Microelectronic devices with active source/drain contacts in trench in symmetrical dual-block structure, and related systems and methods

Abstract

Microelectronic devices include a tiered stack having vertically alternating insulative and conductive structures. A first series of stadiums is defined in the tiered stack within a first block of a dual-block structure. A second series of stadiums is defined in the tiered stack within a second block of the dual-block structure. The first and second series of stadiums are substantially symmetrically structured about a trench at a center of the dual-block structure. The trench extends a width of the first and second series of stadiums. The stadiums of the first and second series of stadiums have opposing staircase structures comprising steps at ends of the conductive structures of the tiered stack. Conductive source/drain contact structures are in the stack and extend substantially vertically from a source/drain region at a floor of the trench. Additional microelectronic devices are also disclosed, as are methods of fabrication and electronic systems.