Non-linear current–voltage characteristics related to native defects in SrTiO3 and ZnO bicrystals
Non-linear current–voltage characteristics related to native defects in SrTiO3 and ZnO bicrystals
复制标题
与 SrTiO3 和 ZnO 双晶固有缺陷相关的非线性电流-电压特性
DOI：
10.1016/j.stam.2003.10.031
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发表时间：
2003
影响因子：
5.5
通讯作者：
T. Sakuma
中科院分区：
文献类型：
--
作者：
Y. Sato;Tomohito Tanaka;F. Oba;Takahisa Yamamoto;Y. Ikuhara;T. Sakuma
制备了具有不同晶界类型的SrTiO 3和ZnO双晶，研究了它们在单晶界上的电流-电压特性。用高分辨透射电子显微镜研究了它们的晶界结构。在Nb掺杂的SrTiO 3中，电子输运行为依赖于晶界的类型。随机型边界表现出高度非线性的电流-电压特性，而小角度边界表现出轻微的非线性。相反，未掺杂的ZnO不表现出非线性的电流-电压特性，在任何类型的边界，包括随机的。这表明，观察到的两个系统之间的电流-电压特性的差异，主要是由于在晶界上的受主类本征缺陷的积累行为的差异。一个明确的非线性得到通过Co掺杂，即使是在ZnO双晶体中的高度相干的B1边界。这被认为是由于共掺杂产生的受体样的原生缺陷。
SrTiO 3 and ZnO bicrystals with various types of boundaries were fabricated in order to examine their current–voltage characteristics across single grain boundaries. Their grain boundary structures were also investigated by high-resolution transmission electron microscopy. In Nb-doped SrTiO 3, electron transport behaviors depend on the type of boundaries. Random type boundaries exhibit highly non-linear current–voltage characteristics, while low angle boundaries show a slight non-linearity. On the contrary, undoped ZnO does not exhibit non-linear current–voltage characteristics in any type of boundaries including random ones. It is suggested that the differences observed in current–voltage properties between the two systems are mainly due to the difference in the accumulation behavior of acceptor-like native defects at grain boundaries. A clear non-linearity is obtained by means of Co-doping even for the highly coherent Σ1 boundary in a ZnO bicrystal. This is considered to result from the production of acceptor-like native defects by Co-doping.