METHOD FOR FORMING LOWER ELECTRODES OF CYLINDER-SHAPED CAPACITOR

摘要

PURPOSE: A method for forming lower electrodes of a cylinder-shaped capacitor is provided to prevent the lower electrodes being connected or to prevent an interval between lower electrodes being narrow, and to increase a process margin rate by preventing an unnecessary electric flow between the low electrodes. CONSTITUTION: A method for forming lower electrodes of a cylinder-shaped capacitor comprises the steps of: forming first conductive layers(21) and sacrifice insulating layers(22) on a semiconductor substrate(20); forming etching masks on the sacrifice insulating layers; making pattern width of the first conductive layers narrower than the pattern width of the sacrifice insulating layers, by etching the first conductive layers and the sacrifice insulating layers in a condition as etching selection ratios of the first conductive layers for the sacrifice insulating layers are bigger; removing the etching masks; making equal the pattern width of the first conductive layers with the pattern width of the sacrifice insulating layers, by performing a wet etching process for eliminating impurities; and forming second conductive layers(24) on whole structure, and forming spacers of the second conductive layers on side walls of the sacrifice insulating layers and on side walls of the first conductive layers, by etching the second conductive layers; and removing sacrifice oxide layers.