Patent ID: 6147852
Filing Date: 2000-11-14
Classification: H01L

Abstract:
An electrostatic discharge protection circuit for monolithic integration into an integrated circuit device with at least one input terminal and at least one output terminal. said protection circuit comprising:at least one transistor having a first terminal. a second terminal. and a control terminal. the first terminal of the transistor being connected to the input terminal or the output terminal. the second terminal of the transistor being connected to a supply line for the integrated circuit device. and the control terminal of the transistor being connected to ground,wherein the transistor is formed by a structure comprising:a substrate of a first conductivity type;a first region of a second conductivity type, which is opposite the first conductivity type, that extends from a surface of the substrate;a second region of the first conductivity type that extends from the surface into a portion of the first region;a third region of the first conductivity type, the third region having greater conductivity than the substrate and having a portion buried beneath the first region and another portion extending to the surface, the entire third region being isolated from the first region; anda fourth region of the second conductivity type, the fourth region having greater conductivity than the first region and extending from the second region with a ring shape so as to form a bipolar junction with the second region in an area beneath a non-peripheral portion of the second region.