利用电子全息术测量掺锰钛酸锶双晶界面的势场分布  

Determination of potential distribution at grain boundary of strontium titanate bicrystals doped with manganese using electron holograph

作　　者：王岩国[1] 张泽[1] 阎光辉[2] 

机构地区：[1]中国科学院物理研究所北京电子显微镜实验室,北京100080 [2]辽宁大学物理系,沈阳110036

出　　处：《电子显微学报》2001年第2期121-126,共6页Journal of Chinese Electron Microscopy Society

基　　金：中国科学院北京物质科学基地资助项目

摘　　要：用电子全息方法测量了掺锰钛酸锶 2 4°[0 0 1]倾转晶界面的电势场分布。该势场分布特征是以界面为中心的双Schottky势垒。利用Poisson方程由势场分布导出了电荷在界面处的分布。特征是界面中心处有负电荷集聚 ,相邻空间分布着等量的正电荷使得该界面在整体上保持电中性。势场分布的宽度约为 3nm。导致Schottky势垒产生的原因是界面上发生了Mn+2 及Mn+3 离子与Ti+4 离子间的替代反应 ,使得电子在界面处聚集 ,Ti+4Potential distribution of 24°[001] tilt boundary of strontium titanate doped with manganese was measured using electron holograph. Characteristic of the potential coincided to double Schottky barriers with the center located at the boundary. Distribution of charge density with the major feature of negative charge concentrated at the boundary surrounded by positive space charges, which kept the boundary to be electrical neutrality, was analyzed to be within a dimension of 3nm using Poisson′s equation. Genetic aspect of the detected potential resulted from substitution of Mn +2 and Mn +3 for Ti +4 , which resulted in concentrition of electrons at the boundary and Ti +4 cations mainly located at the nearby spaces.

关 键 词：电子全息 钛酸锶 铁电材料 掺杂 双晶界面 势场分布 

分 类 号：TM28[一般工业技术—材料科学与工程]