Traditional lumped small signal equivalent circuit models of AlGaN/GaN metal oxide semiconductor high electron mobility transistors (MOS-HEMTs) are made up of constant valued circuit elements. Such models are unable to capture the high frequency behavior (above 20 GHz) of the device. In this work, a modified small signal equivalent circuit model of AlGaN/GaN MOS-HEMTs is presented. The key feature of the proposed model is that the values of the different circuit elements in the model are considered to be frequency dependent in nature and not constants. The frequency dependent value of each circuit element is mathematically represented using polynomial functions where the coefficients of the functions are determined via a least-square curve fitting approach. This frequency dependent attribute of the circuit element values ensures that the proposed model is very accurate at high frequencies without sacrificing the compactness of the model topology. The accuracy of the proposed model has been verified up to 50 GHz using experimentally measured Y-parameters of AlGaN/GaN MOS-HEMTs having a different gate dielectric and gate length.

中文翻译：

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用于 AlGaN/GaN MOS-HEMT 高频分析的广义频率相关小信号模型


AlGaN/GaN 金属氧化物半导体高电子迁移率晶体管 (MOS-HEMT) 的传统集总小信号等效电路模型由恒定值电路元件组成。此类模型无法捕获设备的高频行为（20 GHz 以上）。在这项工作中，提出了一种改进的 AlGaN/GaN MOS-HEMT 的小信号等效电路模型。所提出模型的关键特征是模型中不同电路元件的值被认为本质上是频率相关的而不是常数。每个电路元件的频率相关值使用多项式函数进行数学表示，其中函数的系数通过最小二乘曲线拟合方法确定。电路元件值的这种频率相关属性确保所提出的模型在高频下非常准确，而不会牺牲模型拓扑的紧凑性。使用具有不同栅极电介质和栅极长度的 AlGaN/GaN MOS-HEMT 的实验测量 Y 参数，已在高达 50 GHz 的频率下验证了所提出模型的精度。