Parameter extraction procedure for high power SiC JFET

A practical parameter extraction procedure for power junction field effect transistor (JFET) is presented. The carrier mobility and carrier concentrations are very important parameters, strongly affecting the current capability and dynamic characteristics of the device for a given design. When modeling JFETs, values of these parameters usually are based on assumptions and given by a vendor in a range. As a result, model accuracy is compromised. In this paper, a step-by-step parameter extraction procedure is described that includes extraction of the mobility and the carrier concentration in the channel and drift regions based on knowledge of the device geometrical parameters. For the first time, carrier mobility in channel and drift regions of power JFET are extracted individually. It is found that channel and drift region mobilities can be very different for a given device, since they are strongly fabrication-process dependent. The developed procedure includes extraction of parameters for proposed empirical temperature dependencies of mobilities in the channel and drift regions. A simple static I-V characterization and C-V measurements are the only measurements required for the parameter extraction.