Method of making a grooved gate structure of semiconductor device

Abstract

A method is capable of providing a semiconductor device with a gate having thereon a thicker silicide or metal layer and further having a lower interconnect resistance. The method is further capable of providing the semiconductor device with a polysilicon gate having a recessed tungsten structure for prevention of short circuit between the gate and the drain or the source. For forming a grooved gate structure, a photo-resist is formed on the polysilicon gate before growing on the entire surface of the silicon substrate a silicon dioxide layer. The silicon dioxide layer and the thin gate oxidation layer on drain/source are etched vertically by a reactive ion etching until the photo-resist and the silicon surface of drain/source are exposed. A plurality of spacers are thus formed on the side walls of the photo-resist/polysilicon gate. Upon stripping the photo-resist, the grooved gate structure is formed on the semiconductor device.