Design of 4H-SiC-Based Silicon-Controlled Rectifier With High Holding Voltage Using Segment Topology for High-Voltage ESD Protection

In this letter, a new silicon-controlled rectifier (SCR) structure fabricated using 4H-SiC materials has been proposed and investigated. The proposed structure alleviates the strong-snapback phenomenon that occurs in the 4H-SiC SCR and demonstrates low trigger voltage and high holding voltage characteristics. The proposed device exhibits improved snapback characteristics with very high holding voltage against electrostatic discharge surges owing to the structural features and application of segment topology. It also has excellent on-resistance and improved thermal reliability owing to the physical characteristics of 4H-SiC. Traditional SCR and low-voltage trigger SCR (LVTSCR) are fabricated with 4H-SiC under the same conditions and their electrical characteristics are comparatively analyzed with those of the proposed SCR. This study also evaluates the electrical characteristics at high temperatures (300–500 K) to verify the high- temperature reliability of the proposed structure.