| 摘要 |
PURPOSE:To ensure a capacity required for memory without varying the size of capacitor electrode and to make the surface of capacitor irregular at a temperature higher a predetermined level. CONSTITUTION:The method for making irregular the surface of polysilicon 2 or amorphous silicon deposited on a semiconductor substrate 1 comprises a step for etching the polysilicon 2 or amorphous silicon using an etching gas containing gases produced from an aqueous solution containing hydrofluoric acid and nitric acid. The method for making irregular the surface of silicon oxide 4 deposited on the semiconductor substrate 1 comprises a step for etching the silicon oxide using an etching gas containing gases produced from an aqueous solution containing hydrofluoric acid. |
