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利用溶胶-凝胶法成功制备了Mg掺杂Pb0.4Sr0.6MgxTi1-xO3-x薄膜,利用x射线衍射仪对薄膜的物相和结构进行了分析,用扫描电子显微镜对薄膜的形貌和断面等进行了观察.研究结果表明,薄膜以立方钙钛矿为晶相,薄膜中晶相以团聚状颗粒存在,晶相含量受热处理条件和Mg的掺杂量所控制.Mg掺杂对Pb0.4Sr0.6MgxTi1-xO3-x薄膜晶相含量的影响与钙钛矿中的氧空位缺陷相关.在一定的掺杂范围内,由掺杂引起晶相的晶格畸变较小时,体系掺Mg平衡了晶体内本征氧空位引入的电荷不平衡,使晶相更为稳定,析晶能力提高,晶体形成量随掺杂浓度的提高而提高.当掺杂浓度达到一定量时,随着Mg掺杂浓度增加,一方面使形成晶体时杂质浓度增加造成参与形成晶相的组成含量下降,另一方面使进入钙钛矿结构的Mg增加,氧空位大量增加使畸变程度提高,形成的晶相不稳定,析晶能力下降,晶体含量随掺杂Mg浓度的增加而不增反降.在相同条件下制备的Pb0.4Sr0.6MgxTi1-xO3-x薄膜中Mg掺量约为x=0.01时,得到的钙钛矿相含量最高,本征氧缺陷所带入的正电荷和Mg引入时带入的负电荷间达到平衡.此外,Mg的掺入还影响到析晶与热处理过程之间的关系.在高Mg掺量范围,Mg含量越高,形成的晶相越不稳定,热处理时间越长,使热处理过程中分解的晶相量越多,随Mg掺量越高和热处理时间越长,薄膜中晶相含量越低.
The Mg-doped Pb0.4Sr0.6MgxTi1-xO3-x thin films were successfully prepared by sol-gel method. The phase and structure of the films were analyzed by x-ray diffractometer. The morphology and cross section of the films were observed by scanning electron microscopy Etc. The results show that the film is cubic perovskite crystal phase, the crystal phase in the film as agglomerated particles exist, the crystal phase content is controlled by the heat treatment conditions and Mg doping amount. Mg doping Pb0. The influence of the crystal phase content of 4Sr0.6MgxTi1-xO3-x thin films on the oxygen vacancies in the perovskite is related to that the Mg doping is balanced in a certain doping range when the crystal lattice distortion is small due to doping The imbalanced charge introduced by the intrinsic oxygen vacancies in the crystal makes the crystal phase more stable, the ability of crystallization increases, and the amount of crystal formation increases with the increase of the doping concentration.When the doping concentration reaches a certain amount, On the other hand, the content of Mg in the perovskite structure increases and the oxygen vacancies increase greatly to increase the degree of distortion, and the crystal phase formed is not stable , Crystallization ability decreased, the crystal content with doping Mg concentration without increasing anti-drop.The Pb content in Pb0.4Sr0.6MgxTi1-xO3-x thin films prepared under the same conditions is about x = 0.01, the content of perovskite phase is the highest, the intrinsic oxygen defect The positive charge brought in and the negative charge brought in by the introduction of Mg reach a balance between them.In addition, the incorporation of Mg also affects the relationship between the crystallization and the heat treatment process.In the high Mg content range, the higher the Mg content, The more unstable the crystal phase, the longer the heat treatment time, the more the amount of crystal phase decomposed during the heat treatment. The higher the Mg content and the longer the heat treatment time, the lower the crystal phase content in the film.