A direct extraction method to determine the small-signal equivalent circuit model for III–V compound heterojunction bipolar transistor device is proposed in this paper. The advantage of this method is that the extrinsic resistances can be determined directly from a cut-off S-parameters measurement at the millimetre-wave frequencies (30–110 GHz) based on the T-π transformation method. After de-embedding the extrinsic elements, all intrinsic elements of the π-type model can be obtained utilizing a set of closed-form expressions. Good agreement between modeled and measured data is achieved up to 110 GHz to verify the accuracy.

中文翻译：

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基于高达110GHz的S参数测量来直接确定InP HBT器件的外部电阻的直接提取方法

本文提出了一种直接提取方法来确定III-V族化合物异质结双极晶体管器件的小信号等效电路模型。这种方法的优势在于，可以根据T-π转换方法，通过在毫米波频率（30–110 GHz）上的截止S参数测量直接确定外部电阻。取消嵌入非本征元素后，可以使用一组封闭形式的表达式获得π型模型的所有本征元素。在高达110 GHz的频率下，建模数据和测量数据之间达到了良好的一致性，从而验证了准确性。