High speed non-linear device characterization and uniformity investigations at X-band frequencies exploiting behavioral models

This paper outlines a non-linear measurement approach suitable for wafer mapping and technology screening applications. It is shown how rapid characterization and uniformity investigations of non-linear devices is possible through the development of an intelligence driven, open-loop active harmonic load pull measurement system, where localized behavioral models are exploited to dramatically improve measurement system speed and to improve utilization efficiency. The load pull measurement results obtained were then used to extract 5th order behavioral models for robust CAD integration. Device variations can now be included within the CAD tool. Technique demonstration involved the measurements of 10×75 μm GaAs pHEMT devices, operating at 9 GHz, biased in Class-AB on four different wafers. An example CAD investigation comparing the variation of the measured and modeled current and voltage waveforms is discussed.