FET device having ultra-low on-resistance and low gate charge

A metal-oxide-semiconductor field effect transistor (MOSFET) comprising:

• a heavily doped substrate of a first conductivity type;
• a heavily doped substrate cap region of the first conductivity type disposed on the heavily doped substrate;
• a body region disposed on the heavily doped substrate cap region, the body region including a lightly doped epitaxial layer of a second conductivity type;
• an out-diffusion region of the first conductivity type disposed in a lower portion of the body region and in contact with the heavily doped substrate cap region;
• and
• a gate trench extending through the body region, extending through the out-diffusion region and terminating in the heavily doped substrate.

A metal-oxide-semiconductor field effect transistor (MOSFET) comprising:

• a substrate of a first conductivity type;
• a substrate cap region disposed on the substrate, the substrate cap region including a first epitaxial layer of the first conductivity type;
• a body region disposed on the substrate cap region, the body region including a second epitaxial layer of a second conductivity type;
• an out-diffusion region of the first conductivity type disposed in a lower portion of the body region and in contact with the substrate cap region;
• and
• a gate trench extending through the body region, extending through the out-diffusion region and terminating in the substrate.