Method of fabricating a toothed-shape capacitor node using a thin oxide as a mask

摘要

The present invention is a method of fabricating a toothed-shape capacitor node in semiconductor DRAM circuit. This invention utilizes dot silicon formed on a nitride layer as an etching mask. The nitride uncovered by the dot silicon is removed. A first layer of poly-oxide is formed using thermal oxidation. The first poly-oxide layer is removed and a second poly-oxide layer is formed using thermal oxidation. The remaining nitride is removed uncovering the polysilicon. The polysilicon is etched to form trenches in the bottom storage of the capacitor. Finally, the second poly-oxide is removed. Thus, a toothed-shape capacitor node is formed in semiconductor circuit.