Abstract: A microelectronic device comprises a stack structure, a staircase structure, a first liner material, a liner structure, conductive contact structures, and barrier structures. The stack structure comprises vertically alternating conductive structures and insulative structures arranged in tiers. Each of the tiers individually comprises one of the conductive structures and one of the insulative structures. The staircase structure has steps comprising edges of at least some of the tiers of the stack structure. The first liner material is on the steps of the staircase structure, and the liner structure on the first liner material. The conductive contact structures extend through the first liner material and the liner structure and to the conductive structures of the stack structure. The barrier structures are between the conductive contact structures and the liner structure vertically span substantially the same tiers of the stack structure as the liner structure.

Abstract: Electronic devices comprising a doped dielectric material adjacent to a source contact, tiers of alternating conductive materials and dielectric materials adjacent to the doped dielectric material, and pillars extending through the tiers, the doped dielectric material, and the source contact and into the source stack. Related methods and electronic systems are also disclosed.

Abstract: Methods, systems, and devices for access circuitry structures for three-dimensional (3D) memory arrays are described. A memory device may include levels of memory cells over a substrate. To support accessing memory cells at respective levels, the memory device may include a conductive pillar extending through the levels of memory cells and coupled with one or more memory cells at respective levels of memory cells. The memory device may include a bit line and a contact that is configured to couple the bit line with the conductive pillar. The conductive pillar may be formed such that it extends into a portion of the contact, and a contact resistance between the conductive pillar and the bit line may be based on the conductive pillar extending into the portion of the contact.

Abstract: Microelectronic devices include a region with a tiered stack that includes insulative, conductive, and non-conductive structures arranged in tiers. The insulative structures vertically alternate with both the conductive and the non-conductive structures. Each of the conductive structures is vertically spaced from another of the conductive structures by at least one of the non-conductive structures and at least two of the insulative structures. A composition of the non-conductive structures differs from a composition of the insulative structures. In methods of fabrication, a precursor stack is formed to include the insulative structures vertically alternating with first and second non-conductive structures. In a region of the precursor stack, the first non-conductive structures are removed, forming voids between multi-structure tier groups. Conductive structures are formed in the voids. Electronic systems are also 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 stair-step region comprises a cavity comprising a flight of stairs. The first tiers are conductive and the second tiers are insulative at least in a finished-circuitry construction. A lining is formed in and that less-than-fills the cavity atop treads of the stairs. Individual of the treads comprise conducting material of one of the first tiers in the finished-circuitry construction. The lining that is atop the treads is replaced with at least one of metal material, polysilicon, or SiGe and insulative material is provided in remaining volume of the cavity directly above the at least one of the metal material, the polysilicon, or the SiGe. Conductive vias are formed through the insulative material and the at least one of the metal material, the polysilicon, or the SiGe.

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: Electronic devices comprising a source stack comprising one or more conductive materials, a source implant region within a top portion of the source stack, a source contact adjacent to the source stack, sidewalls of the source contact vertically adjacent to the source implant region, a doped semiconductive material adjacent to a source contact, tiers of alternating conductive materials and dielectric materials adjacent to the doped semiconductive material, and pillars extending through the tiers, the doped semiconductive material, and the source contact and into the source stack. Additional electronic devices are also disclosed, as are related methods and electronic systems.

Abstract: Methods, systems, and devices for staircase structures for accessing three-dimensional (3D) memory arrays are described. A memory system may include an access region (e.g., a staircase region) that includes circuitry for accessing memory cells at respective levels of memory cells. The access region may include a channel through which a conductive pillar may couple a word line at a level of memory cells with decoder circuitry. During manufacture of the memory system, a channel material may be formed in the channel and etched to form a corner portion in the channel. During a partitioning of the channel, a nitride material over the corner portion may be etched and some of the corner portion may remain in the channel, which may prevent formation of a trench that may cause the conductive pillar to be uncoupled from the word line.

Abstract: A method used in forming a memory array comprising strings of memory cells comprises forming a stack comprising vertically-alternating first tiers and second tiers above a substrate. Horizontally-elongated trenches are formed into the stack to form laterally-spaced memory-block regions. Catalytic material is formed in a bottom region of individual of the trenches. Metal material is electrolessly deposited onto a catalytic surface of the catalytic material to individually fill at least a majority of remaining volume of the individual trenches. Channel-material strings are formed and extend through the first tiers and the second tiers. Other embodiments, including structure independent of method, are disclosed.

Abstract: A method used in forming memory circuitry comprises forming a stack comprising vertically-alternating first tiers and second tiers, with the stack extending from a memory-array region into a stair-step region. The stair-step region comprises a flight of stairs in a first vertical cross-section along a first direction. Masking material is formed directly above the flight of stairs. A species is ion implanted into the masking material to form different-composition first and second regions that are directly above individual of the stairs along a second direction that is orthogonal to the first direction. One of the first and the second regions is removed selectively relative to the other of the first and the second regions.

