The Characterisation and Large-Signal Modelling of InGaAs Pseudomorphic High Electron Mobility Transistors

A high-performance pseudomorphic InGaAs/AIGaAs HEMT has been characterised from DC to microwave frequencies, using a powerful measurement-based parameter extraction methodology. This methodology has alreadt beea proved to work for conventional FET "on-wafer" structures [7] and uses DC and broad-band multi-bias point (CW) S-parameter measurements to determine all the elements of the equivalent circuit. This technique hast bees now developed to include a simple but efficient optimisation strategy, for extracting package-related parasitics. Accurate non-linear models for the gate capacitances and the drain-circuit elements are proposed, leading to an effective large-signal universal model for P-HEMT devices. The model is validated by comparing DC, small and large-signal experimental results with simulations performed with the HP-MDS simulator.