3rd generation Silicon Carbide(SiC) MOSFETs

Toshiba's 3rd generation Silicon Carbide (SiC) MOSFETs introduces a selection of both 650V and 1200V voltage products. In common with 2nd generations, Toshiba's newest generation of MOSFETs include a built-in SiC Schottky Barrier Diode (SBD) with a low forward voltage (VF) of -1.35V (typ.), placed in parallel with the PN diode in the SiC MOSFETs, to suppress fluctuation in RDS(on) thereby enhancing reliability. Furthermore, Toshiba’s advanced SiC process[1] has greatly improved our on-resistance per unit area RonA, and the performance index Ron*Qgd, which indicates switching characteristics, compared to 2nd generation products. Also, it has easy to design gate drive circuit, and you can prevent malfunctions due to switching noise.
Toshiba's 3rd generation SiC MOSFETs provides lower power consumption and supports higher power density for applications such as switching power supplies (servers for data centers, communication equipment, etc.), uninterruptible power supplies (UPS), PV inverters, EV charging stations, etc.

Features of the 3rd Generation SiC MOSFETs

1. Built-in SBD achieves low VF and high reliability(Following the 2nd generation)

Toshiba developed a structure in which a Schottky barrier diode (SBD) is built in parallel with the PN diode of the SiC MOSFETs. It has low VF characteristics and greatly suppresses Ron fluctuation due to defect expansion in the SiC crystal[2].

Comparison of on-resistance fluctuations between the SiC MOSFETs without built in SBD and the SiC MOSFETs with built in SBD.

2. Significantly improved on-resistance and switching loss

By utlizing Toshiba's advanced device structure, the on-resistance per unit area RonA has been reduced by 43%[3] compared to the second generation product, and the performance index Ron*Qgd, which indicates switching losses, has been reduced by 80%[4].

Comparison of R<sub>on</sub>A between the new 1.2kV SiC MOSFETs and the latest generation of SiC MOSFETs of other companies when R<sub>on</sub>A of its second-generation SiC MOSFETs is taken as 1.
Comparison of R<sub>on</sub>*Q<sub>gd</sub> between the new 1.2kV SiC MOSFETs and the latest generation of SiC MOSFETs of other companies when R<sub>on</sub>*Q<sub>gd</sub> of its second-generation SiC MOSFETs is taken as 1.

The turn-on and turn-off waveforms of the 2nd and 3rd generation SiC MOSFETs under the following measurement conditions are shown below.
Measurement Conditions :VDD=800V, ID=20A, L=100μH, RG(external gate resistor)=4.7Ω

Turn-on waveforms of 1.2-kV class secondand third-generation SiC MOSFETs.
Turn-On waveform
Turn-off waveforms of 1.2-kV class secondand third-generation SiC MOSFETs.
Turn-Off waveform

3. High noise resistance and easy to use

The wide gate-source voltage range (VGSS: -10V(min) to 25V(max)) and high gate threshold voltage (Vth: 3V(min) to 5V(max)) facilitate gate drive circuit design and prevent malfunctions due to switching noise.

Comparion of gate-source voltage (V<sub>GSS</sub>) and gate threshold voltage (V<sub>th</sub>) with other companies' products.

(1200V voltage product, as of August 2022, Toshiba research)

 

[1] As of August 2022

[2] Toshiba defines reliability as a change in on-resistance when a current is applied from the source to the drain of a device at a current density of 250 A/cm2 for 1,000 hours. On-resistance changes by as much as 43% for Toshiba’s typical MOSFET, but it changes by only 3% in an SBD-embedded MOSFET.

[3] Comparison of the 1.2kV 3rd generation SiC MOSFETs when RonA is set to 1 in the 2nd generation SiC MOSFETs. (Toshiba test results)

[4] Comparison of the 1.2kV 3rd generation SiC MOSFETs when Ron*Qgd is set to 1 in the 2nd generation SiC MOSFETs is set to 1. (Toshiba test results)