An embodiment of a method for manufacturing a power device with conductive gate structures inside etched trenches. Such trenches include sidewalls and a bottom, wherein covering the sidewalls and the bottom of the trench is a first insulating coating layer. In the formation of the conductive gate structure, openings within the first material in the trench are made such that a conductive central region of a second conductive material having a different resistivity than the first conductive material are able to be electrically coupled together through a plurality of conductive bridges between said second conductive coating layer and said conductive central region.