| 摘要 |
PURPOSE:To form a high capacity capacitor whose capacitor insulating film consisting of tantalum oxide, etc., having a high dielectric constant by substituting only the surface of a storage electrode with tungsten. CONSTITUTION:There are provided an interlayer insulating film 7, a TiN layer 8 which is a barrier metal formed by reactive sputtering to be contiguous to a high concentration diffusion layer 5 through a contact hole, a tungsten layer 9 formed by substituting a second layer polycrystalline silicon with tungsten, and a tungsten layer 12 formed by substituting a third polycrystalline silicon with tungsten through a contact hole after forming an interlayer insulating film 11. Further, a Ta2O3 film 13 is formed to cover the surface of the tungsten layer 12, and a tungsten layer 14 which is a plate electrode is formed on this Ta2O3 film 13. Thus, polycrystalline silicon can be substituted with tungsten by heat treating with tungsten fluoride, so that a high capacity capacitor can be realized. |
