Grain boundary composition and conduction in HfO2: An ab initio study
Grain boundary composition and conduction in HfO2: An ab initio study
复制标题
DOI：
10.1063/1.4807666
复制
发表时间：
2013-05
影响因子：
4
通讯作者：
K. Xue;P. Blaise;L. Fonseca;G. Molas;E. Vianello;B. Traoré;B. D. Salvo;G. Ghibaudo;Y. Nishi
中科院分区：
文献类型：
--
作者：
K. Xue;P. Blaise;L. Fonseca;G. Molas;E. Vianello;B. Traoré;B. D. Salvo;G. Ghibaudo;Y. Nishi
采用基于立方相的简单Σ5(3 10)/[0 0 1]晶界模型研究了HfO2晶界的电子性质。我们的计算表明，由于某些Hf离子在晶界的配位不足，在导带下方出现了0.4 eV的空缺陷态。它们还表明，Hf和Ti等金属间隙向晶界的迁移在能量上是有利的，使晶界区域金属化。这种情况可能在多晶HfO2中产生漏电路径，或者用作阻性随机存取存储器中的传导机制。
We investigate the electronic properties of HfO2 grain boundaries employing a simple Σ5 (310)/[001] grain boundary model based on the cubic phase. Our calculations show the emergence of unoccupied defect states 0.4 eV below the conduction band due to the under-coordination of certain Hf ions in the grain boundary. They also show that migration of metal interstitials such as Hf and Ti to the grain boundary is energetically favorable, turning the grain boundary region metallic. This scenario may create leakage paths in poly-crystalline HfO2 or serve as the conduction mechanism in resistive random access memories.