INCREASE OF EPITAXY RESISTIVITY AND DECREASE OF JUNCTION CAPACITANCE BY ADDITION OF PBURIED LAYER

摘要

An overvoltage protection device including: a doped substrate of a first conductivity type having a first doping level, coated with a doped epitaxial layer of the second conductivity type having a second doping level; a first doped buried region of the second conductivity type having a third doping level greater than the second level, located at the interface between the substrate and the epitaxial layer in a first portion of the device; and a second doped buried region of the first conductivity type having a fourth doping level greater than the first level, located at the interface between the substrate and the epitaxial layer in a second portion of the device.