| 摘要 |
PURPOSE: To reduce the surface damage of the silicon substrate of an embedded contact region by wet etching, to improve contactability, and to improve refresh characteristics. CONSTITUTION: An exposed nitride film 28 of an embedded contact region is removed in a wet-etching process by using a second oxide film as a storage node contact mask. The removal of the nitride film 28 is etching-processed, so that it can be engraved until the lower side of the remaining part of a second oxide film 29. Here, a time required for the wet-etching process is adjusted, and engraving depth 1, that is, the area of a capacitor is adjusted. Also, the thickness of the nitride film 28 may be adjusted and controlled. |
