An improved C-V model of GaAs MESFETs for CAD of high speed circuits and broadband amplifiers

摘要

In this paper a semiempirical capacitanceudmodel of GaAs FET, very useful for CAD of MMIC, isudproposed. The model fits the results of two dimensionalud(2-D) simulations of device behaviour, accounting for theudmost important microwave effects, by means of theuddetermination of an effective shape of the depletionudregion in the active channel.udSimple physical equations and a few effective empiricaludparameters, with a precise physical meaning, areudemployed. So the initial estimation of parameters andudtheir extraction procedure result to be very easy.udIn spite of its semiempirical nature the model does notudleave the control over physical and technological deviceudparameters to circuit designer, necessary to achieve audreliable design.udThe model usefulness and accuracy are experimentallyudconfirmed to be very satisfactory for different kinds ofudMESFETs.