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: 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: Integrated circuitry comprising a memory array comprises strings of memory cells comprising laterally-spaced memory blocks individually comprising a first vertical stack comprising alternating insulative tiers and conductive tiers. Strings of memory cells comprise channel-material strings that extend through the insulative tiers and the conductive tiers. The conductive tiers individually comprise a horizontally-elongated conductive line. A second vertical stack is aside the first vertical stack. The second vertical stack comprises an tipper portion and a lower portion. The upper portion comprises vertically alternating first tiers and second insulating tiers that are of different composition relative one another. The lower portion comprises an upper polysilicon-comprising layer, a lower polysilicon-comprising layer, an intervening-material layer vertically between the tipper and lower polysilicon-comprising layers.

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: 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. Channel-material-string structures of memory cells extend through the insulative tiers and the conductive tiers. The channel-material-string structures individually comprise an upper portion above and joined with a lower portion. Individual of the channel-material-string structures comprise at least one external jog surface in a vertical cross-section where the upper and lower portions join. Other embodiments, including method are disclosed.

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. A channel-material string is in individual channel openings in the vertically-alternating first tiers and second tiers. A conductor-material contact is in the individual channel openings directly against the channel material of individual of the channel-material strings. The conductor-material contacts are vertically recessed in the individual channel openings. A conductive via is formed in the individual channel openings directly against the vertically-recessed conductor-material contact in that individual channel opening. Other aspects, including structure independent of method, are disclosed.

Abstract: An electronic device comprising a source stack comprising one or more conductive materials, and an oxide fill region within an upper portion of the source stack. A source contact is adjacent to the source stack and the oxide fill region, and a doped semiconductive material is adjacent to the source contact. Tiers of alternating conductive materials and dielectric materials are adjacent to the doped semiconductive material, and pillars extend 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: Electronic devices comprising a source stack comprising one or more conductive materials, a source contact adjacent to the source stack, tiers of alternating conductive materials and insulative materials adjacent to the source contact, pillars extending through the tiers and the source contact and into the source stack, a slit structure extending through the tiers and the source contact, and an implant structure extending within the slit structure and into the source stack. Related methods and systems are also disclosed.

Abstract: Some embodiments include a NAND memory array having a vertical stack of alternating insulative levels and conductive levels. The conductive levels include control gate regions. High-k dielectric material is adjacent to the control gate regions and is configured as an arrangement of first vertically-extending linear segments which are vertically spaced from one another. Charge-blocking material is adjacent to the high-k dielectric material and is configured as an arrangement of second vertically-extending linear segments which are vertically spaced from one another. Charge-storage material is adjacent to the charge-blocking material and is configured as an arrangement of third vertically-extending linear segments which are vertically spaced from one another. Gate-dielectric material is adjacent to the charge-storage material. Channel material extends vertically along the stack and is adjacent to the gate-dielectric material.

Abstract: Some embodiments include an integrated assembly having a first deck which has first memory cells, and having a second deck which has second memory cells. The first memory cells have first control gate regions which include a first conductive material vertically between horizontally-extending bars of a second conductive material. The second memory cells have second control gate regions which include a fourth conductive material along an outer surface of a third conductive material. A pillar passes through the first and second decks. The pillar includes a dielectric-barrier material laterally surrounding a channel material. The first and fourth materials are directly against the dielectric-barrier material. Some embodiments include methods of forming integrated assemblies.

Abstract: A method used in forming a memory array comprising strings of memory cells comprises forming an upper stack directly above a lower stack. The lower stack comprises vertically-alternating lower-first-tiers and lower-second-tiers. The upper stack comprises vertically-alternating upper-first-tiers and upper-second-tiers. Lower channel openings extend through the lower-first-tiers and the lowers-second-tiers. The lower channel openings have sacrificial material therein. An upper of the lower-first-tiers or a lower of the upper-first-tiers comprises non-stoichiometric silicon nitride comprising (a) or (b), where (a): a nitrogen-to-silicon atomic ratio greater than 1.33 and less than 1.5; and (b): a nitrogen-to-silicon atomic ratio greater than or equal to 1.0 and less than 1.33. A higher of the upper-first-tiers that is above said lower upper-first-tier comprises silicon nitride not having either the (a) or the (b).

