A Closed-Form Model for N-Polar Gallium Nitride Heterostructures

The closed form model to calculate the charge density and surface potential in an N-polar GaN/AlGaN heterostructure is presented. The proposed model is developed from the solution of Schrodinger’s equation for a finite triangular potential well. The results from our model are validated with numerical data for a wide range of bias conditions, channel layer thickness and spacer layer mole fraction. Finally, the gate capacitance of the heterostructure is evaluated using automatic differentiation and validated against experimental data. This model will be useful in the development of closed-form current-voltage models for circuit level analysis involving N-polar MIS-HEMTs.

本文提出了一种用于计算N极性氮化镓/铝氮化镓（N-polar GaN/AlGaN）异质结构中电荷密度与表面电势的闭合形式模型。所提出的模型基于有限三角势阱的薛定谔（Schrödinger）方程求解推导而来。本模型的计算结果通过覆盖宽泛偏置条件、沟道层厚度以及间隔层组分摩尔分数的数值数据完成了验证。最后，本文采用自动微分法对该异质结构的栅电容进行了计算，并通过实验数据进行了验证。该模型将有助于开发适用于涉及N极性金属-绝缘体-半导体高电子迁移率晶体管（N-polar MIS-HEMTs）的电路级分析的闭合形式电流-电压模型。