大栅宽功率器件的分布性研究

Research on Distribution of Power FETs with Large Gate Width

随着器件工作频率的升高,以集总元件模型描述大栅宽功率器件引入的误差将越来越大,且这一趋势随着栅长的减小更加显著。对微波大栅宽功率器件的分布性作了初步研究,对传统建模和器件优化方法进行改进,将器件中的有源部分和无源部分分离开,利用微波传输线理论和奇偶模分析对器件的无源部分建模,在满足集总条件时对有源区建模,将两者综合建立了分段的线性模型。与测量结果进行了比较,表明分段模型取得了更为精确的结果;在此基础上又建立了分段的非线性模型,模拟和验证了大栅宽器件的早期非线性现象;最后还提出了功率器件栅宽优化设计的估算方法。

The model error becomes large when the power device with large gate width is described by a lumped component model with higher working frequency,and the trend is more remarkable with the decrease of gate length.The distribution effect of power FETs with large gate width was primary investigated.Compared to traditional modeling method,the device modeling was improved based on the theory of the transmission line and even-odd mode analysis.A linear segment-device model was built.The result is more accurate than that of the traditional model.Meanwhile a nonlinear segment-device model was provided for simulating the early nonlinear phenomena in the large gate width device.Finally,a way of evaluating the optimal gate width was proposed.