Semiconductor device and method for manufacturing same

A method for manufacturing a semiconductor device, comprising:

• applying an n-layer to an n+ substrate;
• creating trenches in the n-layer;
• covering the trenches with an oxide layer;
• removing the oxide layer from bottoms of the trenches and also from a portion of walls of the trenches;
• filling portions of the trenches freed of the oxide layer with p-doped Si or poly-Si to form p regions;
• and
• covering the n+ substrate and the n-layer with contact layers, the regions of the trenches not filled with p regions being filled completely with a material of the contact layer.

A method for manufacturing a semiconductor device, comprising:

• applying an n-layer to an n+ substrate;
• creating in the n-layer;
• covering the trenches with an oxide layer;
• removing the oxide layer from bottoms of the trenches in some areas;
• covering a portion of the bottoms of the trenches freed of the oxide layer with a dopant substance;
• performing a diffusion process to form p regions disposed beneath the trenches;
• and
• covering the n+ substrate and the n-layer with contact layers, the trenches being completely filled with a material of the contact layer.