A method for fabricating a capacitor includes forming an isolation layer over a cell region and a peripheral region of a substrate. The isolation layer forms a plurality of open regions in the cell region. Storage nodes are formed on surfaces of the open regions. An upper portion of the isolation layer is etched to expose upper outer walls of the storage nodes. A sacrificial pattern is formed over the isolation layer to enclose the upper outer walls of the storage nodes. The isolation layer in the peripheral region is etched to expose side portions of the resulting structure obtained after forming the sacrificial pattern in the cell region. With the sacrificial pattern supporting the storage nodes, the isolation layer in the cell region is removed. The sacrificial pattern is then removed.