| 摘要 |
PURPOSE:To double electrostatic capacity by a rugged silicon plane generated after titanium silicide removal by laminating titanium and removing the agglomerated titanium silicide by heat process when forming a capacitor on a silicon substrate. CONSTITUTION:An element separating insulating film 3, a word line polysilicon film 4 and an insulating film 5 are formed on a silicon substrate 1, and the substrate 1 is coated with an N-type polysilicon film 6 to be the negative electrode of a capacitor. When a Ti film 7 is sputtered on the negative electrode, heat processed in N2, for a short period to form a TiSi2 film 8, a TiN film 9 is formed on it. The film 9 is chemically etched and the surface is coated with a BPSG film 10. When it is heat processed at a high temperature, the TiSi2 film is agglomerated to be powder. When the BPSG film and the TiSi2 film are removed by chemical etching, the rugged surface of the negative electrode polysilicon 6 is produced. When an insulating layer 11 and a positive electrode polysilicon film 12 are formed, a DRAM which has double capacity by the same cross-section area is produced. |