Abstract: A method used in forming a memory array comprising strings of memory cells comprises forming a conductor tier comprising conductor material on a substrate. Laterally-spaced memory-block regions are formed that individually comprise a vertical stack comprising alternating first tiers and second tiers directly above the conductor tier. Channel-material strings of memory cells extend through the first tiers and the second tiers. Horizontally-elongated lines are formed in the conductor tier between the laterally-spaced memory-block regions. The horizontally-elongated lines are of different composition from an upper portion of the conductor material and comprise metal material. After the horizontally-elongated lines are formed, conductive material is formed in a lower of the first tiers and that directly electrically couples together the channel material of individual of the channel-material strings and the conductor material of the conductor tier.

Abstract: A method used in forming a memory array comprising strings of memory cells comprises forming a conductor tier comprising conductor material on a substrate. Laterally-spaced memory-block regions individually comprising a vertical stack comprising alternating first tiers and second tiers are formed directly above the conductor tier. Channel-material strings extend through the first tiers and the second tier. Conducting material is formed in a lower of the first tiers that directly electrically couples together the channel material of individual of the channel-material strings and the conductor material of the conductor tier. The forming of the conducting material comprises forming conductive material in the lower first tier against the channel material of the individual channel-material strings. The conductive material comprises an upper portion and a lower portion having a void-space vertically there-between. The void-space comprises an exposed silicon-containing surface.

Abstract: A microelectronic device comprises a stack structure, a memory pillar, and a boron-containing material. The stack structure comprises alternating conductive structures and dielectric structures. The memory pillar extends through the stack structure and defines memory cells at intersections of the memory pillar and the conductive structures. The boron-containing material is on at least a portion of the conductive structures of the stack structure. Related methods and electronic systems are also described.

Abstract: A method used in forming a memory array comprising strings of memory cells comprises forming memory block regions individually comprising a vertical stack comprising alternating insulative tiers and conductive tiers. Channel-material strings extend through the insulative tiers and the conductive tiers. The conductive tiers individually comprise a void-space extending laterally-across individual of the memory-block regions. At least one of conductive or semiconductive material is formed in the void-space laterally-outward of individual of the channel-material strings. Conductive molybdenum-containing metal material is formed in the void-space directly against the at least one of the conductive or the semiconductive material and a conductive line comprising the conductive molybdenum-containing metal material is formed therefrom. The at least one of the conductive or the semiconductive material is of different composition from that of the conductive molybdenum-containing metal material.

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 memory array comprising strings of memory cells comprises laterally-spaced memory blocks individually comprising a first vertical stack comprising vertically-alternating insulative tiers and conductive tiers. Strings of memory cells comprise channel-material strings that extend through the insulative tiers and the conductive tiers. A second vertical stack is aside the first vertical stack. The second vertical stack comprises insulative tiers collectively comprising at least two different compositions relative individual of the insulative tiers. Individual of the at least two different compositions comprise silicon nitride. One of the individual different compositions comprise carbon-doped silicon nitride having at least 0.5 atomic percent more carbon than atomic percent of carbon, if any, in the silicon nitride of another of the individual different compositions. Other embodiments, including method, are disclosed.

Abstract: A memory array comprising strings of memory cells comprises laterally-spaced memory blocks individually comprising a first vertical stack comprising vertically-alternating insulative tiers and conductive tiers. Strings of memory cells comprise channel-material strings that extend through the insulative tiers and the conductive tiers. A second vertical stack is aside the first vertical stack. The second vertical stack comprises an upper portion directly above a lower portion. The upper portion comprises vertically-alternating tiers that are of different composition relative one another. The lower portion comprises dummy plugs that comprise metal oxide directly above metal material. The metal oxide and the metal material comprise different compositions relative one another. Other embodiments, including method, are disclosed.

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 lowest of the conductive tiers directly electrically couples together the channel material of individual of the channel-material strings and the conductor material of the conductor tier. An uppermost portion of the conductor material comprises conductively-doped semiconductive material that is directly against the conducting material, of different composition from that of the conducting material, and comprises at least one of carbon, nitrogen, oxygen, metal, and n-type conductively-doped semiconductive material also comprising boron. Other embodiments, including method, are disclosed.

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. The stack comprises laterally-spaced memory-block regions and a through-array-via (TAV) region. The stack comprises channel-material strings extending through the first tiers and the second tiers. The stack comprises horizontally-elongated trenches extending through the first tiers and the second tiers and that are individually between immediately-laterally-adjacent of the memory-block regions. The stack comprises TAV openings in the TAV region. Conductive material is formed in the TAV openings and in the horizontally-elongated trenches at the same time. All of the conductive material is removed from the horizontally-elongated trenches while leaving the conductive material in the TAV openings to comprise TAVs therein in a finished circuitry construction. After the removing, intervening material is formed in the horizontally-elongated trenches.