Enhancement of resistive switching under confined current path distribution enabled by insertion of atomically thin defective monolayer graphene

Keundong Lee, Inrok Hwang, Sangik Lee, Sungtaek Oh, Dukhyun Lee, Cheol Kyeom Kim, Yoonseung Nam, Sahwan Hong, Chansoo Yoon, Robert B. Morgan, Hakseong Kim, Sunae Seo (+3 others)
2015 Scientific Reports  
Resistive random access memory (ReRAM) devices have been extensively investigated resulting in significant enhancement of switching properties. However fluctuations in switching parameters are still critical weak points which cause serious failures during 'reading' and 'writing' operations of ReRAM devices. It is believed that such fluctuations may be originated by random creation and rupture of conducting filaments inside ReRAM oxides. Here, we introduce defective monolayer graphene between an
more » ... oxide film and an electrode to induce confined current path distribution inside the oxide film, and thus control the creation and rupture of conducting filaments. The ReRAM device with an atomically thin interlayer of defective monolayer graphene reveals much reduced fluctuations in switching parameters compared to a conventional one. Our results demonstrate that defective monolayer graphene paves the way to reliable ReRAM devices operating under confined current path distribution. Nowadays one of the most widely used nonvolatile memories is flash memory. It has been employed to numerous mobile devices and becomes a representative product supplied by the Si based semiconductor industries. The flash memory is expected to reach limitations in operating speed, power consumption, and density of memory in near future because it is a charge-storage type memory based on a Si transistor. To overcome the limitations, many researchers have tried to develop next generation nonvolatile memories (NG-NVM) with high performances, which do not rely on stored charges and Si transistors 1-4 . ReRAM whose resistive change is induced by applied external electrical stress is considered as one of these NG-NVMs. In addition to the advantageous properties of oxide-based ReRAM such as simple composition, facile fabrication process, and compatibility with conventional semiconductor processes, this resistance-change memory has presented promising nonvolatile memory effects including fast operation speed, low power consumption, and high scalability 5-9 . Resistive switching can be classified into two categories: Uni-polar and bi-polar resistive switching caused by conducting filament formation in bulk and oxygen migration at interface, respectively. Especially, uni-polar resistive switching, which is usually observed in binary oxide, has been explained
doi:10.1038/srep11279 pmid:26161992 pmcid:PMC4498384 fatcat:c6avn7dnqfd2bhnuhefvtzuyna