AC-Stress Degradation in SiC MOSFETs

Thermal instability effects in SiC Power MOSFETs

Silicon carbide (SiC) power MOSFETs are characterised by potentially thermally unstable behaviour over a broad range of bias conditions. In the past, such behaviour has been shown for silicon (Si) MOSFETs to be related to a reduction of Safe Operating Area at higher drain–source bias voltages. For SiC MOSFETs no characterisation exists yet. This paper presents a thorough experimental investigat...

Technology for Controlling Trench Shape in SiC Power MOSFETs

As the worldwide consumption of energy is increases and the global environment steadily deteriorates, society must find more efficient ways to utilize energy in order to achieve sustainable advances. Accordingly, the field of power electronics is of vital importance, and huge advances in power semiconductor devices are anticipated. Power semiconductor devices that use silicon (Si) are said to b...

Threshold voltage instabilities of present SiC-power MOSFETs under positive bias temperature stress

We study the threshold voltage (Vth) instability of commercially available silicon carbide (SiC) power MOSFETs or prototypes from four different manufacturers under positive bias temperature stress (PBTS). A positive bias near Vth causes a threshold voltage shift of 0.7 mV per decade in time per nanometer oxide thickness in the temperature range between -50°C and 150°C. Recovery at +5 V after a...

Single pulse avalanche robustness and repetitive stress ageing of SiC power MOSFETs

This paper presents an extensive electro-thermal characterisation of latest generation Silicon Carbide (SiC) power MOSFETs under Unclamped Inductive Switching (UIS) conditions. Tests are carried out to thoroughly understand the single pulse avalanche ruggedness limits of commercial SiC MOSFETs and assess their ageing under repetitive stress conditions. Both a functional and a structural charact...

Threshold-voltage bias-temperature instability in commercially-available SiC MOSFETs