| 摘要 |
Disclosed are embodiments for a container capacitor structure in which at least two container capacitors, e.g., an inner and outer container capacitor, are made concentric and nested with respect to one another. The nested capacitors are formed in one embodiment by defining a hole in a dielectric layer for the nested container capacitors in the vicinity of two capacitor contact plugs. An outer capacitor plate is formed by etching back poly 1 to leave it substantially on the vertical edges of the hole and in contact with one of the plugs. At least one sacrificial sidewall is formed on the poly 1, and poly 2 is deposited over the sidewalls to form an inner capacitor plate in contact with the other plug. The structure is planarized, the sacrificial sidewalls are removed, a capacitor dielectric is formed, and is topped with poly 3. Additional structures such as a protective layer (to prevent poly 1-to-poly 2 shorting) and a conductive layer (to strap the plugs to their respective poly layers) can also be used.
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