Semiconductor device

A manufacturing method of a semiconductor device, comprising:

• providing a semiconductor layer having first and second surfaces and including a first semiconductor region of a first type;
• forming a first trench through the first surface;
• forming a second trench through the first surface, the second trench being shallower than the first trench;
• forming a first insulation region in the first trench;
• forming a second insulation region in the second trench;
• forming a first conductive portion in the first insulation region;
• forming a control electrode in the second insulation region;
• forming a second semiconductor region of the first type along the first surface and between the first and second insulation regions;
• forming a third semiconductor region of a second type such that the control electrode and the second insulation region is between the second and third semiconductor regions;
• forming a fourth semiconductor region of the first type between the third semiconductor region and the first surface;
• removing a part of the first insulation region adjacent to the second semiconductor region along the first surface and forming a second conductive portion, which is a Schottky barrier metal;
• removing a part of the third and fourth semiconductor regions and forming a contact portion;
• cover the first surface except for the contact portion with an insulation film;
• and
• forming a first electrode on the insulation film and the contact portion.