METHOD FOR PRODUCING A SEMICONDUCTOR POWER DEVICE (DMOS) INCLUDING GATE ELECTRODE FORMED OVER A GATE INSULATION FILM HAVING SiO2 PORTIONS AND A HIGH-K PORTION THEREBETWEEN

摘要

A method for producing a semiconductor power device, includes forming a gate trench from a surface of a semiconductor layer toward an inside thereof. A first insulation film is formed on an inner surface of the gate trench. The method also includes removing a part on a bottom surface of the gate trench in the first insulation film. A second insulation film having a dielectric constant higher than SiO2 is formed in such a way as to cover the bottom surface of the gate trench exposed by removing the first insulation film.

主权项

1. A method for producing a semiconductor power device, the semiconductor power device having a semiconductor layer and a trench-gate type transistor structure formed in the semiconductor layer, the trench-gate type transistor structure comprising: a first conductivity type source region; a second conductivity type body region contiguous to the source region; a first conductivity type drift region contiguous to the body region; a gate trench formed in such a way as to straddle the source region, the body region, and the drift region; a gate insulation film formed on an inner surface of the gate trench; and a gate electrode facing the body region with the gate insulation film therebetween, the method comprising:
a step of forming the gate trench from a surface of the semiconductor layer toward an inside thereof; a step of forming a first insulation film on the inner surface of the gate trench; a step of removing a part on a bottom surface of the gate trench in the first insulation film; and a step of forming a second insulation film having a dielectric constant higher than SiO2 in such a way as to cover the bottom surface of the gate trench exposed by removing the first insulation film.