Abstract: Integrated circuitry comprises two three-dimensional (3D) array regions individually comprising tiers of electronic components. A stair-step region is between the two 3D-array regions. First stair-step structures alternate with second stair-step structures along a first direction within the stair-step region. The first stair-step structures individually comprise two opposing first flights of stairs in a first vertical cross-section along the first direction. The stairs in the first flights each have multiple different-depth treads in a second vertical cross-section that is along a second direction that is orthogonal to the first direction. The second stair-step structures individually comprise two opposing second flights of stairs in the first vertical cross-section. The stairs in the second flights each have only a single one tread along the second direction. Other embodiments, including method, are disclosed.

Abstract: A memory array comprising strings of memory cells comprises a vertical stack comprising alternating insulative tiers and conductive tiers. Channel-material strings of memory cells are in the stack. The channel-material strings project upwardly from material of an uppermost of the tiers. A first insulator material is above the material of the uppermost tier directly against sides of channel material of the upwardly-projecting channel-material strings. The first insulator material comprises at least one of (a) and (b), where (a): silicon, nitrogen, and one or more of carbon, oxygen, boron, and phosphorus, and (b): silicon carbide. Second insulator material is above the first insulator material. The first and second insulator materials comprise different compositions relative one another. Conductive vias in the second insulator material are individually directly electrically coupled to individual of the channel-material strings. Other embodiments, including methods, are disclosed.

Abstract: A microelectronic device includes a stack structure including a block region and a non-block region. The block region includes blocks separated from one another in a first horizontal direction by insulative slot structures and each including a vertically alternating sequence of conductive material and insulative material arranged in tiers. At least one of the blocks has stadium structures individually including staircase structures having steps comprising edges of some of the tiers. The non-block region neighbors the block region in the first horizontal direction. The non-block region includes additional stadium structures individually terminating at a relatively higher vertical position within the stack structure than at least one of the stadium structures at least partially within boundaries thereof in a second horizontal direction orthogonal to the first horizontal direction. Related memory devices, electronic systems, and methods are also described.

Abstract: A memory array comprising strings of memory cells comprises laterally-spaced memory blocks individually comprising a vertical stack comprising alternating insulative tiers and conductive tiers. Operative channel-material strings of memory cells extend through the insulative tiers and the conductive tiers. The operative channel-material strings in the laterally-spaced memory blocks comprise part of a memory plane. An elevationally-extending wall is in the memory plane laterally-between immediately-laterally-adjacent of the memory blocks and that completely encircles an island that is laterally-between immediately-laterally-adjacent of the memory blocks in the memory plane. Other embodiments, including method are disclosed.

Abstract: Microelectronic devices include a stack having a vertically alternating sequence of insulative and conductive structures arranged in tiers. Slit structures extend through the stack, dividing the stack into blocks. A first series of stadiums—within the stack of a first block of a pair of the blocks—includes at least one stadium having multiple parallel sets of staircases. A second series of stadiums—within the stack of a second block of the pair of blocks—includes at least one additional stadium having additional multiple parallel sets of staircases that are mirrored, across one of the slit structures, to the multiple parallel sets of staircases of the first series. In methods of fabrication, common mask openings are used to form the mirrored staircase profiles once stadiums are already at substantially their final depths in the stack structure. Electronic systems are also disclosed.

Abstract: Methods, systems, and devices for folded staircase via routing for memory are described. For instance, a memory device may include a set of word lines extending in first direction. Additionally, the memory device may include a first via, a second via, and a third via in a trench that extends through at least a portion of the set of word lines The first via, the second via, and the third via may extend in a second direction different than the first, where the second via is between the first via and the third via along the first direction, and where the second via is coupled with a word line of the set of word lines. Additionally, the first via and the third via may be electrically isolated from the word line of the set of word lines.

