Department of Materials Science and Engineering, Pohang University of Science and Technology (POSTECH) , Pohang 790-784, Republic of Korea.
ACS Nano. 2016 May 24;10(5):5413-8. doi: 10.1021/acsnano.6b01643. Epub 2016 Apr 19.
Active research has been done on hybrid organic-inorganic perovskite materials for application to solar cells with high power conversion efficiency. However, this material often shows hysteresis, which is undesirable, shift in the current-voltage curve. The hysteresis may come from formation of defects and their movement in perovskite materials. Here, we utilize the defects in perovskite materials to be used in memory operations. We demonstrate flexible nonvolatile memory devices based on hybrid organic-inorganic perovskite as the resistive switching layer on a plastic substrate. A uniform perovskite layer is formed on a transparent electrode-coated plastic substrate by solvent engineering. Flexible nonvolatile memory based on the perovskite layer shows reproducible and reliable memory characteristics in terms of program/erase operations, data retention, and endurance properties. The memory devices also show good mechanical flexibility. It is suggested that resistive switching is done by migration of vacancy defects and formation of conducting filaments under the electric field in the perovskite layer. It is believed that organic-inorganic perovskite materials have great potential to be used in high-performance, flexible memory devices.
人们对用于高效太阳能电池的杂化有机-无机钙钛矿材料进行了大量研究。然而,这种材料通常表现出不理想的滞后现象,即电流-电压曲线发生偏移。滞后可能源于钙钛矿材料中缺陷的形成及其在其中的移动。在这里,我们利用钙钛矿材料中的缺陷来进行存储操作。我们展示了基于杂化有机-无机钙钛矿的柔性非易失性存储器器件,该器件将其作为阻变层构筑在塑料衬底上。通过溶剂工程,在透明电极涂覆的塑料衬底上形成了均匀的钙钛矿层。基于钙钛矿层的柔性非易失性存储器在编程/擦除操作、数据保持和耐久性方面表现出可重复且可靠的存储特性。该存储器件还表现出良好的机械柔韧性。据认为,阻变是通过钙钛矿层中的空位缺陷的迁移以及在电场下形成的导电细丝来实现的。相信有机-无机钙钛矿材料在高性能、柔性存储器件中有很大的应用潜力。