CPC H10B 43/27 (2023.02) [H10B 41/10 (2023.02); H10B 41/27 (2023.02); H10B 43/10 (2023.02)] | 22 Claims |
1. A method used in forming a memory array comprising strings of memory cells, comprising:
forming a lower portion of a stack that will comprise vertically-alternating first tiers and second tiers, the stack comprising laterally-spaced memory-block regions, material of the first tiers being of different composition from material of the second tiers, a lowest of the first tiers comprising first sacrificial material;
forming horizontally-elongated lines in a next-lowest first tier that are individually between immediately-laterally-adjacent of the memory-block regions; the lines comprising second sacrificial material;
forming the vertically-alternating first tiers and second tiers of an upper portion of the stack above the lower portion and the lines,
forming channel-material-string structures that extend through first tiers and the second tiers in the upper portion to the lowest first tier in the lower portion;
forming horizontally-elongated trenches into the stack that are individually between the immediately-laterally-adjacent memory-block regions and extend to the line there-between;
removing the second sacrificial material of the lines through the trenches; and
forming intervening material in the trenches and void-spaces left as a result of the removing of the second sacrificial material of the lines.
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