학술논문

Highly Manufacturable 7th Generation 3D NAND Flash Memory with COP structure and Double Stack Process
Document Type
Conference
Source
2021 Symposium on VLSI Technology VLSI Technology, 2021 Symposium on. :1-2 Jun, 2021
Subject
Bioengineering
Computing and Processing
Photonics and Electrooptics
Power, Energy and Industry Applications
Couplings
Three-dimensional displays
Process control
Very large scale integration
Market research
Flash memories
Stress
flash memory
3D NAND
double Stack
COP
Language
ISSN
2158-9682
Abstract
A novel 3D NAND Flash memory device with 17X WL (Word line) layers has been successfully developed. COP(Cell Over Peripheral) Structure has been applied, improving tR and tPROG by 11% and 20%, respectively. Compared with our previous product(6 th generation), the bit density is increased by 70% through cell volume scaling and COP structure. Several breakthrough processes have been successfully combined to achieve this new structure. Double stack process, low stress W(tungsten), MSE(Multi Step Etch), and channel hole side-wall butting etc. In addition, the double stack process was applied to significantly improve the channel hole profile. As a result, better cell operation characteristics were achieved.