3D NAND flash memory device and manufacturing method thereof

• Main Authors: MOON JAE HWAN, GAO WEI, KIM HAN-SOO, SHEN NYU
• Format: Patent
• Language: Chinese; English
• Published: 01.08.2023
• Subjects: ELECTRICITY

The invention relates to the technical field of semiconductor memory devices, in particular to a 3D NAND flash memory device and a manufacturing method thereof. The manufacturing method comprises the steps that a semiconductor substrate layer is provided firstly, a unit isolation structure, a channel structure and a source electrode leading-out space are formed on the semiconductor substrate layer, and the unit isolation structure is of a stacked structure and comprises a unit isolation layer and a storage unit occupied space. And sequentially depositing a first dielectric layer and a second dielectric layer, wherein the first dielectric layer at least covers the exposed surface of the unit isolation structure. Etching the second dielectric layer, removing all the second dielectric layer on the side surface, removing at least part of the second dielectric layer on the second surface, reserving all the second dielectric layer on the first surface, and forming an electron capture layer of the storage unit struc