Semiconductor memory devices

A semiconductor memory device includes a substrate including a memory cell region, a plurality of capacitor structures arranged in the memory cell region of the substrate and including a plurality of lower electrodes, a capacitor dielectric layer, and an upper electrode, a first support pattern contacting sidewalls of the plurality of lower electrodes of the plurality of capacitor structures to support the plurality of lower electrodes, and a second support pattern located at a higher vertical level than a vertical level of the first support pattern and contacting the sidewalls of the plurality of lower electrodes to support the plurality of lower electrodes. The plurality of lower electrodes have a plurality of recessed electrode portions, respectively, in upper portions of the plurality of lower electrodes.