SEMICONDUCTOR DEVICE FOR HIGH-VOLTAGE POWER

摘要

PROBLEM TO BE SOLVED: To provide a semiconductor device for high-voltage power that has reduced useless space, is easy to be formed, and has short working process time.SOLUTION: A semiconductor device for high-voltage power includes: a first first-conductivity-type semiconductor layer (high-resistance Nlayer) 1; a first second-conductivity-type layer (P layer) 2 selectively formed on one surface of the first first-conductivity-type semiconductor layer 1; a second first-conductivity-type layer (Nlayer) 3 formed on the other surface of the first first-conductivity-type semiconductor layer 1; a trench 4 formed in contact with the first second-conductivity-type layer 2; an insulator 5 in the trench 4; a second second-conductivity-type layer (P layer) 6 formed on a side wall and a bottom of the trench 4; and a third first-conductivity-type layer (Nlayer) 7 selectively formed on the bottom of the trench 4. A depletion layer does not spread to a termination portion of the first first-conductivity-type semiconductor layer 1 by the third first-conductivity-type layer 7 and a termination distance becomes shorter, so that the width of the semiconductor device can be reduced by cutting the termination portion of the first-conductivity-type semiconductor layer 1.