Patent ID: 7696580
Filing Date: 2010-04-13
Classification: H01L

Abstract:
1. An apparatus, comprising: a semiconductor substrate of a first conductivity type; a buried layer of a second conductivity type formed in the semiconductor substrate; a well of the first conductivity type formed on the buried layer; a connection region of the second conductivity type formed on the buried layer; two isolation regions, respectively formed in the substrate on two sides of the buried layer, wherein at least one of the isolation regions extends further into the substrate than the buried layer, and wherein the isolation regions together with the buried layer isolate the well and the connection region from the semiconductor substrate; a first doped region of the second conductivity type formed in the well and configured to provide a first electrode of a first diode; a second doped region of the second conductivity type formed at least partially in the connection region; and a third doped region of the first conductivity type formed at least partially in the well and contacting the second doped region; wherein the connection region and the well are configured to be electrically connected and to provide a second electrode of the first diode.