Sandisk Technologies Inc.

Yoshitaka Otsu

Naoto Hojo

Takaaki Iwai

Junpei Kanazawa

Kei Nozawa

Hisakazu Otoi

Hirofumi Tokita

Koichi Ito

Masanori Terahara

Yoshinobu Tanaka

Koichiro Nagata

Yashushi Doda

Takahiro Tabira

Fumiaki Toyama

Satoshi Shimizu

Yuki Mizutani

Mitsuteru Mushiga

Kota Funayama

Eiji Hayashi

Yusuke Ikawa

Shuji Minagawa

Takeshi Kawamura

Ryoichi Ehara

Takuya Sakurai

Kazuto Ohsawa

Muneyuki Imai

Makoto Koto

Yasushi Doda

Hisaya Sakai

Zhiwei Chen

Yoshiyuki Kuroko

A three-dimensional memory device includes an alternating stack of insulating layers and electrically conductive layers, memory stack structures vertically extending through the alternating stack, a perforated dielectric moat structure including a dielectric fill material and vertically extending through the alternating stack. The perforated dielectric moat structure includes, at each level of the insulating layers, two rows of lengthwise dielectric pillar portions laterally extending along a first horizontal direction and two columns of widthwise dielectric pillar portions extending along a second horizontal directions that is perpendicular to the first horizontal direction. Each row of lengthwise dielectric pillar portions has a first center-to-center pitch. Each column of widthwise dielectric pillar portions has a second center-to-center pitch. A ratio of the second center-to-center pitch to the first center-to-center pitch is in a range from 1.50 to 2.0.

Three-dimensional memory device with dielectric isolated via structures and methods of making the same

A semiconductor structure includes semiconductor devices located on a top surface of a substrate semiconductor layer, lower-level metal interconnect structures embedded in lower-level dielectric material layers, source-level material layers, an alternating stack of insulating layers and electrically conductive layers overlying the source-level material layer, memory stack structures, a vertically alternating sequence of insulating plates and dielectric material plates laterally surrounded by the alternating stack, an isolation trench fill structure interposed between the alternating stack and the vertically alternating sequence and including a trench fill material portion and a capping dielectric structure overlying the trench fill material portion, and a first through-memory-level interconnection via structure vertically extending through each plate within the vertically alternating sequence and contacting a top surface of one of the lower-level metal interconnect structures.

Three-dimensional memory device containing a capped isolation trench fill structure and methods of making the same

A three-dimensional memory device includes an alternating stack of insulating layers and electrically conductive layers located over a substrate, memory stack structures vertically extending through the alternating stack, a finned dielectric moat structure including a dielectric core portion vertically extending through each layer within the alternating stack and a vertical stack of dielectric fin portions laterally extending outward from the dielectric core portion, a vertical stack of insulating plates and dielectric material plates laterally surrounded by the finned dielectric moat structure, and an interconnection via structure vertically extending through the vertical stack and contacting a top surface of an underlying metal interconnect structure.

Three-dimensional memory device with via structures surrounded by perforated dielectric moat structure and methods of making the same

A semiconductor device includes an alternating stack of insulating layers and electrically conductive layers located over a substrate including a semiconductor material layer, a memory opening and a support opening extending through the alternating stack, a memory opening fill structure located in the memory opening and including a memory film and a semiconductor material portion in contact with the semiconductor material layer, and a support pillar structure located in the support opening. The support pillar structure lacks a semiconductor material portion which is in contact with the semiconductor material layer.

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

A method of forming a three-dimensional memory device includes forming a first-tier alternating stack of first insulating layers and first sacrificial material layers, forming first-tier memory openings, first-tier support openings, and first-tier moat trenches through the first alternating stack using a same etching step, forming a first dielectric moat structure in the first moat tier-trenches and first support pillar structures in the first-tier support openings during a same deposition step, forming memory stack structures in the first-tier memory openings, forming backside trenches through the first-tier alternating stack after forming the first dielectric moat structure, replacing portions of the first sacrificial material layers with first electrically conductive layers through the backside trenches, and forming at least one through-memory-level interconnection via structure through the first vertically alternating sequence of first insulating plates and first dielectric material plates surrounded by the first dielectric moat structure.

Three-dimensional memory device including multi-tier moat isolation structures and methods of making the same

A three-dimensional memory device can include at least one alternating stack of insulating layers and electrically conductive layers located over a semiconductor material layer, memory stack structures vertically extending through the at least one alternating stack, and a vertical stack of dielectric plates interlaced with laterally extending portions of the insulating layers of the at least one alternating stack. A conductive via structure can vertically extend through each dielectric plate and the insulating layers, and can contact an underlying metal interconnect structure. Additionally or alternatively, support pillar structures can vertically extend through the vertical stack of dielectric plates and into an opening through the semiconductor material layer, and can contact lower-level dielectric material layers embedding the underlying metal interconnect structure to enhance structural support to the three-dimensional memory device during manufacture.

