Patent ID: 11968834
Assignee: SANDISK TECHNOLOGIES, INC.
Field: Semiconductors (Electrical engineering)
Classification: CPC H | IPC H

Claim 3:
4. A three-dimensional memory device comprising:
an alternating stack of insulating layers and electrically conductive layers located over a substrate;
memory openings vertically extending through the alternating stack and having lateral protrusions at levels of the electrically conductive layers; and
memory opening fill structures located in the memory openings,
wherein each of the memory opening fill structures comprises a vertical semiconductor channel, a dielectric material liner laterally surrounding the vertical semiconductor channel, and a vertical stack of discrete memory elements laterally surrounding the dielectric material liner and located within volumes of the lateral protrusions,
wherein each discrete memory element within the vertical stack of discrete memory elements comprises a vertical inner sidewall and a convex outer sidewall that is laterally offset outward from the vertical inner sidewall by a greater lateral offset distance at a central segment thereof than at a top segment thereof and than at a bottom segment thereof,
wherein the convex outer sidewall of each discrete memory element is adjoined to the vertical inner sidewall of a respective discrete memory element,
wherein an entirety of the convex outer sidewall of each discrete memory element is convex; and
wherein:
the plurality of vertical outer sidewall segments of each stepped outer sidewall comprise at least five vertical outer sidewall segments that are laterally offset from the vertical semiconductor channel by at least three different lateral offset distances; and
the plurality of horizontal outer sidewall segments of each stepped outer sidewall comprise at least six horizontal outer sidewall segments that are vertically spaced from the substrate by different vertical distances.