Wide Bandgap Semiconductors for Power Electronics

12Unipolar Device in SiC: Diodes and MOSFETs

Sei‐Hyung Ryu

Wolfspeed, a Cree Company, Power Device R&D, 4600 Silicon Drive, Durham, NC 27703, USA

12.1 Introduction

Power devices in 4H‐silicon carbide (4H‐SiC) show great performance advantages as compared to those made with other semiconductors. Compared to silicon, 4H‐SiC has one order of magnitude higher breakdown electric field (2–4 × 10⁶ V/cm), while bulk electron mobility is only about 20% lower than that of silicon. The drift layer of a 4H‐SiC power device may have one‐tenth the thickness and one hundred times the doping concentration of the drift layer of a silicon power device with the same blocking capability, resulting in about a factor of 800 reduction in drift layer resistance ...