Abstract: A microelectronic device includes a stack structure having tiers each including conductive material vertically neighboring insulative material and conductive contact structures. The stack structure is divided into blocks horizontally extending in parallel in a first direction and separated from one another in a second direction orthogonal to the first direction by insulative slot structures. At least one of the blocks includes a lower stadium structure having steps including edges of some of the tiers, and an upper stadium structure vertically overlying the lower stadium structure and having additional steps including edges of some other of the tiers vertically overlying the some of the tiers. The additional steps have greater tread widths in the first direction than the steps. Conductive contact structures are in contact with the additional steps of the upper stadium structure of the at least one of the blocks. Memory devices and electronic systems are also described.

Abstract: Methods, systems, and devices for staircase formation in a memory array are described. A first liner material may be deposited on a tread above a first contact surface and a portion of the first liner material may be doped. A second liner material may be deposited over the first liner and a portion of the second liner material may be doped. After doping the portions of the liner materials, the undoped portions of the liner materials may be removed so that the materials above a second contact surface can be at least partially removed via a first removal process. The doped portion of the first liner material may then be cut back so that a second removal process can expose the second contact surface and a third contact (while the first contact surface is protected from the removal process by the liner materials).

Abstract: A microelectronic device includes a stack structure comprising blocks separated from one another by dielectric slot structures and each including a vertically alternating sequence of conductive structures and insulative structures arranged in tiers. At least one of the blocks comprising a stadium structure comprising opposing staircase structures each having steps comprising edges of the tiers; and a filled trench vertically overlying and within horizontal boundaries of the stadium structure of the at least one of the blocks. The filled trench includes a dielectric liner material on the opposing staircase structures of the stadium structure and on inner sidewalls of the two bridge regions and at least one dielectric structure doped with one or more of carbon and boron on the dielectric liner material, the at least one dielectric structure horizontally overlapping the steps of the stadium structure.

Abstract: Methods, systems, and devices for staircase formation in a memory array are described. A liner composed of a first liner material may be deposited on a tread and a first portion of the liner may be doped. After doping the first portion of the liner, a second portion of the liner may be converted into a second liner material using a chemical process. After converting the second portion of the liner into the second liner material, the first portion of the liner material may be removed so that a subsequent removal process can expose a first sub-tread. After exposing the first sub-tread, the second portion of the liner may be removed so that a second sub-tread is exposed.

Abstract: A microelectronic device comprises a stack structure comprising a vertically alternating sequence of conductive material and insulative material arranged in tiers. The stack structure has blocks separated from one another by first dielectric slot structures. Each of the blocks comprises two crest regions, a stadium structure interposed between the two crest regions in a first horizontal direction and comprising opposing staircase structures each having steps comprising edges of the tiers of the stack structure, and two bridge regions neighboring opposing sides of the stadium structure in a second horizontal direction orthogonal to the first horizontal direction and having upper surfaces substantially coplanar with upper surfaces of the two crest regions. At least one second dielectric slot structure is within horizontal boundaries of the stadium structure in the first horizontal direction and partially vertically extends through and segmenting each of the two bridge regions.

Abstract: An electronic device comprises a stack comprising an alternating sequence of conductive structures and insulative structures arranged in tiers, and at least one dielectric-filled slot extending vertically through the stack and extending in a first horizontal direction. The at least one dielectric-filled slot is defined between two internal sidewalls of the stack. The electronic device comprises additional dielectric-filled slots extending vertically through the stack and extending in a second horizontal direction transverse to the first horizontal direction, and isolation structures laterally interposed between the at least one dielectric-filled slot and the additional dielectric-filled slots. The isolation structures are laterally adjacent to the conductive structures of the stack, and at least some of the isolation structures are vertically adjacent to the insulative structures of the stack. Related systems and methods of forming the electronic devices are also disclosed.

Abstract: A method of forming a microelectronic device comprises forming isolated nitride structures on steps of stair step structures comprising stacked tiers comprising alternating levels of a first insulative material and a second insulative material, forming a photoresist material over some of the stair step structures, and replacing the isolated nitride structures and the second insulative material with an electrically conductive material to respectively form conductive pad structures and electrically conductive lines. Related microelectronic devices and electronic devices are also disclosed.

