MOSFET中大幅度随机电报信号噪声的动力学特性

对 MOSFET器件的随机电报信号噪声 ( RTS)的特征进行了研究。室温下在极细沟道样品中观测到了大幅度 (大于 60 % )的 RTS,通过测量 RTS的俘获时间和发射时间与栅压和温度的依赖关系 ,获得了氧化层陷阱的位置与能级 ,证实了氧化层陷阱的热激活模型在细沟道 n MOSFET中仍然成立。同时发现当器件工作在弱反型区时 ,RTS幅度基本与栅压无关。对 RTS的动力学机制的分析及数值模拟表明 ,当沟道宽度减小至 4 0 nm以下时 ,由荷电陷阱对沟道载流子散射而产生的迁移率涨落对 RTS的幅度的影响起主导作用。

Dynamic Characteristics of Large Amplitude Random Telegraph Signals in MOSFETs

Dynamic characteristics of random telegraph signals (RTSs) in MOSFETs have been investigated, RTS with very large amplitude (>60%) has been observed at room temperature for the first time. The position and energy level of the activated oxide trap are determined by measuring the dependence of capture time and emission time on gate bias voltage. Thermal activated model has also been confirmed in n MOSFETs with very narrow channels. Furthermore, the amplitude of RTS is found almost independent of gate bias voltage. The observations suggest that the fluctuation of carrier mobility play a predominant role as the channel width is reduced below 40 nm, which is confirmed by numerical simulation.