Yangtze Memory Technologies Co., Ltd.

Haojie Song

Zhiliang Xia

Kun Zhang

Kun Bao

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, a slit structure, and a staircase local contact. 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 staircase local contact is above and in contact with one of the conductive layers at a staircase structure on an edge of the memory stack. Upper ends of the channel local contact, the slit structure, and the staircase local contact are flush with one another.

Interconnect structures of three-dimensional memory devices

A memory stack including interleaved conductive layers and dielectric layers is formed by replacing, through a slit opening, sacrificial layers with conductive layers. A first source contact portion is formed in the slit opening. Simultaneously, a channel local contact opening is formed through a local dielectric layer to expose a channel structure, and a staircase local contact opening is formed through the local dielectric layer to expose one of the conductive layers at a staircase structure on an edge of the memory stack. Also, simultaneously, a channel local contact, a second source contact portion above a first source contact portion in the slit opening, and a staircase local contact are formed, respectively, in the channel local contact opening, the slit opening, and the staircase local contact opening.

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Wuhan, China

Haojie Song