Extraction of the series resistances and effective channel length of GaAs MESFETs by means of electrical methods: a numerical study

Abstract

This paper presents a numerical study on electrical methods to measure the source and drain resistances and the effective channel length of state of the art Gallium Arsenide MESFETs. In particular, the effects of scaling on the physical meaning and gate voltage dependence of the extracted values are investigated. Fringing effects at the gate edges are found responsible for a substantial bias dependence of the series resistances, hence for possible inaccuracies of extraction procedures that overlook such phenomena. A new extraction technique is also proposed to overcome in part the limitations of conventional approaches.