A Novel Dual-Direction SCR Embedded With Segmental and Cross-Bridge Topology for High-Voltage ESD Protection

A novel dual-direction silicon-controlled rectifier (DDSCR) embedded with segmental and cross-bridge topology, which is named DDSCRESCT, is proposed and optimized for electrostatic discharge (ESD) protection. By segmenting N+ bridges and inserting a P+ bridge in DDSCR, the trigger voltage of the DDSCRESCT decreases to 10.3 V, which is attributed to the multiple avalanche breakdown effects. By embedding a floating N-type well in DDSCR, the holding voltage of the DDSCRESCT increases to 7.8 V, due to the low current gain of the parasitic bipolar junction transistors. Compared to DDSCR, the leakage current of the DDSCRESCT decreases about one order of magnitude and achieves a large failure current (I-t2) of 3.6 A, resulting from the segmental and cross-bridge topology design. By optimizing the length of the N+ segmental topology and the width of the P+ implanted bridge across the P-type well, the DDSCRESCT exhibits a good clamping ability and a decreased turn-on resistance of 2.1 ohm, resulting in a further similar to 16.2% increase of I-t2. The human body model (HBM) test of the DDSCRESCT with a finger width of 100 mu m can reach 4 kV due to the optimized segmental and cross-bridge topology design, which also offers great potential in providing high-voltage ESD protection.