Abstract: A memory array comprising strings of memory cells comprises a conductor tier comprising conductor material. Laterally-spaced memory blocks individually comprise a vertical stack comprising alternating insulative tiers and conductive tiers. Channel-material strings of memory cells extend through the insulative tiers and the conductive tiers. Conducting material of a lower of the conductive tiers directly electrically coupling together the channel material of individual of the channel-material strings and the conductor material of the conductor tier. The conducting material in the lower conductive tier comprises upper conductively-doped semiconductive material, lower conductively-doped semiconductive material, and intermediate material vertically there-between.

Abstract: A microelectronic device may include a source structure and a stack structure. The stack structure may include a vertically alternating sequence of insulative structures and conductive structures. Filled slits may extend through the stack structure and into the source structure, the slits dividing the stack structure into multiple blocks. Memory cell pillars may extend through the stack structure and into the source structure, the memory cell pillars and the filled slits terminated at substantially the same depth within the source structure as one another.

Abstract: A method used in forming a memory array comprising strings of memory cells comprises forming a stack comprising vertically-alternating different-composition first tiers and second tiers. The stack comprises lower channel-material strings extending through the first tiers and the second tiers. A sacrificial plug comprises sacrificial material directly above individual of the lower channel-material strings. The sacrificial material is removed from laterally-opposing corner regions of the sacrificial plug in a greater amount diagonally than orthogonally relative to a sidewall of individual of the corner regions and than orthogonally relative to a top of the individual corner regions. Insulator material is formed in void spaces left from the removing. After forming the insulator material, remaining volume of the sacrificial plug is removed.

Abstract: A method used in forming a memory array comprises forming a substrate comprising a conductor tier comprising an upper conductor material and a lower conductor material, and a stack comprising vertically-alternating first tiers and second tiers above the conductor tier. Horizontally-elongated trenches are formed through the stack to the upper conductor material and the lower conductor material. At least one of the upper and lower conductor materials have an exposed catalytic surface in the trenches. Metal material is electrolessly deposited onto the catalytic surface to cover the upper conductor material and the lower conductor material within the trenches. Channel-material strings of memory cells are formed and extend through the second tiers and the first tiers. Other embodiments, including structure independent of method, are disclosed.

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 directly above conductor material of a conductor tier. Channel-material-string constructions extend through the insulative and conductive tiers to a lowest of the conductive tiers. The channel-material-string constructions individually comprise a charge-blocking-material string, a storage-material string laterally-inward of the charge-blocking-material string, a charge-passage-material string laterally-inward of the storage-material string, and a channel-material string laterally-inward of the charge-passage-material string. A lowest surface of the charge-blocking-material string that is above a lowest surface of the lowest conductive tier is below a lowest surface of a lowest of the insulative tiers that is immediately-above the lowest conductive tier.

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 directly above conductor material of a conductor tier. Channel-material-string constructions extend through the insulative and conductive tiers to a lowest of the conductive tiers. The channel-material-string constructions individually comprise a charge-blocking-material string, a storage-material string laterally-inward of the charge-blocking-material string, a charge-passage-material string laterally-inward of the storage-material string, and a channel-material string laterally-inward of the charge-passage-material string. Conductive material in the lowest conductive tier directly electrically couples together the channel material of individual of the channel-material strings and the conductor material of the conductor tier.

Abstract: Some embodiments include an integrated structure having a stack of memory cell levels. A pair of channel-material-pillars extend through the stack. A source structure is under the stack. The source structure includes a portion having an upper region, a lower region, and an intermediate region between the upper and lower regions. The upper and lower regions have a same composition and join to one another at edge locations. The intermediate region has a different composition than the upper and lower regions. The edge locations are directly against the channel material of the channel-material-pillars. Some embodiments include methods of forming an integrated assembly.

Abstract: A method used in forming a memory array comprises forming a substrate comprising a conductor tier comprising an upper conductor material and a lower conductor material, and a stack comprising vertically-alternating first tiers and second tiers above the conductor tier. Horizontally-elongated trenches are formed through the stack to the upper conductor material and the lower conductor material. At least one of the upper and lower conductor materials have an exposed catalytic surface in the trenches. Metal material is electrolessly deposited onto the catalytic surface to cover the upper conductor material and the lower conductor material within the trenches. Channel-material strings of memory cells are formed and extend through the second tiers and the first tiers. Other embodiments, including structure independent of method, are disclosed.

Abstract: A microelectronic device may include a source structure and a stack structure. The stack structure may include a vertically alternating sequence of insulative structures and conductive structures. Filled slits may extend through the stack structure and into the source structure, the slits dividing the stack structure into multiple blocks. Memory cell pillars may extend through the stack structure and into the source structure, the memory cell pillars and the filled slits terminated at substantially the same depth within the source structure as one another.

Abstract: Some embodiments include an integrated structure having a stack of memory cell levels. A pair of channel-material-pillars extend through the stack. A source structure is under the stack. The source structure includes a portion having an upper region, a lower region, and an intermediate region between the upper and lower regions. The upper and lower regions have a same composition and join to one another at edge locations. The intermediate region has a different composition than the upper and lower regions. The edge locations are directly against the channel material of the channel-material-pillars. Some embodiments include methods of forming an integrated assembly.