SCS110AGC

Innovations Embedded Silicon Carbide Schottky Barrier Diodes White Paper ROHM MarketingUSA Presented by ROHM Semiconductor Silicon Carbide Schottky Barrier Diodes Taking Efficiency to the Next Level for PFC and Other Applications Introduction Schottky barrier diodes (SBDs) have been available for more than a decade but were not commercially viable The semiconductor industry has a well-established until recently. As a pioneer in SiC technology, ROHM history of “smaller, faster, and cheaper.” Improving Semiconductor expects that volume production will lead performance and reducing device cost while shrinking to SiC’s acceptance in more and more applications. packaging size is fundamental to virtually every semiconductor product type. For power products, improved performance is measured by increased efficiency and The Advantages of Silicon Carbide power density, higher power handling capability, and The highest performance silicon power diodes are wider operating temperature range. Such improvements Schottky barrier diodes. Not only do SBDs have the depend largely on the desirable characteristics of power lowest reverse recovery time (trr) compared to the components used, such as low switching and conduc- various types of fast recovery (fast recovery epitaxial), tion losses, high switching frequency, stable electrical ultrafast recovery and super-fast recovery diodes, they characteristics over a wide temperature range, high also have the lowest forward voltage drop (VF). Both of operating temperature, and high blocking voltage. As these parameters are essential to high efficiency. Table silicon power components approach their theoretical 1 shows a comparison of breakdown voltage, VF, and limits, compound semiconductor materials, such as sili- trr for commonly available diodes. While Schottky bar- con carbide (SiC) and gallium nitride (GaN), provide the rier diodes have the advantage of low forward losses capability to dramatically improve these parameters. and negligible switching losses compared to other diode Today, the need for higher efficiency in end products is more critical than ever. Although silicon power products technologies, the narrow bandgap of silicon limits their use to a maximum voltage of around 200 V. Si diodes continue to see incremental improvements, devices that operate above 200 V have higher VF and trr. based on compound semiconductor materials deliver Silicon carbide is a compound semiconductor with significantly better performance — in a large number of superior power characteristics to silicon, including a cases not possible with their silicon counterparts. This is bandgap approximately three times greater, a dielectric certainly true for the most basic components in power breakdown field 10 times higher and a thermal coef- electronics: diodes and transistors. Silicon carbide (SiC) ficient three times larger. These characteristics make it Type VBR (VRRM) VF (1) trr (1) Si Schottky Barrier Diode 15 V-200 V 0.3V-0.8 V