7 facts filed under 3D structure and process: 2 read in the original source and 5 reported by a second source. Each was checked against the source’s own words, so its figures appear there, and each names where it comes from. The idea is taught in Part 4, 3D NAND Stacking.
Primary sources
Micron pairs charge trap with a replacement-gate architecture that uses highly conductive metal wordlines instead of a silicon layer; the release does not name the metal.
Micron’s 176-layer NAND is its fifth generation of 3D NAND and second-generation replacement-gate architecture.
Secondary sources
TCAT introduced gate replacement with tungsten fill, and Samsung used a tungsten replacement gate from its first V-NAND generation in 2013.
Samsung’s first V-NAND (2013) used the tungsten replacement gate of TCAT, which lowered wordline resistance against the original BiCS polysilicon plates.
TCAT’s gate replacement deposits the metal gates by filling the space between the wordlines with tungsten.
TCAT was the foundation of V-NAND, the first 3D NAND architecture in volume production, launched at Flash Memory Summit 2013.
The metal gate of TCAT, the basis of V-NAND, reduces the parasitic resistance of the wordline, which translates into faster operations.
Sources
Primary is the original paper, standard or datasheet. Secondary is a review, a vendor summary or a news report. Measured is my own test data.
Show all 4 sources, 2 primary
- PrimaryMicron Technology, Inc. - Micron Ships World’s First 176-Layer NAND, Delivering A Breakthrough in Flash Memory Performance and Density
- SecondaryArchitectural and Integration Options for 3D NAND Flash MemoriesComputers, 2017
- Secondary3D Flash MemoriesSpringer, 2016
- PrimaryMicron Ships World’s First 176-Layer NAND, Delivering A Breakthrough in Flash Memory Performance and Densityinvestors.micron.com