US 12,302,766 B2
Sparse piers for three-dimensional memory arrays
Stephen W. Russell, Boise, ID (US); Enrico Varesi, Milan (IT); David H. Wells, Boise, ID (US); Paolo Fantini, Vimercate (IT); and Lorenzo Fratin, Buccinasco (IT)
Assigned to Micron Technology, Inc., Boise, ID (US)
Filed by Micron Technology, Inc., Boise, ID (US)
Filed on Mar. 24, 2022, as Appl. No. 17/656,280.
Prior Publication US 2023/0309426 A1, Sep. 28, 2023
Int. Cl. H10B 63/10 (2023.01); G11C 13/00 (2006.01); H10B 63/00 (2023.01); H10D 64/01 (2025.01); H10N 70/00 (2023.01); H01L 21/02 (2006.01)
CPC H10N 70/826 (2023.02) [G11C 13/0028 (2013.01); H10B 63/84 (2023.02); H10D 64/017 (2025.01); H10N 70/021 (2023.02); H10N 70/841 (2023.02); H10N 70/882 (2023.02); G11C 13/003 (2013.01); G11C 2213/71 (2013.01); G11C 2213/78 (2013.01); H01L 21/02507 (2013.01); H10B 63/10 (2023.02); H10B 63/845 (2023.02)] 12 Claims
OG exemplary drawing
 
1. A method, comprising:
depositing a stack of layers over a substrate, the stack of layers comprising alternating layers of a first material and a second material, wherein the first material comprises a first dielectric material;
forming a plurality of piers through the stack of layers based at least in part on forming a plurality of first cavities through the stack of layers and depositing a third material in the plurality of first cavities, wherein the third material comprises a second dielectric material;
forming an interleaved pair of comb structures comprising a first comb structure and a second comb structure based at least in part on forming a plurality of second cavities through the stack of layers, wherein, for both the first comb structure and the second comb structure, each of the layers of the first material and each of the layers of the second material is in contact with each pier of the plurality of piers;
forming a plurality of first voids between the layers of the first material of the first comb structure and a plurality of second voids between the layers of the first material of the second comb structure based at least in part on removing the second material of the first comb structure and the second comb structure;
forming a plurality of first word lines and a plurality of second word lines based at least in part on depositing a conductive material in the plurality of first voids and in the plurality of second voids, respectively;
forming a plurality of pillars in the plurality of second cavities based at least in part on depositing a second conductive material in the plurality of second cavities; and
forming a plurality of memory cells based at least in part on depositing a memory material in the plurality of first voids and in the plurality of second voids, wherein each memory cell of the plurality of memory cells is electrically coupled between a pillar of the plurality of pillars and a word line of the plurality of first word lines or the plurality of second word lines.