US 12,267,998 B2
Three-dimensional memory device including discrete charge storage elements and methods of forming the same
Rahul Sharangpani, Fremont, CA (US); Raghuveer S. Makala, Campbell, CA (US); Kartik Sondhi, Milpitas, CA (US); Ramy Nashed Bassely Said, San Jose, CA (US); and Senaka Kanakamedala, San Jose, CA (US)
Assigned to Sandisk Technologies, Inc., Milpitas, CA (US)
Filed by SANDISK TECHNOLOGIES LLC, Addison, TX (US)
Filed on Dec. 7, 2021, as Appl. No. 17/543,987.
Application 17/543,987 is a continuation in part of application No. 17/090,420, filed on Nov. 5, 2020, granted, now 11,659,711.
Application 17/090,420 is a continuation in part of application No. 16/849,600, filed on Apr. 15, 2020, granted, now 11,387,244.
Prior Publication US 2022/0093644 A1, Mar. 24, 2022
Int. Cl. H10B 43/27 (2023.01); H10B 41/27 (2023.01); H10D 30/68 (2025.01); H10D 30/69 (2025.01); H10D 64/01 (2025.01)
CPC H10B 43/27 (2023.02) [H10B 41/27 (2023.02); H10D 30/6891 (2025.01); H10D 30/694 (2025.01); H10D 64/035 (2025.01); H10D 64/037 (2025.01)] 1 Claim
OG exemplary drawing
 
1. A memory device, comprising:
an alternating stack of insulating layers and electrically conductive layers;
a memory opening vertically extending through the alternating stack; and
a memory opening fill structure located in the memory opening and comprising a vertical semiconductor channel and a memory film;
wherein:
the memory film comprises a tunneling dielectric layer located in contact with the vertical semiconductor channel, and a vertical stack of charge storage material portions that are vertically spaced apart from each other by lateral protrusion portions of a subset of the insulating layers;
the memory film further comprises a contoured blocking dielectric layer including sac-shaped lateral protrusions that protrude outward from a vertical axis passing through a geometrical center of the memory opening and located at levels of the electrically conductive layers;
the vertical stack of charge storage material portions is located between the contoured blocking dielectric layer and the tunneling dielectric layer within volumes enclosed by the sac-shaped lateral protrusions; and
each of the charge storage material portions comprises:
a toroidal central portion recessed outward from a vertical interface between the insulating layers and the memory opening; and
an annular neck portion adjoined to the toroidal central portion, more proximal to the tunneling dielectric layer than the toroidal portion is to the tunneling dielectric layer, and having a lesser vertical extent than the toroidal portion; and
further comprising a charge storage layer, wherein the charge storage layer comprises:
a vertically-extending cylindrical portion that continuously extends vertically through the electrically conductive layers; and
the vertical stack of charge storage material portions which is adjoined to the vertically-extending cylindrical portion at the neck regions of the charge storage material portions.