Patent ID: 11903203
Assignee: MACRONIX INTERNATIONAL CO., LTD.
Field: Computer technology (Electrical engineering)
Classification: CPC H  G | IPC G  H

Claim 12:
13. A fabrication method of a 3D AND flash memory device, comprising:
forming a stack structure on a dielectric substrate, wherein the stack structure comprises a plurality of sacrificial layers and a plurality of insulating layers alternately stacked with each other;
forming an opening in the stack structure;
forming a channel pillar in the opening;
forming a protective cap on the channel pillar;
forming an insulating filling layer on the stack structure and the protective cap, and filling the insulating filling layer in the opening;
patterning the insulating filling layer with the protective cap covering on the channel pillar to form a first hole and a second hole in the channel pillar;
forming a first conductive pillar and a second conductive pillar connected to the channel pillar in the first hole and the second hole, respectively;
performing a replacement process to replace the sacrificial layers with a plurality of gate layers; and
forming a charge storage structure between the gate layers and a sidewall of the channel pillar.