Dynamic Transfer Characteristics Measurement Method for SiC MOSFETs at Realistic Drain Voltages

Abstract

Transfer characteristics are essential for device modeling and circuit design in various applications. Transfer characteristics measurements for high voltage power devices are usually carried out in a curve tracer. Due to the limitation of the experimental setup, the pulse length is typically longer than $\mathbf{2 0 0} \boldsymbol{\mu} \mathbf{s}$ and must be applied repeatedly to determine the correct operating point. Both factors cause significant self-heating of the device under test (DUT), which distorts the measurement results. Currently transfer characteristics are measured with a low drain source voltage range (10 V to 20 V), that fails to capture the real application condition. In this paper, the dynamic transfer measurement for SiC MOSFETs is investigated in different operation conditions, which enables measurement of transfer characteristics at higher drain voltages. With the new proposed dynamic approach, the transconductance is measured at application related drain voltage, which provides more accurate information to designers for their simulation model and for circuit design. The dynamic transfer characteristic measurement could be done together with the dynamic gate charge measurement based on a doublepulse test, eliminating the need for additional characterization steps.