US 12,347,492 B2
Three-dimensional memory device with high contact via density and methods of forming the same
Hirofumi Tokita, Yokkaichi (JP); Tomohiro Kubo, Yokkaichi (JP); Shiqian Shao, Fremont, CA (US); and Fumiaki Toyama, Cupertino, CA (US)
Assigned to Sandisk Technologies, Inc., Milpitas, CA (US)
Filed by SANDISK TECHNOLOGIES LLC, Addison, TX (US)
Filed on Jun. 30, 2022, as Appl. No. 17/810,097.
Prior Publication US 2024/0005990 A1, Jan. 4, 2024
Int. Cl. G11C 16/04 (2006.01); H01L 23/522 (2006.01); H01L 23/528 (2006.01); H10B 41/10 (2023.01); H10B 41/27 (2023.01); H10B 41/35 (2023.01); H10B 43/10 (2023.01); H10B 43/27 (2023.01); H10B 43/35 (2023.01)
CPC G11C 16/0483 (2013.01) [H01L 23/5226 (2013.01); H01L 23/5283 (2013.01); H10B 41/10 (2023.02); H10B 41/27 (2023.02); H10B 41/35 (2023.02); H10B 43/10 (2023.02); H10B 43/27 (2023.02); H10B 43/35 (2023.02)] 23 Claims
OG exemplary drawing
 
1. A three-dimensional memory device, comprising:
an alternating stack of insulating layers and electrically conductive layers;
a first three-dimensional memory array located in a first memory array region; and
a second three-dimensional memory array located in a second memory array region that is laterally spaced from the first memory array region along a first horizontal direction by an inter-array region, wherein the electrically conductive layers comprise common word lines for the first three-dimensional memory array and for the second three-dimensional memory array,
wherein:
the alternating stack is laterally bounded by two trench fill structures that are laterally space apart along a second horizontal direction by an inter-trench spacing;
the electrically conductive layers continuously extend between the first memory array region and the second memory array region and comprise a respective bridge region that is located in the inter-array region and having a width along the second horizontal direction that is less than the inter-trench spacing;
the inter-array region comprises a stepped surface region comprising first vertically-extending surface segments of the alternating stack that are perpendicular to the first horizontal direction and second vertically-extending surface segments of the alternating stack that are perpendicular to the second horizontal direction; and
a first plurality of second vertically-extending surface segments is laterally offset from one of the trench fill structures by a same lateral spacing.