Sub-millisecond thermal impedance and steady state thermal resistance explored [power MOSFETs]

Thermal characterization of semiconductor devices has been ongoing in laboratories for the last forty years and techniques are well known. However, given the dated equipment that many manufacturers use, it is debatable whether these techniques are accurate. This paper (1) explores thermal impedance and thermal resistance measurement methods for power MOSFETs; (2) investigates test system measurement errors and a new test circuit for evaluation of transient pulse widths of 1 ms and narrower; (3) shows that not all characterization heat sinks are created equal.