Patent ID: 7074687
Filing Date: 2006-07-11
Classification: H01L

Abstract:
1. A method of fabricating an ESD protection device, the method comprising: providing collector layer of a first conductivity type; forming a first base region in the collector layer, the first base region having a second conductivity type; forming a second base region in the first base region, the second base region having the second conductivity type; wherein the first base region and the second base region are formed so that the first base region has a depth that is greater than a depth of the second base region and so that the second base region is more highly doped than the first base region; patterning, with a single mask layer, photoresist on the first base region so as to leave exposed a central area having a predetermined lateral dimension; and implanting the central area to form the second base region that has a depth less than the depth of the first base region and has a dopant concentration greater than a dopant concentration of the first base region.