Methods, systems, and devices for sparse piers for three-dimensional memory arrays are described. A semiconductor device, such as a memory die, may include pier structures formed in contact with features formed from alternating layers of materials deposited over a substrate, which may provide mechanical support for subsequent processing. For example, a memory die may include alternating layers of a first material and a second material, which may be formed into various cross-sectional patterns. In some examples, the alternating layers may be formed into one or more pairs of interleaved comb structures. Pier structures may be formed in contact with the cross sectional patterns to provide mechanical support between instances of the cross-sectional patterns, or between layers of the cross-sectional patterns (e.g., when one or more layers are removed from the cross-sectional patterns), or both.