Ge Ni-Na, Gong Chuan-Hui, Yuan Xin-Cai, Zeng Hui-Zhong, Wei Xian-Hua
State Key Laboratory of Environment-friendly Energy Materials, Southwest University of Science and Technology Mianyang 621010 P. R. China
State Key Laboratory of Electronic Thin Films and Integrated Devices, University of Electronics Science and Technology of China Chengdu 610054 P. R. China.
RSC Adv. 2018 Aug 20;8(52):29499-29504. doi: 10.1039/c8ra04784g.
We investigated the bipolar resistive switching (BRS) properties of Mn-doped NiO thin films by sol-gel spin-coating. As the Mn doping concentration increased, lattice constant, grain size and band gap were found to decrease simultaneously. Moreover, the electroforming voltages and threshold voltages were gradually reduced. It can be ascribed to the increase in the density of grain boundaries, and the defects caused by doping Mn and lower formation energy of Mn-O. They would be helpful for the formation of oxygen vacancies and conductive filaments. It is worth mentioning that excellent BRS behaviors can be obtained at a low Mn-doped concentration including enlarged ON/OFF ratio, good uniformity and stability. Compared with other samples, the 1% Mn-doped NiO showed the highest ON/OFF ratio (>10), stable endurance of >100 cycles and a retention time of >10 s. The mechanism should be determined by bulk properties rather than the dual-oxygen reservoir structure. These results indicate that appropriate Mn doping can be applied to improve the BRS characteristics of NiO thin films, and provide stable, low-power-consumption memory devices.
我们通过溶胶-凝胶旋涂法研究了锰掺杂氧化镍（NiO）薄膜的双极电阻开关（BRS）特性。随着锰掺杂浓度的增加，发现晶格常数、晶粒尺寸和带隙同时减小。此外，电形成电压和阈值电压逐渐降低。这可归因于晶界密度的增加、锰掺杂引起的缺陷以及MnO的形成能较低。它们有助于氧空位和导电细丝的形成。值得一提的是，在低锰掺杂浓度下可获得优异的BRS行为，包括增大的开/关比、良好的均匀性和稳定性。与其他样品相比，1%锰掺杂的NiO表现出最高的开/关比（>10）、>100次循环的稳定耐久性和>10秒的保持时间。其机制应由体相性质而非双氧储库结构决定。这些结果表明，适当的锰掺杂可用于改善NiO薄膜的BRS特性，并提供稳定、低功耗的存储器件。
