Evaluation of VTH and RON Drifts during Switch-Mode Operation in Packaged SiC MOSFETs

Abstract

In this paper, we investigate the evolution of threshold voltage (VTH) and on-resistance (RON) drifts in the silicon carbide (SiC) power metal-oxide-semiconductor field-effect transistors (MOSFETs) during the switch-mode operation. A novel measurement setup for performing the required on-the-fly characterization is presented and the experimental results, obtained on commercially available TO-247 packaged SiC devices, are reported. Measurements were performed for 1000 s, during which negative VTH shifts (i.e., VTH decrease) and negative RON drifts (i.e., RON decrease) were observed. To better understand the origin of these parameter drifts and their possible correlation, measurements were performed for different (i) gate-driving voltage (VGH) and (ii) off-state drain voltage (VPH). We found that VTH reduction leads to a current increase, thus yielding RON to decrease. This correlation was explained by the RON dependence on the overdrive voltage (VGS–VTH). We also found that gate-related effects dominate the parameter drifts at low VPH with no observable recovery, due to the repeated switching of the gate signal required for the parameter monitoring. Conversely, the drain-induced instabilities caused by high VPH are completely recoverable within 1000 s from the VPH removal. These results show that the measurement setup is able to discern the gate/drain contributions, clarifying the origin of the observed VTH and RON drifts.

Experimental and numerical investigation of Poole–Frenkel effect on dynamic R ON transients in C-doped p-GaN HEMTs

“…Dynamic R ON transients were acquired by means of an inhouse characterization setup, presented in [12]. OFF-state stress (i.e., V GS,STR = 0 V < V T , and high V DS,STR ) was carried out up to 1000 s of cumulative stress time (t STR ) by either varying V DS,STR in the range 25-125 V (at fixed temperature, T = 30 • C), or varying T in the range 30 • C-110 • C (at fixed V DS,STR = 50 V).…”

Parameter extraction and selection for a scalable N-type SiC MOSFETs model and characteristic verification along with conventional dc-dc buck converter integration

“…These methods were very simple, were limited to few applications and offered a limited range of valid parameters and were limited to selective users. In [24], Marcello Ciono and et al contributed to gate driving voltage by stating R DSON dependence on (V GS −V TH ) and later on it became a reason for casing parameter drift.…”

Design and Comparative Analysis of an Ultra-Highly Efficient, Compact Half-Bridge LLC Resonant GaN Converter for Low-Power Applications

“…In comparison to Si MOSFET, they also demand less drive power, which lowers drive losses. Higher-frequency operation enables highly efficient and more compact converters by lowering the size of resonant converter passive components, or in other words, by minimizing the size of magnetics [10]. Devices made of GaN also have a very small on-resistance for a specific breakdown voltage than Si devices.…”