Medium High Voltage MOSFET Device

摘要

A semiconductor device includes a medium voltage MOSFET having a vertical drain drift region between RESURF trenches containing field plates which are electrically coupled to a source electrode of the MOSFET. A split gate with a central opening is disposed above the drain drift region between the RESURF trenches. A two-level LDD region is disposed below the central opening in the split gate. A contact metal stack makes contact with a source region at lateral sides of the triple contact structure, and with a body contact region and the field plates in the RESURF trenches at a bottom surface of the triple contact structure. A perimeter RESURF trench surrounds the MOSFET. A field plate in the perimeter RESURF trench is electrically coupled to the source electrode of the MOSFET. An integrated snubber may be formed in trenches formed concurrently with the RESURF trenches.

主权项

1. A method, comprising:
forming a drain drift region in a substrate; forming a body region on the drain drift region; forming a source region in the body region; forming a gate above the source region, the body region and the drain drift region, and free from overlapping any conductor positioned within the substrate; and forming a trench extending from the body region to the drain drift region, the trench having a conducting plate coupled to the source region and the body region, and a dielectric liner insulating the conducting plate from the drain drift region.