| 摘要 |
PURPOSE:To reduce completely the step of a projected pattern, which spreads in the horizontal direction on a large scale, by a method wherein interlayer insulating films are respectively provided in such a way as to cover parts of the high density of wirings and parts of the low density of wirings, which spread in the horizontal direction on a substrate, and the irregularity in the heights of the surfaces of these interlayer insulating films from the surface of the substrate is specified. CONSTITUTION:A region 16, which has the high density of wirings, of a second interlayer insulating film 27 is formed of a silicon oxide film 18, a silicon nitride film 19 and a silicon oxide film 21, which are laminated in order from the lower part of the region 16, and a region 26, which has the low density of wirings, of the film 27 is formed of the film 18, the film 19, a PSG film 20 and the film 21, which are laminated in order from the lower part of the the region 26. A third interlayer insulating film 37 and a fourth interlayer insulating film 47 also have the same structure as that of the film 27. The irregularity in the heights of the surfaces of a first interlayer insulating film 17 and the films 27, 37 and 47 from the surface of a silicon substrate 1 is set within + or -0.3mum. Thereby, a semiconductor device with flattened surface is formed. |
