| 摘要 |
PROBLEM TO BE SOLVED: To provide an SiC Schottky barrier diode having high avalanche resistance while having a desired high withstand voltage.SOLUTION: A silicon carbide Schottky barrier diode includes a Schottky electrode 3 on a surface of a silicon carbide layer 2 of a first conductivity type, and includes a guard ring layer formed so as to be partially overlapped around the Schottky electrode. The guard ring layer includes a first guard ring region 8 and a second guard ring region 9 comprising a region where impurity ions forming a second conductivity type are injected in the silicon carbide layer of a first conductivity type to be recrystallized and a part of the injected impurity ions are activated to exhibit a second conductivity type. A second guard ring layer is disposed so as to cover the lower part or the outer peripheral side surface of the first guard ring region and not to overlap around the Schottky electrode. The impurity concentration in the second guard ring region is lower than that in the first guard ring region. |
