Development of SiC Superjunction MOSFET: A Review

Abstract

Silicon Carbide (SiC) is a booming semiconductor material with a wider bandgap than silicon, which brings superior electrical performance for applications such as high critical electric field, good high-temperature characteristics, etc. Among SiC devices, MOSFET received increasing attention, due to its excellent advantages such as low switching loss, high operating frequency, etc. In recent years, SiC MOSFETs were under fast development, while facing numerous challenges. For high voltage SiC MOSFET, the size of the device and drift region resistance are the main bottlenecks.The superjunction (SJ) structure is well-known as a "milestone" in the history of power devices, especially for MOSFET. Superjunction achieved a better trade-off between the breakdown voltage and the specific on-resistance by introducing a transverse electric field to the drift layer. A 3.3kV-class SiC SJ MOSFET was so far reported as a ultra-low specific on-resistance for 3.3 mΩcm2 at room temperature and 6.2 mΩcm2 at 175℃.[21] However, the development of SiC SJ MOSFETs is facing challenges, in terms of the fabrication of the p-pillar, the charge balance condition, etc. In this paper, recent progress on SiC SJ MOSFET was reviewed and listed through countries and regions. Achievements in both theoretical simulation and device fabrication were analyzed and compared. Moreover, constraints and prospects for the development of SiC SJ MOSFET were also discussed. Through this review, it is expected to help researchers to summarize recent advances on the SiC SJ MOSFET and to analyze the future trends, and to provide strategic planning for practitioners.