ESD protection device for enhancing reliability and for providing control of ESD trigger voltage

摘要

A diode-triggered NPN ESD protection device includes a P-Base region enclosing the emitter region of the NPN transistor for enhancing the reliability of the ESD protection device. The incorporation of the P-Base region encourages bulk transistor action and inhibits surface transistor action such that the reliability of the protection device is enhanced. In another aspect of the present invention, a trigger voltage control method is applied to a diode-triggered ESD protection device to extend the periphery length of the p-n junction of the trigger diode without increasing the size of the protection device. By extending the periphery length of the p-n junction, the trigger current generated by the trigger diode is increased so that the trigger voltage for the ESD protection device can be lowered, providing effective ESD protection. The periphery length is extended by using a shaped periphery, such as a corrugated periphery or a perforated periphery.