| 摘要 |
PURPOSE:To smooth the shape of the side surface of a polysilicon pattern, eliminate an overhang of a CVD-SiO2 film and to reduce the disconnection of wires made of aluminum or the like by the different etching speed of a multilayer polysilicon film. CONSTITUTION:First polysilicon patterns 24a, 24a', second polysilicon patterns 25a, 25a' and third polysilicon patterns 26a, 26a' are sequentially reduced in size in this order due to the difference of impurity density in the polysilicon to smooth the configuration of three layer polysilicon patterns in the side surfaces. Therefore, when forming CVD-SiO2 film, since the configuration of the side surfaces of the polysilicon patterns are smoothed, no overhang occurs on the side surfaces to reduce the disconnection of the aluminum wires. |
