Kim Kwang-Hyun, Park Youngjun, Kim Min-Kyu, Lee Jang-Sik
Department of Materials Science and Engineering, Pohang University of Science and Technology (POSTECH), Pohang, 37673, Korea.
Small. 2021 Jul;17(29):e2100401. doi: 10.1002/smll.202100401. Epub 2021 Jun 9.
Atomic switch-based selectors, which utilize the formation of conductive filaments by the migration of ions, are researched for cross-point array architecture due to their simple structure and high selectivity. However, the difficulty in controlling the formation of filaments causes uniformity and reliability issues. Here, a multilayer selector with Pt/Ag-doped ZnO/ZnO/Ag-doped ZnO/Pt structure by the sputtering process is presented. A multilayer structure enables control of the filament formation by preventing excessive influx of Ag ions. The multilayer selector device exhibits a high on-current density of 2 MA cm , which can provide sufficient current for the operation with the memory device. Also, the device exhibits high selectivity of 10 and a low off-current of 10 A. The threshold voltage of selector devices can be controlled by modulating the thickness of the ZnO layer. By connecting a multilayer selector device to a resistive switching memory, the leakage current of the memory device can be reduced. These results demonstrate that a multilayer structure can be used in a selector device to improve selectivity and reliability for use in high-density memory devices.
基于原子开关的选择器利用离子迁移形成导电细丝，因其结构简单且选择性高而被用于交叉点阵列架构的研究。然而，控制细丝形成的困难导致了均匀性和可靠性问题。在此，通过溅射工艺展示了一种具有Pt/Ag掺杂的ZnO/ZnO/Ag掺杂的ZnO/Pt结构的多层选择器。多层结构通过防止Ag离子的过度流入来实现对细丝形成的控制。该多层选择器器件展现出2 MA/cm²的高导通电流密度，可为与存储器件协同工作提供足够的电流。此外，该器件具有10的高选择性和10 A的低关断电流。选择器器件的阈值电压可通过调制ZnO层的厚度来控制。通过将多层选择器器件连接到电阻式开关存储器，可降低存储器件的漏电流。这些结果表明，多层结构可用于选择器器件，以提高其选择性和可靠性，从而应用于高密度存储器件。
