| 摘要 |
The self-aligned stacked capacitor structure and its fabricating process are disclosed. Transistor is formed on the substrate and an oxide layer used for buried contact etch, an undoped polysilicon layer and an oxide layer used for increasing of capacitance are formed on the substrate successively. And a mask is formed on the oxide layer used for increasing of capacitance and then the oxide layer used for increasing of capacitance is etched vertically and the undoped polysilicon layer is etched isotropically to form a protrusive structure, then the mask is removed and the oxide used for buried contact etch is etched selectively to form a buried contact on the impurity region of the transistor. Polysilicon is deposited on the entire surface of the protrusive structure and then a photoresist is coated and etched to expose the oxide used for increasing of capacitance. Then the photoresist is removed and the oxide used for increasing of capacitance is etched by wet etch, and a capacitor dielectric layer and a plate electrode are formed, thereby a cave shaped capacitor having a large capacitance is obtained.
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