Abstract: A method for avoiding erosion of a conductor structure during a procedure of removing etching residues is provided. The method provides a semiconductor structure and the conductor structure formed therein. A cap layer is formed on the conductor structure and the semiconductor and a dielectric layer formed thereon. The dielectric layer and the cap layer are then etched to partially expose the conductor structure. The etching residues are removed with an amine-containing solution and the amine-containing solution is removed with an intermediate solvent to avoid erosion of the exposed conductor structure. As a key step of the present invention, the intermediate solvent comprises N-methylpyrrolidone or isopropyl alcohol and can protect the conductor structure from erosion.

Abstract: A method for increasing tolerance of contact extension alignment in a capacitor over a bit line of a dynamic random access memory is disclosed. Firstly, a substrate having a gate, a bit line and a source/drain region is provided and a insulating layer is formed on the substrate. Then, a dielectric layer is deposited on the insulating layer. Moreover, a contact hole is formed by defining and etching the dielectric layer and the insulating layer to expose a portion of the source/drain region. Furthermore, a conductive layer is deposited on the dielectric layer and the contact hole, wherein the etching selectivity ratio of the conductive layer is near the etching selectivity ratio of the dielectric layer. Finally, an electrode of the capacitor is formed by defining and etching the conductive layer, whereby the dielectric layer protects the portion of the electrode that is beneath the dielectric layer from being etched when misalignment occurs.