Patent attributes
The invention is directed to a semiconductor device having a diode element which prevents a leakage current due to a vertical parasitic bipolar transistor and enhances current efficiency. An element isolation insulation film is provided on an N well layer, and a first P+ layer and a second P+ layer are formed on the N well layer surrounded by the element isolation insulation film, the second P+ layer being formed at a distance from the first P+ layer. An electrode layer is formed on the N well layer between the first P+ layer and the second P+ layer. An N+ layer for a contact is formed on the N well layer between the element isolation insulation film and other element isolation insulation film. The first P+ layer is connected with an anode wiring, and the electrode layer, the second P+ layer, and the N+ layer are connected with a cathode wiring. A diode element utilizing a lateral PNP bipolar transistor is thus formed on the semiconductor substrate.
