| 摘要 |
A method for fabricating a crown-shaped DRAM capacitor comprising the steps of providing a substrate having transistors already formed thereon, then sequentially forming a first insulating layer and a second insulating layer over the substrate and the transistors. The second insulating layer has an upper opening that exposes portions of the first insulating layer, and the first insulating layer has a contact opening that exposes a source/drain region in the substrate. Thereafter, a first conducting layer is formed over the second insulating layer and the exposed first insulating layer. Then, spacers are formed on the sidewalls of the first conducting layer. Next, a second conducting layer is deposited over the first conducting layer and the spacers. Subsequently, the second conducting layer is etched to form conducting pillars next to the spacers. Finally, the spacers and the second insulating layer are removed to form a crown-shaped lower electrode for the capacitor. This invention allows a lower electrode having a large surface area. Therefore, a capacitor with high capacitance is obtained.
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