Experimental determination of on and off state small-signal equivalent circuit of δ-doped PHEMTs

Abstract

A simple and accurate method for extracting on and off state equivalent circuit for double heterojunction δ-doped PHEMTs was developed, which is quite useful for switching applications. The circuit elements are extracted from the S-parameters of PHEMTs. Parasitic inductances Lg, Ld and Ls were determined from the on-wafer-short 8-parameter data. We have observed skin effect on the series resistive elements of on-wafer-short, which has been given due consideration in our model. The model has been verified by comparing the measured S-parameter data against those calculated from the on and off state equivalent circuits of PHEMTs.