| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a technique that prevents the concentration of current near the outer peripheral end of a contact region during a recovery operation. <P>SOLUTION: In a diode 10, a P-type high concentration region 30a is located under a first surface 12a of a semiconductor substrate 12. A P-type intermediate concentration region 30b is located spaced apart from the high concentration region 30a under the first surface 12a of the semiconductor substrate 12. A low concentration region 30c covers the side surfaces and the bottom surfaces of the high concentration region 30a and the intermediate concentration region 30b and isolates the high concentration region 30a and the intermediate concentration region 30b. An N-type drift region 50a contacts the low concentration region 30c and is isolated from the high concentration region 30a and the intermediate concentration region 30b. An anode electrode 14 does not contact the intermediate concentration region 30b, but contacts the high concentration region 30a. The impurity concentration of the high concentration region 30a is higher than that of the intermediate concentration region 30b. The impurity concentration of the intermediate concentration region 30b is higher than that of the low concentration region 30c. <P>COPYRIGHT: (C)2012,JPO&INPIT |
