| 摘要 |
PURPOSE:To obtain a capacitance element having large capacitance in spite of a small area by using a nitride film as a dielectric constituting the capacitance element when the IC memory is formed by connecting an IGFET and the capacitance element in series. CONSTITUTION:The surface of a P type Si substrate 1 is coated with a SiO2 gate insulating film 2 with approximately 300Angstrom thickness, and gate electrodes 3, 4 consisting of polycrystalline Si to which phosphorus is added are formed onto the film 2. These electrodes 3, 4 are each coated with Si3N4 films 7, 8 forming an active region through SiO2 films 5, 6 with approximately 100Angstrom thickness, and thick SiO2 films 9 are formed to the central section and periphery of the active region through heat treatment while using P<+> type regions 10 for preventing a parasitic effect as underlays. A capacitance element electrode 11 using polycrystalline Si to which phosphorus is added is formed onto the upper surfaces of the films 7, 8 and coated with an SiO2 film 12 with approximately 5,000Angstrom thickness, N type regions 13, 14 being in contact with the peripheral region 10 are formed through ion implantation, and the whole surface is coated with an Al wiring electrode 15. |
