Abstract3‐kV, 600‐A, 4H‐SiC flat package type pn diodes have been developed and their reverse recovery characteristics have been investigated. In spite of being pn junction diodes, the developed diodes have a short reverse recovery time of 0.153µs at room temperature. These diodes have one‐tenth lower recovery loss and one‐third lower recovery time than those of a commercialized 2.5‐kV Si diode in spite of a high blocking voltage. When this diode is used in a PWM inverter, the carrier frequency at which the on‐state loss is equal to the switching loss is 1.45 times the Si diode's frequency at 398 K. By using the developed diode, high‐voltage high‐frequency inverter operation can be realized. © 2007 Wiley Periodicals, Inc. Electr Eng Jpn, 160(1): 10–17, 2007; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/eej.20557