EP3850660

• Yangtze Memory Technologies Co., Ltd.seit 18. Juni 2021; EPA-Eintragungen enden 15. Aug. 2025

Embodiments of three-dimensional (3D) memory devices having through stair contacts (TSCs) and methods for forming the same are disclosed. In an example, a method for forming a 3D memory device (100) is disclosed. A dielectric stack (104) including a plurality of interleaved dielectric layers (112) and sacrificial layers (110) is formed on a substrate (102). A staircase structure (142) is formed on one side of the dielectric stack (104). A dummy hole extending vertically through the staircase structure (142) and reaching the substrate (102) is formed. A spacer (138) having a hollow core is formed in the dummy hole. A TSC (136) in contact with the substrate (102) is formed by depositing a conductor layer (140) in the hollow core of the spacer (138). The TSC (136) extends vertically through the staircase structure (142).

Aus der internationalen Anmeldung WO2020140190