Yangtze River storage and Micron chip war upgrade. Changjiang, a 3D NAND flash memory manufacturer, has filed a lawsuit in the US District Court for the Northern District of California against Micron Technology, the US memory chip leader, accusing Micron of infringing on eight US patents related to 3D NAND.

According to reports, the US patents stored by Yangtze River in this case, It includes US10,950,623 (3D NAND memory device and its formation method), US11,501,822 (non-volatile storage device and control method), US10,658,378 (TAC for 3D memory device), and US10,937,806 (TAC for 3D memory device) (TAC)), US10,861,872 (3D memory element and its forming method), US11,468,957 (architecture and method of NAND memory operation), US11,600,342 (reading method of 3D flash memory), US10,868,031 (multi-layer stacked 3D memory element and its manufacturing method).

Yangtze River Storage said in the complaint that Micron's 128 layer, 176 layer and many other series of 3D NAND infringed Yangtze River Storage's eight patents. Micron's unauthorized use of Changjiang Storage's patented technology to compete with Changjiang Storage to protect market share infringed upon Changjiang Storage's interests and curdled the impetus for innovation.

In recent years, with 3D NAND technology stacked to 128 layers or even higher, the peripheral CMOS circuit will occupy more than 50% of the chip area. In order to solve this problem, Changjiang Storage launched its own innovative Xtacking technology in 2018.

Founded in July 2016 and headquartered in Wuhan, Hubei Province, Changjiang Memory is an IDM integrated circuit enterprise focusing on 3D NAND flash memory design and manufacturing integration, as well as providing complete memory solutions.

The CAC announced on May 21 this year that Micron's products sold in the mainland had serious network security problems and had not passed the review, so mainland operators should stop purchasing Micron's products, representing that Micron's products would face a ban crisis in the mainland.

According to the Financial Times, the United States imposed export restrictions on advanced chip production equipment in October 2022, and listed 36 Chinese companies such as Yangtze River Storage on a trade blacklist.

The investigation found that Micron has been playing a "commercial rake" role for many years, in the early years of US-Japan semiconductor competition, Micron has controlled the dumping of DRAM products by many Japanese companies, plus more than 170 lobbying content submitted by Micron in the past four years are related to the mainland, based on the above two reasons, reasonable doubt that Micron this time around the land memory chip industry, Micron may be behind the driving force.