Patent ID: 6462601
Filing Date: 2002-10-08
Classification: G11C,H01L

Abstract:
An electrostatic discharge (ESD) protection circuit layout for an integrated circuit device, comprising:a first ESD protection device coupled to a first voltage source and a bonding pad; a second ESD protection device coupled to a first ground terminal and the bonding pad; a first charge-device model (CDM) ESD protection device coupled to a second voltage source and the bonding pad; a second CDM ESD protection device coupled to a second ground terminal and the bonding pad; a first charge flow prevention device coupled to the second voltage source; a PMOS transistor, wherein a source terminal of the PMOS transistor is connected to the first charge flow prevention device, and a substrate terminal and the source terminal of the PMOS transistor are connected together; an input resistor coupled to a gate terminal of the PMOS transistor and the bonding pad; an NMOS transistor, wherein a drain terminal of the NMOS transistor is connected to a drain terminal of the PMOS transistor, a gate terminal of the NMOS transistor is connected to the gate terminal of the PMOS transistor, and a substrate terminal and a source terminal of the NMOS transistor are connected together; a second charge flow prevention device coupled to the source terminal of the NMOS transistor and the second ground terminal; and substrate resistor coupled to the first ground terminal and the second ground terminal; wherein the first charge flow prevention device prevents any abnormal charge current from flowing from the second voltage source through a gate oxide layer of the PMOS transistor and damaging the PMOS transistor, the first CDM ESD protection device provides a discharging loop so that any abnormal charge current from the second voltage source is channeled to the bonding pad via the first CDM ESD protection device, similarly, the second charge flow prevention device prevents any abnormal charge current from flowing from the substrate of the integrated circuit device through a gate oxide layer of the NMOS transistor and damaging the NMOS transistor, the second CDM ESD protection device provides a discharging loop so that any abnormal charge current from the substrate of the integrated circuit device is channeled to the bonding pad via the second CDM ESD protection device, and the first CDM ESD protection device and the second CDM ESD protection device within the integrated circuit device are positioned far away from the NMOS and PMOS transistor so that electrical latch-up is minimized.