Method and a circuit for improving the effectiveness of ESD protection in circuit structures formed in a semiconductor

摘要

A method and a related circuit structure are described for improving the effectiveness of ESD protection in circuit structures realized in a semiconductor substrate overlaid with an epitaxial layer and including at least one ESD protection lateral bipolar transistor realized in the surface of the epitaxial layer. The method consists of forming under the transistor an isolating well that isolates the transistor from the substrate. Advantageously, the transistor can be fully isolated from the substrate by first and second N wells which extend from the surface of the epitaxial layer down to and in contact with the buried well.