Renesas Electronics Corporation

Kouichi Sawahata

Masaharu Sato

In an aspect of the present invention, an ESD (Electrostatic Discharge) protection element includes a bipolar transistor comprising a collector diffusion layer connected with a first terminal and an emitter diffusion layer; and current control resistances provided for a plurality of current paths from a second terminal to the collector diffusion layer through the emitter diffusion layer, respectively. The bipolar transistor further includes a base diffusion region connected with the second terminal through a first resistance which is different from the current control resistances.

ESD protection element

An electrostatic discharge (ESD) protection element using an NPN bipolar transistor, includes: a trigger element connected at one end with a pad. The NPN bipolar transistor includes: a first base diffusion layer; a collector diffusion layer connected with the pad; a trigger tap formed on the first base diffusion layer and connected with the other end of the trigger element through a first wiring; and an emitter diffusion layer and a second base diffusion layer formed on the first base diffusion layer and connected in common to a power supply through a second wiring which is different from the first wiring.

A first first-conductivity-type diffusion layer, a first second-conductivity-type diffusion layer, a second first-conductivity-type diffusion layer, and a second second-conductivity-type diffusion layer are arranged in this order. In a region where the second second-conductivity-type diffusion layer and the first-conductivity-type layer are in contact with each other, impurity concentrations thereof are higher in a part in contact with a side face of the second second-conductivity-type diffusion layer than in a part at a bottom surface of the second second-conductivity-type diffusion layer.

Semiconductor device

A protection circuit according to an embodiment of the present invention is provided between a first terminal and a second terminal and includes: a capacitor element having one end connected to the second terminal; and a multi-cathode thyristor formed on a semiconductor substrate, and including an anode connected to the first terminal, a first cathode connected to the second terminal, and a second cathode disposed between the anode and the first cathode and connected to another terminal of the capacitor element.

Growing community of inventors

Kanagawa, Japan

Kouichi Sawahata