Lateral bipolar type input/output protection device
AssigneeNEC Corporation
InventorYasuyuki Morishita
Life of this patent
Estimating the term…
Abstract
A lateral bipolar type input/output protection device of the present invention includes a N type well formed below an emitter impurity diffusion layer of N type over a P type substrate. With such construction of the lateral bipolar type input/output protection device, a parasitic bipolar operation occurs easily and sufficient electrostatic durability without degradation of protection performance of the protection device even when a semiconductor integrated circuit is miniaturized by employing the STI isolation structure.
Claims13
A semiconductor device comprising:
- a semiconductor substrate of a first conductivity type;
- a first well of said first conductivity type formed on said semiconductor substrate;
- a second well of said first conductivity type formed on said semiconductor substrate;
- a third well of a second conductivity type formed on said semiconductor substrate between said first and second wells;
- a first diffusion layer of said first conductivity type formed on said first well;
- a second diffusion layer of said second conductivity type formed on said second well;
- a third diffusion layer of said second conductivity type formed on said third well;
- and
- an isolation region formed over said semiconductor substrate to isolate said first, second and third diffusion layers from each other.
A semiconductor device including a lateral bipolar type input/output protection device, said lateral bipolar type input/output protection device comprising:
- an emitter impurity diffusion layer of a first conductivity type;
- a well of said first conductivity type formed below said first emitter impurity diffusion layer;
- and
- an input/output terminal and an internal circuit connected to said input/output terminal to perform at least one of a first operation of receiving a signal from said input/output terminal and a second operation of transferring a signal to said input/output terminal, said lateral bipolar type input/output protection device being connected to said input/output terminal to protect said internal circuit from an electrostatic discharge.
Dependencies are inferred from the claim text.