School of Electronic Science and Engineering, Nanjing University, Nanjing, 210093, People's Republic of China. Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing, 210093, People's Republic of China. Jiangsu Provincial Key Laboratory of Photonic and Electronic Materials Sciences and Technology, Nanjing University, Nanjing, 210093, People's Republic of China.
Nanotechnology. 2018 Oct 12;29(41):415701. doi: 10.1088/1361-6528/aad35d. Epub 2018 Jul 13.
Si-based resistive random access memory (RRAM) devices at the nanoscale with high uniformity have great potential applications in the future. We demonstrate that the uniformity evolution of the a-SiN:H RRAM at the low resistance state (LRS) and the high resistance state (HRS) can be clearly monitored by presetting a Si dangling bond (Si-DB) conductive pathway through thermal energy. It is found that the increased magnitude of uniformity for the LRS and the HRS are determined by the number of preset Si-DBs, which can be controlled by tuning thermal energy. As for LRS, the Si-DBs produced under the electric field along with the preset Si-DB conductive pathways form the main conductive pathway. Theoretical calculation of current-voltage (I-V) curves indicates that the Si-DB conductive pathways obey the trap-assisted tunneling model. In the HRS, the preset Si-DBs induced by thermal energy are the unique source of the conductive pathway. The transmission mechanism involves a trap-to-trap process by the hopping of electrons under a low electric field, Poole-Frenkel emission in the main region under the medium electric field and Fowler-Nordheim tunneling under the high electric field. Our discovery of the uniformity evolution for a-SiN:H RRAM device through presetting the Si-DB conductive pathway provides new insight into the resistive switching mechanism of next generation Si-based RRAM devices.
具有高均匀性的硅基阻变随机存取存储器 (RRAM) 器件在未来具有很大的应用潜力。我们证明,通过热能量预先设定 Si 悬挂键 (Si-DB) 导电通路,可以清楚地监测 a-SiN:H RRAM 在低阻状态 (LRS) 和高阻状态 (HRS) 下的均匀性演变。研究发现,LRS 和 HRS 均匀性增加的幅度取决于预设 Si-DB 的数量,而预设 Si-DB 的数量可以通过调节热能量来控制。对于 LRS,电场下产生的 Si-DB 与预设的 Si-DB 导电通路一起形成主要的导电通路。电流-电压 (I-V) 曲线的理论计算表明,Si-DB 导电通路遵循陷阱辅助隧穿模型。在 HRS 中,热能量诱导的预设 Si-DB 是导电通路的唯一来源。传输机制涉及在低电场下电子通过跳跃的陷阱到陷阱过程、在中等电场下主要区域的 Poole-Frenkel 发射以及在高电场下的 Fowler-Nordheim 隧穿。我们通过预设 Si-DB 导电通路发现 a-SiN:H RRAM 器件均匀性的演变,为下一代基于 Si 的 RRAM 器件的电阻开关机制提供了新的见解。