| 摘要 |
An SiO2 layer and an SiN layer are alternately stacked in regions 1 and 2 where the wiring film must be thin and thick, respectively, in such a manner that the stacked SiO2 and SiN layers constitute first through sixth interlayer insulating films. The SiN layer may be replaced with a layer of another material having an etching selection ratio with reference to SiO2. Then, resist having a cutout pattern is formed. The cutout pattern has a first via pattern in the first region and a first wiring pattern in the second region. With this resist used as a mask, the sixth, fifth, fourth and third insulating films are etched. Further, second resist having a cutout pattern is formed. The cutout pattern of the second resist has a second wiring pattern in the first region and a second via pattern in the second region. With the second resist used as a mask, the sixth and fifth insulating films are etched in the first region, and the second and first insulating films are etched in the second region. Simultaneous with this, the second and first insulating films are etched in the first region in accordance with the first via pattern. In this manner, the wiring film is thinner in the first region where the capacitance of micro wiring patterns should be suppressed than in the second region where a low resistance is required. |
