Lateral-diode, vertical-SCR hybrid structure for high-level ESD protection
Abstract:
A lateral p-n diode in the center of and surrounded by a vertical Silicon-Controlled Rectifier (SCR) forms an Electro-Static-Discharge (ESD) protection structure. The lateral p-n diode has a cross-shaped P+ diode tap with four rectangles of N+ diode regions in each corner of the cross. A P-well under the P+ diode tap is also an anode of a vertical PNPN SCR that has a deep N-well in a P-substrate. The deep N-well surrounds the lateral diode. Triggering MOS transistors are formed just beyond the four ends of the cross shaped P+ diode tap. Each triggering MOS transistor has N+ regions at the edge of the deep N-well and in the P-substrate that act as the cathode terminals. A deep P+ implant region under the N+ region at the edge of the deep N-well decreases a trigger voltage of the vertical SCR.
Information query
Patent Agency Ranking
0/0