A simplification method for capacitance models in AlGaN/ GaN high electron mobility transistors under large drain voltage using channel analysis

摘要

This article analyzes the bias dependence of gate-drain capacitance (C_(gd)) andgate-source capacitance (C_(gs)) in the AlGaN/GaN high electron mobility transistorsunder a high drain-to-source voltage (V_(ds)) from the perspective of channelshape variation, and further simplifies C_(gd) and C_(gs) to be gate-to-sourcevoltage (V_(gs)) dependent only at high Vds. This method can significantly reducethe number of parameters to be fitted in C_(gd) and C_(gs) and therefore lower thedifficulty of model development. The Angelov capacitance models are chosenfor verifying the effectiveness of simplification. Good agreement between simulatedand measured small-signal S-parameters, large-signal power sweep, andpower contours comprehensively proves the accuracy of this simplificationmethod.