The two-dimensional models for symmetrical double-material double-gate (DM-DG) strained Si (s-Si) metal-oxide semiconductor field effect transistors (MOSFETs) are presented. The surface potential and the surface...The two-dimensional models for symmetrical double-material double-gate (DM-DG) strained Si (s-Si) metal-oxide semiconductor field effect transistors (MOSFETs) are presented. The surface potential and the surface electric field ex- pressions have been obtained by solving Poisson's equation. The models of threshold voltage and subthreshold current are obtained based on the surface potential expression. The surface potential and the surface electric field are compared with those of single-material double-gate (SM-DG) MOSFETs. The effects of different device parameters on the threshold voltage and the subthreshold current are demonstrated. The analytical models give deep insight into the device parameters design. The analytical results obtained from the proposed models show good matching with the simulation results using DESSIS.展开更多
以屏蔽栅沟槽(SGT)MOSFET为研究对象,研究了重离子诱发的单粒子微剂量效应的现象及物理机理。对不同偏置电压下的30 V SGT MOSFET进行重离子辐照试验,分析了重离子轰击后器件转移特性曲线的变化趋势,揭示单粒子微剂量效应的退化规律。...以屏蔽栅沟槽(SGT)MOSFET为研究对象,研究了重离子诱发的单粒子微剂量效应的现象及物理机理。对不同偏置电压下的30 V SGT MOSFET进行重离子辐照试验,分析了重离子轰击后器件转移特性曲线的变化趋势,揭示单粒子微剂量效应的退化规律。研究发现重离子入射会引起器件的亚阈值电流增大,导致阈值电压负向漂移,且负栅压下器件的亚阈值电压负向漂移更严重。试验结果结合TCAD仿真进一步揭示在栅氧化层侧墙处Si/SiO_(2)界面的带正电的氧化物陷阱电荷是导致器件阈值电压和亚阈值电压等参数退化的主要原因。研究结果可为SGT MOSFET单粒子微剂量效应评估和建模提供指导。展开更多
With the need to improvement of speed of operation and the demand of low power MOSFET size scales down, in this paper, a 50 nm gate length n-type doped channel MOS (NMOS) is simulated using ATLAS packages of Silv...With the need to improvement of speed of operation and the demand of low power MOSFET size scales down, in this paper, a 50 nm gate length n-type doped channel MOS (NMOS) is simulated using ATLAS packages of Silvaco TCAD Tool so as to observe various electrical parameters at this gate length. The parameters under investigation are the threshold voltage, subthreshold slope, on-state current, leakage current and drain induced barrier lowering (DIBL) by varying channel doping concentration, drain and source doping concentration and gate oxide thickness.展开更多
The impact of quantum confinement on the electrical characteristics of ultrathin-channel GeO1 n- MOSFETs is investigated on the basis of the density-gradient model in TCAD software. The effects of the channel thickne...The impact of quantum confinement on the electrical characteristics of ultrathin-channel GeO1 n- MOSFETs is investigated on the basis of the density-gradient model in TCAD software. The effects of the channel thickness (Tch) and back-gate bias (Vbg) on the electrical characteristics of GeOI MOSFETs are examined, and the simulated results are compared with those using the conventional semi-classical model. It is shown that when T^h 〉 8 rim, the electron conduction path of the GeOI MOSFET is closer to the front-gate interface under the QC model than under the CL model, and vice versa when Tch 〈 8 rim. Thus the electrically controlled ability of the front gate of the devices is influenced by the quantum effect. In addition, the quantum-mechanical mechanism will enhance the drain-induced barrier lowering effect, increase the threshold voltage and decrease the on-state current; for a short channel length (≤ 30 nm), when Tch 〉 8 nm (or 〈 8 nm), the quantum-mechanical mechanism mainly impacts the subthreshold slope (or the threshold voltage). Due to the quantum-size effect, the off-state current can be suppressed as the channel thickness decreases.展开更多
基金Project supported by the National Natural Science Foundation of China(Grant Nos.61376099,11235008,and 61205003)
文摘The two-dimensional models for symmetrical double-material double-gate (DM-DG) strained Si (s-Si) metal-oxide semiconductor field effect transistors (MOSFETs) are presented. The surface potential and the surface electric field ex- pressions have been obtained by solving Poisson's equation. The models of threshold voltage and subthreshold current are obtained based on the surface potential expression. The surface potential and the surface electric field are compared with those of single-material double-gate (SM-DG) MOSFETs. The effects of different device parameters on the threshold voltage and the subthreshold current are demonstrated. The analytical models give deep insight into the device parameters design. The analytical results obtained from the proposed models show good matching with the simulation results using DESSIS.
基金Supported by the National Natural Science Foundation of China(No.60576066,No.60644007)the Natural Science Foundation of Anhui Province(No.2006kj012a).
文摘以屏蔽栅沟槽(SGT)MOSFET为研究对象,研究了重离子诱发的单粒子微剂量效应的现象及物理机理。对不同偏置电压下的30 V SGT MOSFET进行重离子辐照试验,分析了重离子轰击后器件转移特性曲线的变化趋势,揭示单粒子微剂量效应的退化规律。研究发现重离子入射会引起器件的亚阈值电流增大,导致阈值电压负向漂移,且负栅压下器件的亚阈值电压负向漂移更严重。试验结果结合TCAD仿真进一步揭示在栅氧化层侧墙处Si/SiO_(2)界面的带正电的氧化物陷阱电荷是导致器件阈值电压和亚阈值电压等参数退化的主要原因。研究结果可为SGT MOSFET单粒子微剂量效应评估和建模提供指导。
文摘With the need to improvement of speed of operation and the demand of low power MOSFET size scales down, in this paper, a 50 nm gate length n-type doped channel MOS (NMOS) is simulated using ATLAS packages of Silvaco TCAD Tool so as to observe various electrical parameters at this gate length. The parameters under investigation are the threshold voltage, subthreshold slope, on-state current, leakage current and drain induced barrier lowering (DIBL) by varying channel doping concentration, drain and source doping concentration and gate oxide thickness.
基金supported by the National Natural Science Foundation of China(No.61274112)
文摘The impact of quantum confinement on the electrical characteristics of ultrathin-channel GeO1 n- MOSFETs is investigated on the basis of the density-gradient model in TCAD software. The effects of the channel thickness (Tch) and back-gate bias (Vbg) on the electrical characteristics of GeOI MOSFETs are examined, and the simulated results are compared with those using the conventional semi-classical model. It is shown that when T^h 〉 8 rim, the electron conduction path of the GeOI MOSFET is closer to the front-gate interface under the QC model than under the CL model, and vice versa when Tch 〈 8 rim. Thus the electrically controlled ability of the front gate of the devices is influenced by the quantum effect. In addition, the quantum-mechanical mechanism will enhance the drain-induced barrier lowering effect, increase the threshold voltage and decrease the on-state current; for a short channel length (≤ 30 nm), when Tch 〉 8 nm (or 〈 8 nm), the quantum-mechanical mechanism mainly impacts the subthreshold slope (or the threshold voltage). Due to the quantum-size effect, the off-state current can be suppressed as the channel thickness decreases.