Cell-by-Cell SCR ESD Protection Structures in 28nm CMOS

Silicon-Controlled Rectifier (SCR) electrostatic discharge (ESD) protection structures are widely used due to the high ESD robustness and area efficiency. Yet, conventional SCR ESD layout is still a design issue. This paper reports a novel cell-by-cell type SCR ESD structure where the ESD device is formed across the four edges of SCR cells aiming for higher layout efficiency and ESD discharging uniformity. This new cell-by-cell SCR ESD structure is validated in foundry 28nm CMOS, showing good ESD protection performance in measurement.