| 摘要 |
PURPOSE:To obtain a trench-capacitor structure whose capacitance is large by a method wherein a capacitor is formed at a side wall of an insulating material on a semiconductor substrate and the capacitance is filled into a well formed by a side wall of a gate electrode and by the side wall of the insulating material. CONSTITUTION:A protective film 23 composed of phosphate glass is formed on a polysilicon film 22. A drain contact hole is formed; a silicon oxide film is formed on an inner wall of the contact hole; polysilicon 24 is filled into the contact hole. Then, a capacitor is formed on a side wall of a silicon oxide film 12 as an insulating material formed so as to be exposed on a silicon substrate 11. In addition, a polysilicon film 14 constituting a gate electrode is formed in a highly erected state; a well is formed of the side wall and a side wall of the silicon film 12. The capacitor is filled into the well. By this setup, a trench-capacitor structure whose capacitance is large can be obtained. |
