| 摘要 |
This invention is a cup-shaped capacitor having an inwardly-overhanging lip on the upper edge of the cylindrical wall portion of the cup, as well as a method for making the capacitor. The overhanging lip on the upper edge prevents sharpening of the upper edge during singulation of the storage-node capacitor plates and the attendant problems. The capacitor is formed by depositing a mold layer on a substrate, depositing an etch stop layer on top of the mold layer (the etch stop layer having an etch rate that is lower than that of the mold layer), enlarging the mold layer portion of the cavity such that the mold layer is recessed beneath the edge of the etch stop layer, depositing a first capacitive layer which covers the upper surface of the etch stop layer and fully lines the cavity, performing an isotropic etch-back step which removes at least the portion of the first capacitive layer which overlies the upper surface of the etch stop layer to form a singulated first capacitive plate, removing the etch stop layer, removing at least a portion of the mold layer to expose an outer surface of the first capacitive plate, depositing a dielectric layer, and depositing a second capacitive layer.
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