Integrated circuitry, memory arrays comprising strings of memory cells, methods used in forming integrated circuitry, and methods used in forming a memory array comprising strings of memory cells
A method used in forming a memory array comprises forming a stack comprising vertically-alternating insulative tiers and conductive tiers. Channel-material strings of memory-cell strings extend through the insulative and conductive tiers. Conductive vias are formed above and individually directly electrically coupled to individual of the channel-material strings. Digitlines are formed above and are individually directly electrically coupled to a plurality of individual of the conductive vias there-below. The forming of the digitlines comprises forming lower elemental-form tungsten directly against tops of the individual conductive vias. The lower elemental-form tungsten is exposed to oxygen-containing gas or plasma to form WO x , where “x” is greater than 0 and no more than 3.0. The WO x has a maximum thickness greater than 0 and no more than 30 Angstroms in a finished construction. Upper elemental-form tungsten is physical vapor deposited directly against the WO x . Other embodiments, including structure, are disclosed.
1 . A method used in forming a memory array, comprising:
forming a stack comprising vertically-alternating insulative tiers and conductive tiers, channel-material strings of memory-cell strings extending through the insulative and conductive tiers;
forming conductive vias above and individually directly electrically coupled to individual of the channel-material strings;
forming digitlines above and that are individually directly electrically coupled to a plurality of individual of the conductive vias there-below, the forming of the digitlines comprising:
forming lower elemental-form tungsten directly against tops of the individual conductive vias;
exposing the lower elemental-form tungsten to oxygen-containing gas or plasma to form WO x , where “x” is greater than 0 and no more than 3.0, the WO x having a maximum thickness greater than 0 and no more than 30 Angstroms in a finished construction; and
physical vapor depositing upper elemental-form tungsten directly against the WO x .
2 . The method of claim 1 wherein the lower elemental-form tungsten is formed by physical vapor deposition.
3 . The method of claim 1 wherein the lower elemental-form tungsten has a maximum thickness of no greater than 30 Angstroms in the finished construction.
4 . The method of claim 3 wherein the maximum thickness of the lower elemental-form tungsten is no less than 15 Angstroms in the finished construction.
5 . The method of claim 4 wherein the lower elemental-form tungsten is formed by physical vapor deposition.
6 . The method of claim 1 wherein the upper elemental-form tungsten is thicker than the lower elemental-form tungsten in the finished construction.
7 . The method of claim 6 wherein the upper elemental-form tungsten has a maximum thickness of at least 150 Angstroms in the finished construction.
8 . The method of claim 7 wherein the upper elemental-form tungsten has a maximum thickness of no more than 1,000 Angstroms in the finished construction.
9 . The method of claim 1 wherein the lower elemental-form tungsten, the WO x , and the upper elemental-form tungsten are collectively subtractively-patterned using a mask and etching to form individual of the digitlines.
10 . The method of claim 9 comprising forming insulative material directly above the upper elemental-form tungsten that is subtractively-patterned with the collective subtractively-patterning of the lower elemental-form tungsten, the WO x , and the upper elemental-form tungsten.
11 . The method of claim 1 wherein the WO x has at least two different vertical portions thereof having different W content relative one another.
12 . The method of claim 11 wherein the W content is greatest in an uppermost part of the WO x .
13 . The method of claim 1 comprising forming a void-space longitudinally-along and laterally-between immediately-laterally-adjacent of the digitlines, the void-space having a top that is above tops of its immediately-laterally-adjacent digitlines, the void-space having a bottom that is below bottoms of its immediately-laterally-adjacent digitlines.
14 . A method used in forming integrated circuitry, comprising:
forming a conductive via;
forming a horizontally-elongated conductive line directly above and directly against the conductive via, the forming of the conductive line comprising:
forming lower elemental-form tungsten directly against a top of the conductive via;
exposing the lower elemental-form tungsten to oxygen-containing gas or plasma to form WO x , where “x” is greater than 0 and no more than 3.0, the WO x having a maximum thickness greater than 0 and no more than 30 Angstroms in a finished construction; and
physical vapor depositing upper elemental-form tungsten directly against the WO x .
15 . The method of claim 14 wherein the lower elemental-form tungsten is formed by physical vapor deposition.
16 . The method of claim 14 wherein the lower elemental-form tungsten has a maximum thickness of no greater than 30 Angstroms in the finished construction.
17 . The method of claim 16 wherein the maximum thickness of the lower elemental-form tungsten is no less than 15 Angstroms in the finished construction.
18 . The method of claim 17 wherein the lower elemental-form tungsten is formed by physical vapor deposition.
19 . The method of claim 14 wherein the upper elemental-form tungsten is thicker than the lower elemental-form tungsten in the finished construction.
20 . The method of claim 19 wherein the upper elemental-form tungsten has a maximum thickness of at least 150 Angstroms in the finished construction.
21 . The method of claim 20 wherein the upper elemental-form tungsten has a maximum thickness of no more than 1,000 Angstroms in the finished construction.
22 . The method of claim 14 wherein the lower elemental-form tungsten, the WO x , and the upper elemental-form tungsten are collectively subtractively-patterned using a mask and etching to form individual of the digitlines.
23 . The method of claim 22 comprising forming insulative material directly above the upper elemental-form tungsten that is subtractively-patterned with the collective subtractively-patterning of the lower elemental-form tungsten, the WO x , and the upper elemental-form tungsten.
24 . The method of claim 14 wherein the WO x has at least two different vertical portions thereof having different W content relative one another.
25 . The method of claim 24 wherein the W content is greatest in an uppermost part of the WO x .
26 . The method of claim 14 comprising forming a void-space longitudinally-along and laterally-between immediately-laterally-adjacent of the digitlines, the void-space having a top that is above tops of its immediately-laterally-adjacent digitlines, the void-space having a bottom that is below bottoms of its immediately-laterally-adjacent digitlines.