An electronic device includes a stack structure, the stack structure including at least one deck including tiers of vertically alternating dielectric materials and conductive materials, an opening extending through the at least one deck, a compressive dielectric material disposed on a bottom surface defining the opening and on sidewalls of the tiers defining the opening, and a dielectric material in direct contact with the compressive dielectric material. The dielectric material substantially fills a remainder of the opening. The compressive dielectric material exhibits a horizontal compressive force against the tiers. Related methods and systems are also disclosed.