A technique for extracting small-signal equivalent-circuit elements of HEMTs

We propose a new technique that is able to extract the small-signal equival ent-circuit elements of high electron mobility transistors (HEMTs) without causing any gate degradation. For the determination of extrinsic resistance values, unlike other conventional techniques, the proposed technique does not require an additional relationship for the resistances. For the extract ion of extrinsic inductance values, the technique uses the R-estimate, whic h is known to be more robust relative to the measurement errors than the co mmonly used least-squares regression. Additionally, we suggest an improved cold HEMT model that seems to be more general than conventional cold HEMT m odels. With the use of the improved cold HEMT model, the proposed technique extracts the extrinsic resistance and inductance values.