AlGaN/GaN 高电子迁移率晶体管解析模型

基于电荷控制理论,考虑到极化效应和寄生漏源电阻的影响,建立了能精确模拟AlGaN/GaN高电子迁移率晶体管直流I-V特性和小信号参数的解析模型.计算表明,自发极化和压电极化的综合作用对器件特性影响尤为显著,2V栅压下,栅长为1μm的Al_0.2Ga_0.8N/GaN HEMT获得的最大漏电流为1370mA/mm;降低寄生源漏电阻可以获得更高的饱和电流、跨导和截至频率.模拟结果同已有的测试结果较为吻合,该模型具有物理概念明确且算法简单的优点,适于微波器件结构和电路设计.

Analytical Model for AlGaN/GaN High Electron Mobility Transistor

Based on the charge control theory,an accurate analytical model for the dc I-V characteristics and small signal parameters of an AlGaN/GaN high electron mobility transistor(HEMT) is developed considering the effects of polarization and parasitic source-drain resistances.Results show that the joint effects of spontaneous and piezoelectric polarization on the performance of the device are highly dominant.The proposed model predicts a maximum saturation current of 1370mA/mm at a gate bias of 2V for a 1.0μm Al_0.2Ga_0.8N/GaN HEMT.The calculated results also indicate that higher saturation current,transconductance,and cutoff frequency can be achieved by lowering the parasitic resistances.The comparison between simulations and physical measurements shows a good agreement.The model is simple in calculations and distinct in physical mechanism,therefore suitable for design and research of microwave device and circuit.