摘要
分别采用sol-gel法和磁控溅射法在Si(001)单晶衬底上制备出(111)和(001)取向的MgO缓冲层薄膜,随后在其上生长Ba0.7Sr0.3TiO3(BST30)铁电薄膜.通过X射线衍射,扫描电子显微镜,原子力显微镜等方法研究了薄膜的微结构.实验结果发现,在较厚的MgO(001)缓冲层上可长出(101)取向的BST30薄膜,而在较薄的MgO(111)缓冲层上则表现出(101)和(111)取向相互竞争的现象,随着MgO(111)缓冲层厚度的增加,BST30薄膜的(101)取向被抑制,而(001)取向逐渐增强.利用反射率测定仪、阻抗分析仪研究了BST30薄膜的光学和电学性能.通过改进的单纯形法拟合反射率曲线,得到了BST30及其MgO缓冲层薄膜的光学常数,由BST30薄膜的电压-电流特性(I-V曲线),发现MgO缓冲层对BST30薄膜的漏电流有明显的阻隔作用,可以有效消除BST30膜层的p-n结效应.
The （001） and （111）-oriented MgO buffer layers, on which ferroelectric Ba0.7Sr0.3TiO3 （BST30） thin films were prepared subsequently, have been grown on Si （001） single-crystal substrates by sol-gel and magnetron sputtering methods. The microstructure of the thin films was investigated by XRD, AFM and SEM. The results showed that the （101）-prefer-oriented BST30 thin film was obtained on the thicker MgO（001） buffer layer, while only the competition between the （101） and （111） orientations of BST30 can be observed on the thinner MgO（111） buffer layer. With the increasing thickness of MgO（ 111 ） buffer layer, the BST30 thin film＇s （101） orientation was restrained, whereas the （001） orientation was strengthened. The improved simplex method was utilized to obtain the optical constant （n） and thickness （d） of BST30 thin film and MgO buffer layer. It was also found that the MgO buffer layer can significantly decrease the leakage current and p-n junction effect of BST30 thin film.
出处
《物理学报》
SCIE
EI
CAS
CSCD
北大核心
2009年第7期5013-5021,共9页
Acta Physica Sinica
基金
国家自然科学基金(批准号:60578012)
浙江省自然科学基金(批准号:X405002)资助的课题~~
