HIGH BREAKDOWN VOLTAGE TRANSISTOR, SEMICONDUCTOR DEVICE USING THE SAME, AND MANUFACTURING METHOD OF HIGH BREAKDOWN VOLTAGE TRANSISTOR

摘要

PROBLEM TO BE SOLVED: To prevent a gate oxide film from being broken by surge voltages/currents. SOLUTION: The high breakdown voltage transistor comprises: a gate electrode 4 provided in a trench formed on a semiconductor substrate 8; a source 5 and a drain 6 formed with a prescribed interval from the gate electrode 4 at both the sides of the gate electrode 4; an electric field relaxing layer 2 formed along a sidewall at the side of the source 5 of the trench and along a sidewall at the side of the drain 6 of the trench; and an electric field relaxing layer 3 formed between the gate electrode 4 and the source 5, and between the gate electrode 4 and the drain 6. COPYRIGHT: (C)2008,JPO&INPIT