| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To enhance avalanche resistance in a super-junction semiconductor element. <P>SOLUTION: In a semiconductor element including an n<SP>+</SP>-substrate 1 and a parallel pn layer on which an n-region 3 and a p-region 4 are alternately arranged, an n-concentration gradient region 2 having concentration gradient allowing increase of impurity concentration toward the n<SP>+</SP>-substrate 1 from the n-region 3 is provided between the n<SP>+</SP>-substrate 1 and the n-region 3. Therefore, the end part of depletion layer spreads in the high concentration side of the n-concentration gradient region 2 with increase in an avalanche current when an inverse bias is applied. Accordingly, appearance of negative resistance can be prevented by compensating reduction in electric field intensity at the central area of intensified field region caused by increase in the avalanche current. <P>COPYRIGHT: (C)2009,JPO&INPIT</p> |
