ELECTROSTATIC PROTECTIVE ELEMENT, ELECTROSTATIC PROTECTIVE CIRCUIT, AND SEMICONDUCTOR DEVICE

摘要

PROBLEM TO BE SOLVED: To efficiently reduce the triggering voltage of an electrostatic protective element using a simple configuration. SOLUTION: A MOS element is used mainly as a triggering element, and a charge generated by static electricity is injected to a base electrode B of a parasitic bipolar transistor 11 by at tunnel current Im of the MOS element as a support, thus rapidly increasing the base potential of the parasitic bipolar transistor 11. Also, to surely inject a tunnel current Im to the base electrode B of the parasitic bipolar transistor 11, a low-resistance layer is provided in a semiconductor substrate, and the alignment of the parasitic bipolar transistor 11 and the trigger element are devised.