Three-dimensional memory device including through-memory-level via structures and methods of making the same

Fabricating a three-dimensional memory device may include forming an alternating stack of insulating layers and sacrificial material layers over a substrate. Stepped surfaces are formed by patterning the alternating stack. Sacrificial pads are formed on physically exposed horizontal surfaces of the sacrificial material layers. A retro-stepped dielectric material portion is formed over the sacrificial pads. After memory stack structures extending through the alternating stack are formed, the sacrificial material layers and the sacrificial pads can be replaced with replacement material portions that include electrically conductive layers. The electrically conductive layers can be formed with thicker end portions. Contact via structures can be formed on the thicker end portions.

Three-dimensional memory device including locally thickened electrically conductive layers and methods of manufacturing the same

A three-dimensional memory device includes an alternating stack of insulating layers and electrically conductive layers located over a substrate, memory stack structures vertically extending through the alternating stack, a perforated dielectric moat structure vertically extending through the alternating stack, and an interconnection via structure laterally surrounded by the perforated dielectric moat structure and vertically extending through each insulating layer within the alternating stack. Each of the memory stack structures includes a vertical semiconductor channel and a vertical stack of memory elements located at levels of the electrically conductive layers. The perforated dielectric moat structure includes a plurality of lateral openings at each level of the insulating layers, and does not include any opening at levels of the electrically conductive layers. An interconnection via structure can be laterally surrounded by the perforated dielectric moat structure, and can vertically extend through each insulating layer within the alternating stack.

A three-dimensional memory device includes alternating stacks of insulating layers and electrically conductive layers located over a substrate, a first memory array region and a second memory array region that are laterally spaced apart along the first horizontal direction by an inter-array region therebetween, and memory stack structures extending through the alternating stacks in the first or second memory array region. Each of the alternating stacks includes a respective terrace region in which layers of a respective alternating stack have variable lateral extents within an area of the inter-array region, and a respective array interconnection region laterally offset from the respective terrace region and which continuously extends from the first memory array region to the second memory array region. Each of the alternating stacks has a width modulation along a second horizontal direction that is perpendicular to the first horizontal direction within the area of the inter-array region.

Three-dimensional memory device containing width-modulated connection strips and methods of forming the same

A three-dimensional memory device includes alternating stacks of insulating layers and electrically conductive layers located over a semiconductor material layer, and memory stack structures extending through one of the alternating stacks. Laterally-undulating backside trenches are present between alternating stacks, and include a laterally alternating sequence of straight trench segments and bulging trench segments. Cavity-containing dielectric fill structures and contact via structures are present in the laterally-undulating backside trenches. The contact via structures are located within the bulging trench segments. The contact via structures are self-aligned to sidewalls of the alternating stacks. Additional contact via structures may vertically extend through a dielectric alternating stack of a subset of the insulating layers and dielectric spacer layers laterally adjoining one of the alternating stacks.

Three-dimensional memory device containing eye-shaped contact via structures located in laterally-undulating trenches and method of making 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.

A vertically alternating sequence of continuous insulating layers and continuous sacrificial material layers is formed over a substrate, and is patterned to form stepped surfaces. Memory stack structures are formed in a memory array region of the alternating stack. Support pillar structures are formed through the vertically alternating sequence within a staircase region. The support pillar structures are formed at lattice sites of a hexagonal lattice structure that includes unoccupied lattice sites. Portions of the continuous sacrificial material layers are replaced with electrically conductive layers. Contact via structures are formed on a respective one of the electrically conductive layers at the unoccupied lattice sites. Geometrical centers of the support pillar structures are arranged at vertices of a polygon having more than four vertices having a respective contact via structure located at a geometric center of the polygon in a plan view.

Three-dimensional memory device containing a polygonal lattice of support pillar structures and contact via structures and methods of manufacturing the same

A source-level sacrificial layer and an alternating stack of insulating layers and sacrificial material layers are formed over a substrate. Memory openings are formed through the alternating stack, and a source cavity is formed by removing the source-level sacrificial layer. A memory film is formally formed by a conformal deposition process, and a source contact layer is formed in the source cavity. Vertical semiconductor channels and drain regions are formed in remaining volumes of the memory openings on sidewalls of the source contact layer. A backside contact via structure is formed through the alternating stack and directly on a sidewall of the source contact layer.

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Yokkaichi, Japan

Yoshitaka Otsu