We present a two-dimensional (2-D) analytical modeling of the surface potential of a double-gate vertical t-shaped tunnel field-effect transistor (TFET), considering the inherit dual modulation effect in such devices. This effect explains the control of the surface potential by both bias voltages, which are used to calculate the tunneling depletion width at the source and drain junctions. A model of the tunneling current in the device is derived based on the surface-potential model. The parabolic approximation is used to solve the 2-D Poisson equation with appropriate boundary conditions. The dependence of the surface potential profile on different parameters is analyzed by varying the gate–source potential, drain–source potential, gate oxide dielectric constant, gate metal work function, and different materials used. Finally, expressions for the surface potential of the channel along with the tunneling current are obtained, accurately capturing their variation with the gate and drain biases. The proposed method is verified by the agreement between its analytical results and technology computer-aided design (TCAD) simulation results.

中文翻译：

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双栅垂直T形隧道场效应晶体管的表面电势和漏极电流的二维分析建模

考虑到此类器件中的继承双重调制效应，我们提出了双栅极垂直T形隧道场效应晶体管（TFET）的表面电势的二维（2-D）分析模型。该效应说明了通过两个偏置电压对表面电势的控制，这两个偏置电压用于计算源极和漏极结处的隧穿耗尽宽度。基于表面电势模型，得出器件中的隧道电流模型。抛物线近似用于求解具有适当边界条件的二维泊松方程。通过改变栅极-源极电位，漏极-源极电位，栅极氧化物介电常数，栅极金属功函数和使用的不同材料，分析了表面电势轮廓对不同参数的依赖性。最后，获得了沟道表面电势与隧穿电流的表达式，准确地捕捉了它们在栅极和漏极偏置下的变化。该方法的分析结果与技术计算机辅助设计（TCAD）仿真结果之间的一致性验证了该方法的有效性。