Sic-based trench-type schottky device

A SiC-based trench-type Schottky device comprising:

• a SiC substrate having a first surface and an opposing second surface;
• a first contact metal formed on the second surface of the SiC substrate and configured for forming an ohmic contact between the first contact metal and the SiC substrate;
• a SiC drift layer formed on the first surface of the SiC substrate and including a cell region and a termination region enclosing the cell region;
• a plurality of first spaced trenches with a first depth formed in the cell region;
• a plurality of second spaced trenches with a second depth formed in the termination region, where in the second depth is less than the first depth;
• a plurality of mesas formed in the SiC drift layer, each defined between neighboring ones of the first and the second spaced trenches;
• a second contact metal layer formed on the mesas and configured for forming a first Schottky contact between the second contact metal layer and the mesas of the SiC substrate;
• and
• a third contact metal formed on sidewalls and bottoms of the first and the second spaced trenches and configured for forming a second Schottky contact between the third contact metal and the sidewalls and bottoms of the first and the second spaced trenches of the SiC substrate;
• wherein work function of the second contact metal layer is less than that of the third contact metal.