| 摘要 |
PROBLEM TO BE SOLVED: To prevent dropout of a cylinder part in the case of forming a cylindrical memory capacitor. SOLUTION: An SiN etching stopper 22 and a poly Si lower layer electrode material are laminated in order on an SiO2 insulating film 20 covering an MOSFET 12, and then an SiO2 dummy pattern 26 is formed on the lower layer electrode material. It is etched via the dummy pattern 26 by dry etching, and a lower layer electrode protrusion 28 having an overhang type side wall 28a is formed. A poly Si side wall forming material is laminated on the dummy pattern 26, and then etched by anisotropic etching. Thus a side wall is formed in a region from the side wall 28a of the lower layer electrode protrusion 28 to the side wall 26a of the dummy pattern 26. Next, the dummy pattern 26 is eliminated by etching. In this case, when the side wall is peeled from the lower layer electrode protrusion 28, the side wall is caught in the overhang type side wall 28a, so that the dropout of the side wall can be prevented. |