Abstract: Microelectronic devices include a stack structure having a vertically alternating sequence of insulative structures and conductive structures arranged in tiers. At least one stadium, of stadiums within the stack structure, comprise staircase(s) having steps provided by a group of the conductive structures. Step contacts extend to the steps of the staircase(s) of the at least one of the stadiums. Each conductive structure of the group of conductive structures has more than one of the step contacts in contact therewith at at least one of the steps of the staircase(s). Additional microelectronic devices are also disclosed, as are methods of fabrication and electronic systems.

Abstract: A method used in forming a memory array comprising strings of memory cells comprises forming a lower stack comprising vertically-alternating different-composition lower first tiers and lower second tiers. The lower stack comprises lower channel-material strings extending through the lower first tiers and the lower second tiers. An upper stack is formed directly above the lower stack. The upper stack comprises vertically-alternating different-composition upper first tiers and upper second tiers. The upper stack comprises upper channel-material strings of select-gate transistors. Individual of the upper channel-material strings are directly electrically coupled to individual of the lower channel-material strings. The upper and lower first tiers are conductive at least in a finished-circuitry construction. The upper and lower second tiers are insulative and comprise insulative material.

Abstract: Some embodiments include an integrated assembly having a stack of alternating first and second levels. The first levels contain conductive material and the second levels contain insulative material. At least some of the first and second levels are configured as steps. Each of the steps has one of the second levels over an associated one of the first levels. A layer is over the steps and is spaced from the stack by an intervening insulative region. Insulative material is over the layer. Conductive interconnects extend through the insulative material, through the layer, through the intervening insulative region and to the conductive material within the first levels of the steps. Some embodiments include methods of forming integrated assemblies.

Abstract: A microelectronic device includes a stack structure, a staircase structure, conductive pad structures, and conductive contact structures. The stack structure includes vertically alternating conductive structures and insulating structures arranged in tiers. Each of the tiers individually includes one of the conductive structures and one of the insulating structures. The staircase structure has steps made up of edges of at least some of the tiers of the stack structure. The conductive pad structures are on the steps of the staircase structure and include beta phase tungsten. The conductive contact structures are on the conductive pad structures. Memory devices, electronic systems, and methods of forming microelectronic devices are also described.

Abstract: Memory circuitry comprising strings of memory cells comprises channel-material strings of memory cells extending through insulative tiers and conductive tiers in a memory-array region. The insulative and conductive tiers extend from the memory-array region into a stair-step region. A plurality of stair-step structures is in the stair-step region. The stair-step structures individually comprise two opposing flights of stairs. The stair-step structures comprise an SGD stair-step structure and non-SGD stair-step structures. At least one of the non-SGD stair-step structures has less total stairs than are in individual of multiple others of the non-SGD stair-step structures. Other embodiments, including method, are disclosed.

Abstract: A method used in forming memory circuitry comprises forming a stack comprising vertically-alternating first tiers and second tiers. The stack extends from a memory-array region into a stair-step region. The first tiers are conductive and the second tiers are insulative at least in a finished-circuitry construction. A first layer of imageable resist is exposed to actinic radiation and developed to form a first opening there-through in the stair-step region. The developed first layer is used in a plurality of alternating etching and lateral-trimming steps that widens the first opening and forms two opposing flights of stairs in the stack in the stair-step region. A second layer of imageable resist is formed directly above the two opposing flights of stairs. The second layer is exposed to actinic radiation and developed to form a second opening there-through. The second opening exposes all of the stairs of one of the two opposing flights.

Abstract: A memory array comprising strings of memory cells comprises laterally-spaced memory blocks individually comprising a vertical stack comprising alternating insulative tiers and conductive tiers. Operative channel-material strings of memory cells extend through the insulative tiers and the conductive tiers. The operative channel-material strings in the laterally-spaced memory blocks comprise part of a memory plane. An elevationally-extending wall is in the memory plane laterally-between immediately-laterally-adjacent of the memory blocks and that completely encircles an island that is laterally-between immediately-laterally-adjacent of the memory blocks in the memory plane. Other embodiments, including method are disclosed.