Extraction of state function behaviour from large signal waveform measurements [pHEMTs]

The nonlinear state functions of the pHEMT (pseudomorphic high electron mobility transistor) are fully extracted using dynamic measurements only. A systematic reverse waveform measurement technique combined with forward waveform measurements yield the intrinsic current and charge surface state functions. The reverse extraction results have been verified to be bias and power level independent and the resultant state functions obtained are confirmed to be unique. The technique shown is able to completely characterise state function behaviour and hence minimizes the extrapolation problems associated with existing state function extraction techniques.