Patent ID: 7986010

Claim:
An electrostatic discharge (ESD) protection device having a desired breakdown voltage (BV), comprising: a semiconductor substrate having a first electrical conductivity type and a top surface; a deep well having a second electrical conductivity type formed in the substrate; a shallow well having the second electrical conductivity type formed in the deep well; the shallow well having a higher dopant concentration than the deep well; a junction of the deep well with the shallow well at the top surface defining a first surface junction; and a junction of the deep well with the substrate at the surface defining a second surface junction; an isolation region in the surface formed following formation of the deep well and the shallow well; the isolation region covering the first surface junction and a partial portion of the surface extending from the first surface junction to the second surface junction; and one of an anode or cathode region formed in the shallow well; the one of the anode or cathode region being of the second electrical conductivity type and having a higher dopant concentration than the shallow well; wherein the breakdown voltage is established by the amount of the partial portion covered by the isolation region.