are ascribed to the transition between capacitive dielectric property and inductive dielectric property. The results of ferroelectriity test show that there is an improvement in ferroeoectricity and reduction of leakage conduction by doping La.