New generation 6.5 kV SiC power MOSFET

Abstract

Following the recent advances in the production of 3.3 kV and 10 kV SiC power MOSFETs, Wolfspeed launched an effort to develop a new generation 6.5 kV SiC power MOSFET to fill the medium-to high-voltage fast switching device void in applications such as rail traction and medium-voltage motor drives. The characteristics of the new generation 6.5 kV SiC power MOSFET rated at a drain current of 30 A, are presented for the first time. The device shows a typical R <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">DS, on</sub> <; 90 mΩ and V <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">th</sub> of 3.6 V (at I <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">D</sub> =1 mA) measured at room temperature. Our 6.5 kV SiC power MOSFET includes a useable body diode with low V <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">f</sub> and reverse-recovery charge at operating temperature. The use of the body diode as a freewheeling device is demonstrated, eliminating the need for an external anti-parallel freewheeling SiC JBS diode, hence, reducing size and cost of a system. The effects of changing the 6.5 kV SiC power MOSFET gate runner design on the internal on-chip gate resistance and the MOSFET switching capability are presented.