期刊
PHYSICAL REVIEW B
卷 82, 期 1, 页码 -出版社
AMER PHYSICAL SOC
DOI: 10.1103/PhysRevB.82.014116
关键词
-
资金
- National Hi-tech (R&D) Project of China [2007AA03Z426, 2009AA034001]
- National Natural Science Foundation of China [50871060, 50772055]
- National Basic Research Program of China [2010CB832905]
To investigate the relationship between the electromechanical response, d(33), of doped ZnO and the dopant ionic size, the chemical state and ionic size of Fe in Fe-ZnO films were modulated through doping with various Fe concentrations and postannealing. We found that an enhanced d(33) of more than 110 pC/N is obtained in Fe-ZnO films when Fe3+ with an ionic radius of 0.64 angstrom substitutes for the Zn2+ (0.74 angstrom) site. The d(33) (less than 7 pC/N) is smaller than that of undoped ZnO films (11.6 pC/N) when Fe2+ (0.76 angstrom) substitutes for Zn2+. The enhanced electromechanical response is ascribed to polarization rotation induced by the external electric field. The microscopic origin is considered. Substitution of Fe3+ with smaller ionic size for Zn2+ results to the easier rotation of noncollinear Fe-O1 bonds along the c axis under the applied field. Thus, the external electric field needed for polarization rotation is smaller. When bigger Fe2+ substitutes for Zn2+, rotation of Fe-O1 bonds becomes more difficult and thus the d(33) is smaller. A general mechanism is derived. Doping ZnO with a small ion produces enhanced electromechanical responses whereas doping ZnO with a big ion results in decreased electromechanical responses. This mechanism is useful for guiding the design of new wurtzite semiconductors with enhanced electromechanical responses.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据