摘要:
采用异质叠层方式制备出一定厚度的Ca(Mg_(1/3)Nb_(2/3))O_3/CaTiO_3(CMN/CT)叠层薄膜,研究了异质界面对薄膜结构、微观形貌及介电性能的影响及其规律.根据实验测试结果,提出CMN/CT叠层薄膜的模拟等效电路,建立介电常数和介电损耗的理论计算公式.结果表明:CMN/CT异质叠层薄膜具有完全正交钙钛矿结构,结构致密,厚度均匀,薄膜中存在独立的CMN和CT相.异质界面处存在过渡层,随着薄膜中异质界面个数增加,介电常数增大,介电损耗减小.减小界面过渡层的厚度,有利于提高CMN/CT叠层薄膜的介电性能.
Abstract:
The effects of heterogeneous interfaces on the microstructure,the morphology and the dielectric properties of Ca(Mg_(1/3)Nb_(2/3))O_3/CaTiO_3(CMN/CT) multilayered(ML) thin film prepared in the layer-by-layer mode with a certain thickness are investigated.According to the experimental results,an equivalent circuit of CMN/CT ML thin film is simulated,and the theoretical formulae of the dielectric constant and loss of thin film are established.The results indicate that CMN/CT ML thin film,in which CT and CMN phases can exist independently,possesses a pure orthorhombic perovskite structure,dense smooth surfaces and intermediate layers at the heterogeneous interfaces,and that the dielectric constant increases and the dielectric loss decreases with the increase in the number of heterogeneous interfaces,and reducing the thickness of the interfacial transition layer is useful to improve the dielectric properties of CMN/CT multilayered thin film.