Sandisk Technologies Inc.

Yoshinobu Tanaka

Koichi Ito

Yoshitaka Otsu

Akihiro Tobioka

Sung Tae Lee

Naoto Hojo

Kei Nozawa

Yashushi Doda

Hideaki Hasegawa

Naoki Takeguchi

Kensuke Yamaguchi

Genta Mizuno

Yusuke Mukae

Hirofumi Tokita

Yusuke Ikawa

Yujin Terasawa

Takeshi Kawamura

Ryoichi Ehara

Shiori Kataoka

Ryosuke Itou

Zhiwei Chen

An alternating stack of insulating layers and sacrificial material layers is formed over a substrate. Memory openings and support openings are formed through the alternating stack, and memory opening fill structures and support pillar structures are formed in the memory openings and in the support openings, respectively. Via cavities extending to each of the sacrificial material layers are formed through the alternating stack without forming any stepped surfaces in the alternating stack. The via cavities may be formed in areas that do not overlap with the support pillar structures, or in areas that include at least one support pillar structure. Sacrificial via fill structures are formed in the via cavies, and the sacrificial material layers are replaced with electrically conductive layers. The sacrificial via fill structures are removed, and a combination of a tubular dielectric spacer and a contact via structure can be formed in the via cavities.

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

A method of forming a three-dimensional memory device includes forming a vertically alternating sequence of insulating layers and spacer material layers over a substrate, such that the spacer material layers are formed as, or are subsequently replaced with, electrically conductive layers, iteratively performing a first set of non-offset layer patterning processing steps at least twice to form a first part of a terrace region including a set of stepped surfaces which extend in a first horizontal direction, and performing a second set of offset layer patterning processing steps to form a second part of the terrace region and to form a stepped vertical cross-sectional profile for patterned surfaces of the vertically alternating sequence along a second horizontal direction which is perpendicular to the first horizontal direction.

Three-dimensional memory device containing horizontal and vertical word line interconnections and methods of forming the same

A multi-tier three-dimensional memory array includes multiple alternating stacks of insulating layers and electrically conductive layers that are vertically stacked. Memory stack structures including memory films and semiconductor channels extend through the alternating stacks. The alternating stacks are formed as alternating stacks of insulating layers and sacrificial material layers, and are subsequently modified by replacing the sacrificial material layers with electrically conductive layers. Structural support during replacement of the sacrificial material layers with the electrically conductive layers is provided by the memory stack structures and dielectric support pillar structures. The dielectric support pillar structures may be formed only for a first-tier structure including a first-tier alternating stack of first insulating layers and first spacer material layers, or may vertically extend over multiple tiers. The dielectric support pillar structures may be formed before or after formation of stepped surfaces in the alternating stack.

Multi-tier three-dimensional memory device with dielectric support pillars and methods for making the same

An alternating stack of insulating layers and sacrificial material layers is formed with stepped surfaces. Sacrificial metal plates are formed on the top surfaces of the sacrificial material layers, and a retro-stepped dielectric material portion is formed over the sacrificial metal plates. Contact via cavities are formed through the retro-stepped dielectric material portion employing the sacrificial metal plates as etch stop structures. The sacrificial metal plates are replaced with portions of insulating spacer layers. Sacrificial via fill structures within remaining volumes of the contact via cavities. The sacrificial material layers are replaced with electrically conductive layers. The sacrificial via fill structures are replaced with portions of staircase-region contact via structures that contact the electrically conductive layers.

Three-dimensional memory device containing replacement contact via structures and method of making the same

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Yokkaichi, Japan

Yoshinobu Tanaka