Full characterization of microwave low noise HEMTs: measurements vs. modeling

The up to date version working up to 40 GHz of a noise figure measuring system for the characterization of transistors in terms of noise, gain and scattering parameters through noise figure measurements only is presented. In the fully automated version the method is rapid and very accurate but it is so difficult to assemble and handle that a very skilled operator is needed. This can be accepted in a research laboratory but is a very hard task for manufacturers to test their products. So, we have recently set-up a "simplified" method which is easier to run and accurate enough for industrial applications. The method is based on the extraction of a noise model of the transistor from measurements of [S] through an automatic network analyzer and of one noise figure only.