近日，加拿大麦吉尔大学的Megan Cowie及其研究团队取得一项新进展。经过不懈努力，他们对Si/SiO₂界面处单一势阱的空间分辨随机电报涨落进行研究。相关研究成果已于2024年10月24日在国际知名学术期刊《美国科学院院刊》上发表。

该研究团队利用静电力显微镜对Si/SiO₂界面处的随机电报噪声进行了空间分辨。测量结果表明，两态波动定位于界面陷阱处，其速率和振幅均依赖于偏置电压。这些两能级系统导致载流子数量和迁移率波动在一系列特征时间尺度上呈现相关性；当它们作为一个整体时，会产生1/f的功率谱趋势。

Si/SiO₂界面处的这种单一缺陷涨落会损害纳米级半导体器件的性能和可靠性，并将成为基于半导体的量子传感器和计算机中的一个重要噪声来源。此处测量到的涨落与四种速率的竞争有关，包括秒级慢速两态切换，以及在其中一种状态下与能量损失相关的纳秒级快速切换。

附：英文原文

Title: Spatially resolved random telegraph fluctuations of a single trap at the Si/SiO₂ interface

Author: Cowie, Megan, Constantinou, Procopios C., Curson, Neil J., Stock, Taylor J. Z., Grütter, Peter

Issue&Volume: 2024-10-24

Abstract: We use electrostatic force microscopy to spatially resolve random telegraph noise at the Si/SiO₂ interface. Our measurements demonstrate that two-state fluctuations are localized at interfacial traps, with bias-dependent rates and amplitudes. These two-level systems lead to correlated carrier number and mobility fluctuations with a range of characteristic timescales; taken together as an ensemble, they give rise to a 1/f power spectral trend. Such individual defect fluctuations at the Si/SiO₂ interface impair the performance and reliability of nanoscale semiconductor devices and will be a significant source of noise in semiconductor-based quantum sensors and computers. The fluctuations measured here are associated with a four-fold competition of rates, including slow two-state switching on the order of seconds and, in one state, fast switching on the order of nanoseconds which is associated with energy loss.

DOI: 10.1073/pnas.2404456121

Source: https://www.pnas.org/doi/abs/10.1073/pnas.2404456121