LaNiO_3缓冲层对化学溶液法制备的Pb(Mg_(1/3)Nb_(2/3))O_3-PbTiO_3薄膜的结构与电学性能的影响

Effect of LaNiO_3 Buffer Layer on the Structure and Electrical Properties of Pb(Mg_(1/3)Nb_(2/3))O_3-PbTiO_3 Thin Films Deposited by Chemical Solution Method

采用化学溶液法在Pt/TiO2/SiO2/Si衬底上制备了92%Pb(Mg1/3Nb2/3)O3-8%PbTiO3(PMNT)薄膜,对于在衬底上引入缓冲层LaNiO3(LNO)和没有引入缓冲层LNO所制备的PMNT薄膜结构及电学性能进行了比较和研究。X射线衍射测试结果表明:直接在Pt/TiO2/SiO2/Si衬底上所制备的PMNT薄膜含有大量的烧绿石相,且薄膜呈现高度的(111)择优取向;而当在Pt/TiO2/SiO2/Si衬底上引入LNO缓冲层后,所制备的PMNT薄膜是纯钙钛矿相,且薄膜呈现(100)择优取向。通过铁电和介电性能测试表明:当在Pt/TiO2/SiO2/Si衬底上引入缓冲层LNO后,所制备的PMNT薄膜的剩余极化和介电常数也都得到了较大提高。

92% Ph（ Mg1/3 Nb2/3 ）O3-8% PbTiO3 （PMNT） thin films on Pt/TiO2/SiO2/Si substrates with and without a LaNiO3 （LNO） buffered layer have been prepared using chemical solution method. Structures and electrical properties of the films have been investigated and compared. Highly （ 111 ）- oriented PMNT thin films with some amounts of pyrochlore phase are obtained on bare Pt electrodes. On the contrary, （100）-oriented PMNT thin films with pure perovskite phase are formed on Pt electrodes with a LNO buffered layer. Electrical properties of the PMNT thin films are highly improved by using the buffered layer LNO. It is found that the remanent polarization （Pr） and the dielectric constant for the PMNT film with a LNO buffered layer are larger than that for the film without a LNO buffered layer.