Rapid Development of 3D NAND Flash Memory: Market Share, Layer Stacking, and Patent Trends (2010‑2019)

The article begins by examining NAND flash market share from 2010 to 2018, highlighting Samsung’s consistent leadership despite fluctuations, and noting Western Digital’s rise after acquiring SanDisk and other flash companies.

It then details the swift advancement of 3D NAND technology, describing how Samsung introduced 32‑layer V‑NAND in 2015, followed by SK Hynix, Micron/Intel, and Toshiba/WD launching 36‑, 48‑, and 64‑layer products, and mentions China’s Yangtze Memory Technologies (YMTC) achieving 3D NAND development.

By 2018, 64‑layer products from the three major camps and SK Hynix’s 72‑layer V4 were in mass production, while YMTC announced its Xtacking™ 3D NAND technology, aiming for 32‑layer volume production in 2019.

The piece discusses the projected continuation of layer growth, with 96‑layer samples already demonstrated in 2018 and expectations of 128‑layer products emerging later in 2019.

Beyond layer count, the article highlights innovative stacking techniques such as Intel/Micron’s Multi‑stack 3D NAND, SK Hynix’s 4D NAND, and YMTC’s Xtacking™, which enables separate processing of I/O and memory cell circuits on a single wafer, improving speed and functionality.

Patent trends are analyzed using LexInnova data: early patent activity began in 1995, with a notable surge in 2006 after SanDisk’s increased filings, a dip during the 2008‑2010 financial crisis, and a rapid rise from 2011‑2013. Subsequent fluctuations are explained by reporting lags.

Figures illustrate patent rankings, showing SanDisk (later part of Western Digital) and Taiwan’s Macronix as leading patent holders, and note a 2018 ITC ruling where Toshiba was ordered to pay $40 million to Macronix for patent infringement.

The article concludes that while the United States, Japan, and South Korea dominate patent counts, Chinese firms are increasingly active in 3D NAND patent filings, indicating a growing global competition in stacked memory technology.