公开(公告)号：US10957706B2

公开(公告)日：2021-03-23

申请号：US16276952

申请日：2019-02-15

Applicant: SANDISK TECHNOLOGIES LLC

Inventor： Yoshitaka Otsu ,  Kei Nozawa ,  Yashushi Doda ,  Naoto Hojo ,  Yoshinobu Tanaka ,  Koichi Ito

IPC: H01L27/11582 ,  H01L27/11565 ,  H01L27/1157 ,  H01L27/11573 ,  H01L23/522 ,  H01L21/311 ,  H01L21/28 ,  H01L21/768 ,  H01L27/11556 ,  H01L27/11519 ,  H01L27/11524 ,  H01L27/11526

Abstract: 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.

公开(公告)号：US20200286916A1

公开(公告)日：2020-09-10

申请号：US16880365

申请日：2020-05-21

Applicant: SANDISK TECHNOLOGIES LLC

Inventor： Naoto Hojo ,  Takahiro Tabira ,  Yoshitaka Otsu

IPC: H01L27/11582 ,  H01L27/11573 ,  H01L21/768 ,  H01L27/11565 ,  H01L21/311 ,  H01L21/28 ,  H01L27/1157

Abstract: 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.

公开(公告)号：US10700089B1

公开(公告)日：2020-06-30

申请号：US16273523

申请日：2019-02-12

Applicant: SANDISK TECHNOLOGIES LLC

Inventor： Naoto Hojo ,  Takahiro Tabira ,  Yoshitaka Otsu

IPC: H01L27/11582 ,  H01L27/11565 ,  H01L27/1157 ,  H01L27/11573 ,  H01L21/311 ,  H01L21/768 ,  H01L21/28 ,  H01L27/11556 ,  H01L27/11519 ,  H01L27/11524 ,  H01L27/11526

Abstract: 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.

公开(公告)号：US11355515B2

公开(公告)日：2022-06-07

申请号：US16880365

申请日：2020-05-21

Applicant: SANDISK TECHNOLOGIES LLC

Inventor： Naoto Hojo ,  Takahiro Tabira ,  Yoshitaka Otsu

IPC: H01L27/11582 ,  H01L27/11565 ,  H01L27/1157 ,  H01L27/11573 ,  H01L21/311 ,  H01L21/768 ,  H01L21/28 ,  H01L27/11556 ,  H01L27/11519 ,  H01L27/11524 ,  H01L27/11526

Abstract: 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.

公开(公告)号：US10971514B2

公开(公告)日：2021-04-06

申请号：US16276996

申请日：2019-02-15

Applicant: SANDISK TECHNOLOGIES LLC

Inventor： Yoshitaka Otsu ,  Kei Nozawa ,  Yashushi Doda ,  Naoto Hojo ,  Yoshinobu Tanaka ,  Koichi Ito ,  Zhiwei Chen ,  Yusuke Ikawa ,  Takeshi Kawamura ,  Ryoichi Ehara

IPC: H01L27/11582 ,  H01L27/11565 ,  H01L27/1157 ,  H01L27/11573 ,  H01L23/522 ,  H01L21/311 ,  H01L21/28 ,  H01L21/768 ,  H01L27/11556 ,  H01L27/11519 ,  H01L27/11524 ,  H01L27/11526

Abstract: 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.