| 摘要 |
PURPOSE:To avoid the disconnection failure of metallic wirings by flattening the interlayer insulation film by filling its steps, by providing the process of forming an insulation film over a substrate with semiconductor elements and the process of forming an Si oxide film containing phosphorus and boron so as to fill the steps of the insulation film. CONSTITUTION:A PSG film 7 is formed over the whole surface as the interlayer insulation film by CVD. At this step, steps are generated on the surface of the PSG film 7. An overhang 8 and a constriction 9 are formed in the direction of the side surface of a poly Si gate electrode 4. Next, a Si compound solution 10 containing phosphorus and boron is applied so as to fill steps of the PSG film 7 and then calcined into a BPSG film 11. The flowing temperature of this film 11 is lower than that of a PSG film: it flows by calcination and flattens by filling the steps. At this time, cracks hardly generate in the BPSG film 11. Since boron is diffused to the surface of the PSG film 7 at the time of calcination of the film 11, flowing is caused by the decrease in flowing tempera ture of the surface layer. The surface layer flows particularly at the overhang 8 and is further flattened. |
