Yangtze Memory Technologies Co., Ltd.

Jianzhong Wu

Jingjing Geng

Zongke Xu

Zhiliang Xia

Wenxi Zhou

Kun Zhang

Zhongwang Sun

Rui Su

Tingting Zhao

A method for forming a three-dimensional (3D) memory device includes forming a dielectric stack including a plurality of first/second dielectric layer pairs over a substrate, forming a plurality of channel structures extending in a lateral direction in a core region of the dielectric stack, forming a staircase structure including a plurality of stairs extending along the lateral direction in a staircase region of the dielectric stack, forming a first drain-select-gate (DSG) cut opening extending in the lateral direction in the core region and a second DSG cut opening in the staircase region, and forming a first DSG cut structure in the first DSG cut opening and a second DSG cut structure in the second DSG cut opening.

Three-dimensional memory devices with drain-select-gate cut structures and methods for forming the same

Embodiments of structures and methods for forming three-dimensional (3D) memory devices are provided. In an example, a 3D memory device includes a core region and a staircase region. The staircase region includes a plurality of stairs each has at least a conductor/dielectric pair extending in a lateral direction. The staircase region includes a drain-select-gate (DSG) cut structure extending along the lateral direction and a vertical direction, and a plurality of support structures extending in the DSG structure along the vertical direction. Of at least one of the support structures, a dimension along the lateral direction is greater than a dimension along a second lateral direction perpendicular to the lateral direction.

A method for forming a 3D memory device is disclosed. A channel structure extending vertically through a dielectric stack including interleaved sacrificial layers and dielectric layers above a substrate is formed. A sacrificial plug above and in contact with the channel structure is formed. A slit opening extending vertically through the dielectric stack is formed. A memory stack including interleaved conductive layers and the dielectric layers is formed by replacing, through the slit opening, the sacrificial layers with the conductive layers. A first contact portion is formed in the slit opening. The sacrificial plug is removed after forming the first contact portion to expose the channel structure. A channel local contact above and in contact with the channel structure, and a second contact portion above the first contact portion in the slit opening are simultaneously formed.

Local contacts of three-dimensional memory devices and methods for forming the same

Three-dimensional (3D) memory devices and methods for forming the 3D memory devices are provided. In one example, a 3D memory device includes a substrate and a memory stack including interleaved conductive layers and dielectric layers on the substrate. The memory stack includes a core structure and a staircase structure. The staircase structure is on one side of the memory stack. The 3D memory device also includes a dummy channel structure extending vertically through the staircase structure. The dummy channel structure includes a plurality of sections along a vertical side of the dummy channel structure. The plurality of sections respectively interface with the interleaved conductive layers in the staircase structure. At least one of the plurality of sections includes a non-flat surface at an interface between the at least one of the plurality of sections and a corresponding conductive layer.

Three-dimensional memory devices having dummy channel structures and methods for forming the same

Embodiments of 3D memory devices and methods for forming the same are disclosed. In an example, a 3D memory device includes a substrate, a memory stack, a channel structure, a channel local contact, and a slit structure. The memory stack includes interleaved conductive layers and dielectric layers above the substrate. The channel structure extends vertically through the memory stack. The channel local contact is above and in contact with the channel structure. The slit structure extends vertically through the memory stack. The slit structure includes a contact including a first contact portion and a second contact portion above the first contact portion and having a different material of the first contact portion. An upper end of the second contact portion of the slit structure is flush with an upper end of the channel local contact.

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Wuhan, China

Jianzhong Wu