Patent ID: 7635909

Claim:
A semiconductor diode comprising: an anode, a cathode, a semiconductor structure disposed between the anode and the cathode, the semiconductor structure including first, second, third and fourth semiconductor layers arranged in sequence from the cathode to the anode, the first semiconductor layer being n + -doped, the second semiconductor layer being n-doped, the third semiconductor layer being n − -doped and the fourth semiconductor layer being p-doped, the semiconductor structure further comprising a plurality of spaced apart semiconductor zones, each of the plurality of semiconductor zones being inversely doped with respect to the immediate surroundings thereof, each of the semiconductor zones proximate to and spaced apart from the cathode, wherein the third semiconductor layer is configured to include a flooding charge, and separate junctions are formed between the third and fourth semiconductor layers and between the second and third semiconductor layers, respectively, and wherein a distance between the semiconductor zones and the junction between the second and the third semiconductor layers is smaller than a distance between the fourth semiconductor layer and the second semiconductor layer, wherein the semiconductor zones are located only in the second semiconductor layer.