一种非均匀掺杂的全耗尽SOI-MOSFET阈值电压模型

对垂直于沟道的二维电势分布函数提出了一种新的近似,给出了基于这种近似的杂质浓度呈高斯分布的非均匀掺杂全耗尽SOI-MOSFET的阈值电压解析模型.模型结果与MEDICI数值模拟结果符合得很好,表明了模型的准确性,这为实践中分析与控制非均匀掺杂的全耗尽SOI-MOSFET的阈值电压提供了一种新的途径.     

一种非均匀掺杂的全耗尽SOI-MOSFET阈值电压模型

对垂直于沟道的二维电势分布函数提出了一种新的近似,给出了基于这种近似的杂质浓度呈高斯分布的非均匀掺杂全耗尽SOI-MOSFET的阈值电压解析模型.模型结果与MEDICI数值模拟结果符合得很好,表明了模型的准确性,这为实践中分析与控制非均匀掺杂的全耗尽SOI-MOSFET的阈值电压提供了一种新的途径.     

适用于VLSI CAD的非均匀掺杂小尺寸MOSFET阈值电压模型

本文讨论了目前使用的MOSFET阈值电压模型的局限性,尝试了用分段近似法求解非均匀掺杂MOSFET的阈值电压,在此基础上提出了一个新的模型公式.它能反映非均匀掺杂MOSFET 阈值电压衬偏特性;不仅适用于浅注入,而且适用于深注入情况;不仅适用于长沟道,而且适用于小尺寸器件.此模型的计算结果同数值分析器MINIMOS的有关计算值相比,符合得很好.该模型公式特别适用于 VLSI CAD.     

An Analytical Threshold Voltage Model for Fully Depleted SOI MOSFETs

提出了一种新的全耗尽SOI MOSFETs阈值电压二维解析模型.通过求解二维泊松方程得到器件有源层的二维电势分布函数,氧化层-硅界面处的电势最小值用于监测SOI MOSFETs的阈值电压.通过对不同栅长、栅氧厚度、硅膜厚度和沟道掺杂浓度的SOI MOSFETs的MEDICI模拟结果的比较,验证了该模型,并取得了很好的一致性.     

全耗尽SOI MOSFETs阈值电压解析模型

提出了一种新的全耗尽SOI MOSFETs阈值电压二维解析模型.通过求解二维泊松方程得到器件有源层的二维电势分布函数,氧化层-硅界面处的电势最小值用于监测SOI MOSFETs的阈值电压.通过对不同栅长、栅氧厚度、硅膜厚度和沟道掺杂浓度的SOI MOSFETs的MEDICI模拟结果的比较,验证了该模型,并取得了很好的一致性.     

全耗尽SOI MOSFETs阈值电压和电势分布的温度模型

提出了一个全耗尽SOI MOSFETs器件阈值电压和电势分布的温度模型.基于近似的抛物线电势分布模型,利用适当的边界条件对二维的泊松方程进行求解.同时利用阈值电压的定义得到了阈值电压的模型.该温度模型详细地研究了电势分布和阈值电压跟温度之间的变化关系,同时还近似地探讨了短沟道效应.为了进一步验证模型的正确性,利用SILVACO ATAS软件进行了相应的模拟.结果表明,模型计算与软件模拟吻合较好.     

全耗尽SOI MOSFETs阈值电压和电势分布的温度模型

提出了一个全耗尽SOI MOSFETs器件阈值电压和电势分布的温度模型. 基于近似的抛物线电势分布模型,利用适当的边界条件对二维的泊松方程进行求解. 同时利用阈值电压的定义得到了阈值电压的模型. 该温度模型详细地研究了电势分布和阈值电压跟温度之间的变化关系,同时还近似地探讨了短沟道效应. 为了进一步验证模型的正确性,利用SILVACO ATAS软件进行了相应的模拟. 结果表明,模型计算与软件模拟吻合较好.     

非对称HALO结构的全耗尽SOI二维阈值电压解析模型

在考虑了隐埋层与硅层的二维效应的基础上提出非对称HALO结构的全耗尽SOI二维阈值电压解析模型,该模型计算了在不同硅膜厚度,掺杂浓度,HALO区占沟道比例的条件下的阈值电压.模型结果与二维数值模拟软件MEDICI的模拟结果较好的吻合,该模型对HALO结构的物理特性和工艺设计有很好的指导意义.     

