Microelectronic devices including interconnections, related memory devices and electronic systems

Abstract

A microelectronic device comprises a stack structure comprising blocks each including a vertically alternating sequence of conductive material and insulative material arranged in tiers, at least one of the blocks comprising: a memory array region having vertically extending strings of memory cells within a horizontal area thereof; and a staircase region horizontally neighboring the memory array region. The staircase structure has steps comprising horizontal ends of the tiers; and a crest sub-region horizontally interposed between the staircase structure and the memory array region. A masking structure overlies the stack structure and has a different material composition than each of the conductive material and the insulative material. Filled slot structures are interposed between the blocks of the stack structure, at least one of the filled slot structures comprises at least one fill material that has an uppermost boundary vertically underlying an uppermost boundary of the masking structure.