1results about How to "Increase electron concentration" patented technology

This invention discloses a silicon carbide-based trench MOSFET with an integrated superjunction structure and its fabrication method. The structure includes an n++ type silicon carbide substrate, an n-type drift layer, a p-type channel layer, a p-type shielding layer, a p++ type source region layer, and an n++ type source region layer. The n-type drift layer is disposed on the first surface of the n++ type silicon carbide substrate. A superjunction structure is integrated below the p-type channel layer and the p-type shielding layer. The superjunction structure includes a first n+ pillar region, a p+ pillar region, and a second n+ pillar region. The first n+ pillar region is located in the middle, and p+ pillar regions are provided on both sides of the first n+ pillar region. A second n+ pillar region is provided on the outer side of each of the two p+ pillar regions. A p-type channel layer is provided on the n-type drift layer on both sides of the superjunction structure and the first trench. Adjacent p++ type source region layers and n++ type source region layers are provided on the p-type channel layer. A gate electrode is provided above the p-type shielding layer. A gate oxide layer is provided between the gate electrode, the p-type shielding layer, and the sidewall of the second trench, which reduces the on-resistance and the electric field in the gate oxide layer at the bottom corner of the trench.