Gate structure with low resistance for high power semiconductor devices

摘要

In accordance with an embodiment of the present invention, a gate structure for a U-shape Metal-Oxide-Semiconductor (UMOS) device includes a dielectric layer formed into a U-shape having side walls and a floor to form a trench surrounding a dielectric layer interior region, a doped poly-silicon layer deposited adjacent to the dielectric layer within the dielectric layer interior region where the doped poly-silicon layer has side walls and a floor surrounding a doped poly-silicon layer interior region, a first metal layer deposited on the doped poly-silicon layer on a side opposite from the dielectric layer where the first metal layer has side walls and a floor surrounding a first metal layer interior region, and an undoped poly-silicon layer deposited to fill the first metal layer interior region.