Semiconductor storage device and method for manufacturing the same
US7696553B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Sep 12, 2006 |
| Grant date | Apr 13, 2010 |
| Priority date | — |
| Expiry date | Dec 30, 2026 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH10B12/315
Abstract
A semiconductor storage device is manufactured by the following steps. A cylindrical hole is formed in an interlayer insulating film. Then, a multilayer conductive layer including a first sublayer and a second sublayer is formed over the entire surface of the insulating interlayer including the internal surface of the hole. The second sublayer has a higher nitrogen content than the first sublayer. A cup-like lower electrode is formed by reactive ion etching of the conductive layer under conditions that the second sublayer is etched faster than the first sublayer, so that the conductive layer remains only on the internal surface of the hole, and so that the upper edge of the remaining conductive layer forms an angle of 45° or less with the internal wall of the hole. Then, a capacitor insulating layer and an upper electrode are formed in that order on the lower electrode.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.