Methods used in forming a memory array comprising strings of memory cells and memory arrays comprising strings of memory cells
A method used in forming a memory array comprising strings of memory cells comprises forming memory blocks individually comprising a vertical stack comprising alternating insulative tiers and conductive tiers. Individual of the conductive tiers comprise laterally-outer edges comprising conductive molybdenum-containing metal material extending horizontally-along its memory block. Channel-material strings extend through the insulative tiers and the conductive tiers. At least one of conductive or semiconductive material is formed extending horizontally-along the memory blocks laterally-outward of the laterally-outer edges comprising the conductive molybdenum-containing metal material that extends horizontally-along its memory block. Insulator material extending horizontally-along the memory blocks is formed laterally-outward of the at least one of the conductive or the semiconductive material that is laterally-outward of the laterally-outer edges comprising the conductive molybdenum-containing metal material. Other embodiments, including structure independent of method, are disclosed.
1 . A method used in forming a memory array comprising strings of memory cells, comprising:
forming memory blocks individually comprising a vertical stack comprising alternating insulative tiers and conductive tiers, individual of the conductive tiers comprising laterally-outer edges comprising conductive molybdenum-containing metal material extending horizontally-along its memory block, channel-material strings extending through the insulative tiers and the conductive tiers;
forming at least one of conductive or semiconductive material extending horizontally-along the memory blocks laterally-outward of the laterally-outer edges comprising the conductive molybdenum-containing metal material that extends horizontally-along its memory block; and
forming insulator material extending horizontally-along the memory blocks laterally-outward of the at least one of the conductive or the semiconductive material that is laterally-outward of the laterally-outer edges comprising the conductive molybdenum-containing metal material.
2 . The method of claim 1 wherein the insulator material comprises silicon nitride.
3 . The method of claim 1 wherein the conductive molybdenum-containing metal material consists essentially of elemental molybdenum.
4 . The method of claim 1 wherein the at least one of the conductive or the semiconductive material is directly against the molybdenum-containing metal material and the insulator material is directly against the at least one of the conductive or the semiconductive material.
5 . The method of claim 1 wherein the at least one of the conductive or the semiconductive material comprises the conductive material.
6 . The method of claim 5 wherein the conductive material comprises at least one of W, WN, WO x , WO x N y , Ti, TiN, Co, CoN, Ru, RuN, and conductively-doped polysilicon.
7 . The method of claim 1 wherein the at least one of the conductive or the semiconductive material comprises the semiconductive material.
8 . The method of claim 7 wherein the semiconductive material comprises at least one of AlN and semiconductively-doped polysilicon.
9 . The method of claim 1 wherein the at least one of the conductive or the semiconductive material comprises a metal nitride, the forming of the metal nitride comprising:
depositing the metal of the metal nitride horizontally-along the memory blocks laterally-outward of the laterally-outer edges comprising the conductive molybdenum-containing metal material that extends horizontally-along its memory block; and
exposing the deposited metal to nitrogen to form the metal nitride from the nitrogen and the deposited metal.
10 . The method of claim 1 wherein the at least one of the conductive or the semiconductive material is not laterally-outward of laterally-outer edges of insulative material of the insulative tiers.
11 . The method of claim 1 wherein the insulator material is laterally-outward of laterally-outer edges of insulative material of the insulative tiers.
12 . The method of claim 11 wherein the at least one of the conductive or the semiconductive material is not laterally-outward of the laterally-outer edges of the insulative material of the insulative tiers.
13 . The method of claim 1 wherein the forming of the at least one of the conductive or the semiconductive material is conducted selectively directly against the conductive molybdenum-containing metal material relative to laterally-outer edges of insulative material of the insulative tiers.
14 . A method used in forming a memory array comprising strings of memory cells, comprising:
forming memory blocks individually comprising a vertical stack comprising alternating insulative tiers and conductive tiers, individual of the conductive tiers comprising laterally-outer edges comprising conductive molybdenum-containing metal material extending horizontally-along its memory block and that are laterally-recessed from laterally-outer edges of insulative material in the insulative tiers, channel-material strings extending through the insulative tiers and the conductive tiers;
forming at least one of conductive or semiconductive material extending horizontally-along the memory blocks laterally-outward of the laterally-outer edges comprising the conductive molybdenum-containing metal material that extends horizontally-along its memory block, the at least one of the conductive or the semiconductive material being laterally-recessed from the laterally-outer edges of the insulative material in the insulative tiers to leave lateral recesses in the conductive tiers relative to the laterally-outer edges of the insulative material in the insulative tiers; and
forming insulator material extending horizontally-along the memory blocks in the lateral recesses laterally-outward of the at least one of the conductive or the semiconductive material and laterally-outward of the laterally-outer edges of the insulative material in the insulative tiers.
15 . The method of claim 14 wherein the insulator material comprises silicon nitride.
16 . The method of claim 14 wherein the forming of the at least one of the conductive or the semiconductive material is conducted selectively directly against the conductive molybdenum-containing metal material relative to laterally-outer edges of insulative material in the insulative tiers.
17 . The method of claim 14 wherein the at least one of the conductive or the semiconductive material comprises a metal nitride, the forming of the metal nitride comprising:
depositing the metal of the metal nitride horizontally-along the memory blocks laterally-outward of the laterally-outer edges comprising the conductive molybdenum-containing metal material that extends horizontally-along its memory block; and
exposing the deposited metal to nitrogen to form the metal nitride from the nitrogen and the deposited metal.
18 . A method used in forming a memory array comprising strings of memory cells, comprising:
forming memory blocks individually comprising a vertical stack comprising alternating insulative tiers and conductive tiers, individual of the conductive tiers comprising laterally-outer edges comprising conductive molybdenum-containing metal material extending horizontally-along its memory block, channel-material strings extending through the insulative tiers and the conductive tiers;
forming silicon nitride extending horizontally-along the memory blocks laterally-outward of the laterally-outer edges comprising the conductive molybdenum-containing metal material that extends horizontally-along its memory block, the forming of the silicon nitride comprising:
depositing silicon horizontally-along the memory blocks laterally-outward of the laterally-outer edges comprising the conductive molybdenum-containing metal material that extends horizontally-along its memory block; and
exposing the deposited silicon to nitrogen to form the silicon nitride from the nitrogen and the deposited silicon, the silicon nitride so-formed having greater silicon concentration adjacent the molybdenum-containing metal material than distal there-from;
forming insulator material extending horizontally-along the memory blocks laterally-outward of the silicon nitride that is laterally-outward of the laterally-outer edges comprising the conductive molybdenum-containing metal material.
19 . The method of claim 18 wherein the insulator material comprises stoichiometric silicon nitride.
20 . The method of claim 18 wherein,
the laterally-outer edges comprising the conductive molybdenum-containing metal material are laterally-recessed from laterally-outer edges of insulative material in the insulative tiers;
the at least one of the conductive or the semiconductive material is laterally-recessed from laterally-outer edges of the insulative material in the insulative tiers to leave lateral recesses in the conductive tiers relative to the laterally-outer edges of the insulative material in the insulative tiers; and
forming the insulator material in the lateral recesses and laterally-outward of the laterally-outer edges of the insulative material in the insulative tiers.
21 . The method of claim 18 wherein the silicon nitride so-formed comprises at least a portion thereof that is stoichiometric.
22 . The method of claim 18 wherein the silicon nitride so-formed does not comprise any portion thereof that is stoichiometric.