METHOD FOR MANUFACTURING CAPACITOR OF SEMICONDUCTOR DEVICE

摘要

PURPOSE: A method for manufacturing a capacitor of a semiconductor device is provided to achieve sufficiently CD(Critical Dimension) at the bottom of a capacitor and to improve step coverage at sides of capacitor by using a multilayer capacitor oxide layer. CONSTITUTION: A nitride layer(23) is formed on a semiconductor substrate(20) having a plug(22). A multilayer capacitor oxide layer(24) having at least three layers(24A-24C) is formed on the nitride layer. By etching the multilayer capacitor oxide layer and the nitride layer, the plug is exposed. By wet-etching of the multilayer capacitor oxide layer, a capacitor hole(27) having stepped shape is formed. At the time, the multilayer capacitor oxide layer(24) has a different wet-etching selectivity each other.