US 2022/0189872 A1 · THREE-DIMENSIONAL MEMORY DEVICE INCLUDING STAIRLESS WORD LINE CONTACT STRUCTURES FOR AND METHOD OF MAKING THE SAME

Abstract

A three-dimensional memory device includes an alternating stack of insulating layers and electrically conductive layers located over a substrate, memory openings located in a memory array region and vertically extending through the alternating stack, memory opening fill structures located in the memory openings, and laterally-isolated contact via assemblies located in a contact region. Each of the laterally-isolated contact via assemblies includes a contact via structure contacting a top surface of a respective one of the electrically conductive layers and an insulating spacer laterally surrounding the contact via structure and having an outer surface having a corrugated vertical cross-sectional profile in which first portions of the insulating spacer located at levels of the electrically conductive layers laterally protrude outward relative to second portions of the insulating spacer located at levels of the insulating layers.

Claims20

Dependent claims

A three-dimensional memory device comprising:

an alternating stack of insulating layers and electrically conductive layers located over a substrate;
memory openings located in a memory array region and vertically extending through the alternating stack;
memory opening fill structures located in the memory openings;
and
laterally-isolated contact via assemblies located in a contact region, wherein each of the laterally-isolated contact via assemblies comprises a contact via structure contacting a top surface of a respective one of the electrically conductive layers and an insulating spacer laterally surrounding the contact via structure and having an outer surface having a corrugated vertical cross-sectional profile in which first portions of the insulating spacer located at levels of the electrically conductive layers laterally protrude outward relative to second portions of the insulating spacer located at levels of the insulating layers.

2 more elements

A method of forming a three-dimensional memory device, comprising:

forming an alternating stack of insulating layers and sacrificial material layers over a substrate;
forming memory openings through the alternating stack in a memory array region;
forming memory opening fill structures comprising a memory film and a vertical semiconductor channel in the memory openings;
forming via cavities in a contact region through a respective subset of layers within the alternating stack by performing anisotropic etch processes;
forming via cavity fill structures in the via cavities, wherein each of the via cavity fill structures comprises an insulating spacer and a sacrificial via fill material portion embedded within the insulating spacer which completely fill the via cavities;
replacing the sacrificial material layers with electrically conductive layers while the via cavities are completely filled with the via cavity fill structures;
removing the sacrificial via fill material portions selective to the insulating spacers;
and
forming contact via structures vertically extending through a bottom portion of a respective one of the insulating spacers to a top surface of a respective underlying one of the electrically conductive layers.

6 more elements

Dependencies are inferred from the claim text.

Three-dimensional memory device including stairless word line contact structures for and method of making the same

Life of this patent

Three-dimensional memory device including stairless word line contact structures for and method of making the same

Life of this patent

Abstract

Claims20