| 摘要 |
Disclosed is a wide-gap semiconductor composite diode wherein p+ type anode layers (3a, 3b) are epitaxially grown on an n- type drift layer (2), then the anode layers are processed into mesa-shapes, and one or more pn junctions are provided. On the mesa bottom portion, Schottky junctions (7a, 7b) are provided at a distance from pn main junctions (5a, 5b). Thus, defects and influences of the defects, which are generated in the Schottky junctions (7a, 7b) due to defects generated in both the junctions when being formed and stress is applied by wire bonding, are reduced. A p type integrated electric field relaxing layer (13) having a concentration lower than that of the p+ type anode layers (3a, 3b) is provided between the junctions such that the p type integrated electric field relaxing layer is in contact with both the junctions. A high withstand voltage is achieved by suppressing the generation of the defects. Furthermore, accumulated carriers remaining under the pn junctions (5a, 5b) are efficiently discharged without deteriorating the high withstand voltage, and a reverse recovery time and a reverse recovery current are reduced by disposing the Schottky junctions (7a, 7b) on the outermost circumferential portions of both the junctions, and by providing the p type integrated electric field relaxing layer (13) connected to the Schottky junctions. |
