A 2-D Semi-Analytical Model of Double-Gate Tunnel Field-Effect Transistor Xu Huifang (许会芳), Dai Yuehua*(代月花), Li Ning(李宁), Xu JianBin(徐建斌)

文中提出了一种双栅隧穿场效应晶体管(DG TFET)的二维半解析模型。通过在栅绝缘层和沟道区引入两个矩形源，运用半解析法和特征函数展开法求解二维泊松方程，得到电势的二维半解析解。解的结果是一个特殊函数，为无穷级数表达式。基于电势模型，求出最短隧穿长度( )和平均电场( )，运用Kane模型得到漏极电流。新模型考虑了移动电荷对电势的影响以及漏源电压对隧穿参数 和 的影响。文中计算了不同漏源电压，不同硅膜厚度，栅介质层厚度和栅介质层常数下的表面势和漏极电流。结果表明，新模型与仿真结果吻合。这将有助于DG TFET的优化设计，同时，也加深了DG TFET器件对电路结构设计的规划。

A 2-D semi-analytical model of double-gate tunnel field-effect transistor

A 2-D semi-analytical model of double gate (DG) tunneling field-effect transistor (TFET) is proposed. By aid of introducing two rectangular sources located in the gate dielectric layer and the channel, the 2-D Poisson equation is solved by using a semi-analytical method combined with an eigenfunction expansion method. The expression of the surface potential is obtained, which is a special function for the infinite series expressions. The influence of the mobile charges on the potential profile is taken into account in the proposed model. On the basis of the potential profile, the shortest tunneling length and the average electrical field can be derived, and the drain current is then constructed by using Kane's model. In particular, the changes of the tunneling parameters A_k and B_k influenced by the drain-source voltage are also incorporated in the predicted model. The proposed model shows a good agreement with TCAD simulation results under different drain-source voltages, silicon film thicknesses, gate dielectric layer thicknesses, and gate dielectric layer constants. Therefore, it is useful to optimize the DG TFET and this provides a physical insight for circuit level design.