| 摘要 |
PURPOSE:To surely prevent the wiring from being disconnected by a method wherein a laminated film of a second silicon oxide film and a third silicon oxide film, whose silicon components are respectively different, is used as an interlayer insulating film and a contact hole is formed by successively applying etching methods, which differ in etching speed. CONSTITUTION:First conductor wirings 13 are formed on a semiconductor substrate 11, and recessed parts between the wirings are filled first with a first silicon oxide film 14 formed by a CVD method and are flattened. After this, a second silicon oxide film 15, wherein silicon has been contained in surplus, is deposited on the whole surface by a CVD method, whose conditions have been made to differ from those of the aforesaid CVD method. Following that, the conditions are returned to the former ones in the same reaction furnace and a third silicon oxide film 16 is continuously deposited. A mask 17 to be used for opening a contact hole is formed. First, a selective etching is performed on the third silicon oxide film 16 by a first etching method, whose etching speed is faster than that to the second silicon oxide film 15, then a selective etching is performed on the second silicon oxide film 15 by a second etching method, whose etching speed is faster than that to the first and third silicon oxide films 14 and 16, and a contact hole is opened. |
