Semiconductor device and manufacturing method for semiconductor device

A manufacturing method for a semiconductor device, comprising:

• forming an epitaxial layer of a first conductivity type on a semiconductor substrate of the first conductivity type;
• forming an element isolation region in a predetermined region on the epitaxial layer;
• forming a gate electrode filled in a trench formed on the epitaxial layer;
• forming a column region of a second conductivity type in the epitaxial layer;
• forming a base region of a second conductivity type on the epitaxial layer;
• forming a source region of the first conductivity type in a predetermined region on the base region;
• forming an interlayer insulating film throughout an entire surface of the semiconductor substrate;
• forming a contact hole passing through the interlayer insulating film to expose the gate electrode on a surface;
• forming a gate electrode plug using a conductor filled in the contact hole;
• and
• forming a gate wiring metal connected with the gate wiring metal on the interlayer insulating film.