全耗尽阶梯掺杂沟道围栅MOSFET二维解析模型

采用分离变量法求解柱坐标系下二维泊松方程,建立了考虑耗尽电荷和自由电荷的全耗尽阶梯掺杂沟道围栅MOSFET的二维体电势模型,并在此基础上得到阈值电压和亚阈值摆幅的解析模型。研究了不同区域长度和漏压下的表面势,分析了不同掺杂的区域长度和掺杂浓度对器件性能的影响。结果表明,与均匀掺杂的GAA MOSFET相比,阶梯掺杂结构不仅降低了漏端电场,而且能更好地抑制短沟道效应和热载流子效应;通过对掺杂区域参数进行优化,可以提高器件的可靠性。     

薄膜SOI MOS器件阈值电压的解析模型分析

研究了薄膜全耗尽增强型 SOIMOS器件阈值电压的解析模型 ,并采用计算机模拟 ,得出了硅膜掺杂浓度和厚度、正栅和背栅二氧化硅层厚度及温度对阈值电压影响的三维分布曲线 ,所得到的模拟结果和理论研究结果相吻合。     

Threshold Voltage Model of Short-Channel FD-SOI MOSFETs With Vertical Gaussian Profile

A novel approximation of 2-D potential function perpendicular to the channel for fully depleted (FD) silicon-on-insulator (SOI) MOSFETs on films with vertical Gaussian profile is proposed in the paper, then an analytical threshold voltage model is derived. The model agrees well with the MEDICI numerical simulation results. It represents a feasible way to find the threshold voltage and gives some reference points in developing new 2-D models for nonuniform FD-SOI devices.     

Temperature dependence of threshold voltage in thin-film SOIMOSFETs

A first-order model for the temperature dependence of threshold voltage in thin-film silicon-on-insulator (SOI) n-MOSFETs is described. The temperature dependence of the threshold voltage of thin-film SOI n-channel MOSFETs is analyzed. Threshold voltage variation with temperature is significantly smaller in thin-film (fully depleted) devices than in thick-film SOI and bulk devices. The threshold voltage is shown to be dependent on the depletion level of the device, i.e. whether it is fully depleted or not. There exists a critical temperature below which the device is fully depleted, and above which the device operates in the thick-film regime     

Modeling of Surrounding Gate MOSFETs With Bulk Trap States

We report a simple analytical model for surrounding gate MOSFETs including bulk traps. Based on the depletion approximation and the assumption that bulk traps are uniformly distributed inside the bandgap, we solved Poisson's equation in cylindrical coordinates and derived the general solution of potential distribution. Extraction of threshold voltage and subthreshold slope were conducted. The analytical solution yields good agreement with MEDICI simulations confirming the model. The model predicts a linear threshold voltage drop, depending on the trap density, as the diameter of the device decreases when the channel is fully depleted     

隐埋层中二维效应对全耗尽SOI非对称HALO结构阈值电压的影响

在非对称HALO结构的全耗尽SOI二维阈值电压解析模型的基础上,对阈值电压受隐埋层中二维效应的影响进行了讨论.通过与一维模型的比较,说明在深亚微米SOI MOSFET器件中隐埋层的二维效应会导致器件提前出现短沟道效应.新模型结果与二维数值模拟软件MEDICI吻合较好.     

A new 2-D model for the potential distribution and threshold voltage of fully depleted short-channel Si-SOI MESFETs

A new two-dimensional (2-D) analytical model for the threshold voltage of a fully depleted short-channel Si-MESFETs fabricated on the silicon-on-insulator (SOI) has been presented in this paper. The 2-D potential distribution functions in the active layer of the device is approximated as a parabolic function and the 2-D Poisson's equation has been solved with suitable boundary conditions to obtain the bottom potential at the Si/oxide layer interface. The calculations have been carried out for both uniform and nonuniform doping profiles in two dimensions. The minimum bottom potential is used to monitor the drain-induced barrier lowering effect and consequently an analytical expression for the threshold voltage of the device has been derived. The numerical results for the bottom potential and threshold voltage considering a wide range of device parameters have also been presented. The model has been compared with the simulated results obtained by using the ATLAS Device Simulation Software to show the validity of the proposed model. For uniform doping profile, the numerical results have also been compared with the reported data in the literature and a good agreement is observed among the three. The proposed model is simple and easy to understand the behavior of the fully depleted short-channel SOI-MESFETs as compared to the other models reported in the literature.     

考虑量子效应的双栅MOSFET的阈电压解析建模

推导了双栅MOSFET器件在深度方向上薛定谔方程的解析解以求得电子密度和阈电压.该解析解考虑了任意深度情况下沟道中深度方向上电势的不均匀分布,结果与数值模拟吻合.给出了电子密度的隐式表达式和阈电压的显式表达式,它们都充分考虑了量子力学效应.模型显示,在亚阈值区或者弱反型区,电子密度随深度增加而增加;然而,在强反型区,它与深度无关,这与数值模拟的结果吻合.结果进一步显示,只考虑方形势阱的量子力学结果,略高估计了阈电压,且低估了电子密度.误差随着深度的增加或者栅氧厚度的减少而增加.