Hong Seung Hui, Kim Min Choul, Jeong Pil Seong, Choi Suk-Ho, Kim Kyung Joong
Department of Applied Physics, College of Electronics and Information, Kyung Hee University, Yongin 449-701, Korea.
Nanotechnology. 2008 Jul 30;19(30):305203. doi: 10.1088/0957-4484/19/30/305203. Epub 2008 Jun 12.
1-5 period multilayers of Ge nanodots (NDs) for nonvolatile memories have been self-assembled by ion beam sputtering deposition of an ultra-small amount of Ge between SiO(2) layers at room temperature without post-annealing. High-resolution transmission electron microscopy demonstrates the existence of Ge ND layers well defined with respect to the SiO(2)/Si interface. The memory window that is estimated by capacitance-voltage hysteresis is proportional to the period, and finally reaches a plateau of about 11 V asymptotically over three periods. The program speed is enhanced over the full pulse-time range by increasing bias voltage or period. The charge-loss speed in the programmed state is slower in the samples with larger period. These memory properties are discussed based on possible physical mechanisms.
通过在室温下在SiO₂层之间离子束溅射沉积超少量Ge，在不进行后退火的情况下自组装了用于非易失性存储器的1 - 5周期多层锗纳米点（NDs）。高分辨率透射电子显微镜表明，相对于SiO₂/Si界面，锗纳米点层的存在清晰可辨。通过电容 - 电压滞后估计的存储窗口与周期成正比，最终在三个周期内渐近达到约11 V的平稳值。通过增加偏置电压或周期，在整个脉冲时间范围内编程速度得到提高。在周期较大的样品中，编程状态下的电荷损失速度较慢。基于可能的物理机制对这些存储特性进行了讨论。
