SEMICONDUCTOR ELEMENT

PROBLEM TO BE SOLVED: To provide a semiconductor element which can solve a problem of concentration of an electric field and a current on a part of PN junction.SOLUTION: A semiconductor element comprises: a semiconductor substrate 10 of a first conductivity type; an active region 12 of a second conductivity type formed on an upper surface side of the semiconductor substrate; an inside VLD region 14 of the second conductivity type formed on the upper surface side of the semiconductor substrate so as to contact the active region in planar view; and a well region 16 of the second conductivity type formed on the upper surface side of the semiconductor substrate so as to contact a part of the inside VLD region opposite to a part which contacts the active region. The well region is formed deeper than the active region, and the inside VLD region has a depth which is the same with that of the active region at the part which contacts the active region, and gradually increases from the active region to the well region and the same with that of the well region at the part which contacts the well region. 【課題】 本発明は、ＰＮ接合の一部に電界及び電流が集中する問題を解消できる半導体素子を提供することを目的とする。【解決手段】第１導電型の半導体基板１０と、該半導体基板の上面側に形成された第２導電型の活性領域１２と、該半導体基板の上面側に平面視で該活性領域と接するように形成された第２導電型の内側ＶＬＤ領域１４と、該半導体基板の上面側に平面視で該内側ＶＬＤ領域の該活性領域と接する部分と反対側の部分と接するように形成された第２導電型のウェル領域１６とを備える。該ウェル領域は該活性領域よりも深く形成され、該内側ＶＬＤ領域は、該活性領域と接する部分では該活性領域と同じ深さであり、該活性領域から該ウェル領域に向かって深さが漸増し、該ウェル領域と接する部分では該ウェル領域と同じ深さとなる。【選択図】図１