On August 2, domestic flash memory manufacturer Cheung Kong Memory announced at the Flash Memory Summit 2022 (FMS) that it officially launched the crystal stack based? 3.0 (Xtacking? 3.0) technology of the fourth generation TLC 3D flash X3-9070.

According to the information, the 3D NAND flash stack may have reached the industry-leading 232 layers.

Changjiang Storage 4th generation TLC 3D flash memory X3-9070

According to reports, X3-9070 compared with the previous generation of products, has higher storage density, faster I/O speed, and the use of 6-plane design, performance improvement and lower power consumption, further release the potential of system-level products.

Specifically, the X3-9070 has the following technical features:

Performance:

Implements the X3-9070Up to 2400MT/s I/O transmission rate, in line with ONFI 5.0 specification; Compared to Changjiang storage last generation productsAchieved 50% performance improvement;

Density:

Thanks to the architecture innovation of crystal stack 3.0, X3-9070 has become the highest density flash memory particle product in Changjiang Memory history.Capable of achieving 1Tb of storage capacity in a smaller single chip;

Improve system-level product experience:

Thanks to theInnovative 6-Plane design(This means that DIE can be allowed to do more parallel processing, which can lead to better random read throughput), X3-9070 compared to traditional 4-plane,Performance is improved by more than 50%, while power consumption is reduced by 25%, the energy efficiency ratio is significantly improved, which can bring more attractive total cost of ownership (TCO) to end users.

According to CJC, the X3-9070 has passed a number of test standards defined by the Joint Electronic Device Engineering Commission (JEDEC) with outstanding performance, improved durability and high quality reliability.

Although CJC has not disclosed the specific number of stacked layers for the X3-9070, according to supply chain sources, it has reached an industry-leading 232 layers.

It's worth noting that at the end of July this year, Micron just officially announced the industry's first 232-layer stacked 3D NAND chip, which was the world's first mass-produced 3D NAND flash chip with more than 200 layers at that time, and the world's first 6-plane designed 3D NAND flash chip.

After only a few days, Changjiang Storage also successfully launched the 232-layer stacked X3-9070, successfully catch up with the industry's top level, it is really very powerful.

So why has Yangtze Storage, founded in 2016, taken just six years to catch up with the world's leading technology? Yangtze River storage original Xtacking technology is indispensable!

According to the data, Cheung Kong Memory's Xtacking technology processes the peripheral circuits responsible for data I/O and memory unit operations independently on one wafer, while the memory unit is processed independently on another wafer.

When both wafers are completed, Xtacking technology only needs one processing step to connect them through millions of metal VIA(Vertical Interconnect channels), and thus only receives a limited increase in cost.

According to data previously released by Changjiang Storage, in traditional 3D NAND architecture, peripheral circuits account for about 20~30% of the chip area, which also reduces the memory density of the chip significantly.

As 3D NAND technology stacks up to 128 layers and higher, peripheral circuits can take up more than 50% of the chip area. Xtacking puts peripheral circuits on top of memory cells, achieving higher storage density than traditional 3D NAND.

In addition, in terms of I/O speed, the current NAND flash memory is mainly Intel/ SONY /SK Hynix/Collective/Western Digital/Micron's main push ONFi. The latest ONFI 5.0 standard, released in 2021, has a maximum I/O interface speed of 2.4Gbps.

Cheung Kong's Xtacking 1.0 technology, which went into mass production in 2019, has dramatically increased the I/O interface speed to 3Gbps, matching the I/O speed of DRAM DDR4.

Cheung Kong Storage said the Xtacking technology not only improves I/O interface speeds, but also ensures higher capacity for 3D NAND multilayer stacking. It also reduces product development time by three months and production cycle time by 20 percent, significantly shortening the development to market time for 3D NAND products.

According to an analysis report by Tech Insights that dismantled and tested Yangtze Storage's 512Gb 128-layer Xtacking 2.0 TLC chip in October last year,The DIE size of the chip is 60.42mm², the unit density increased to 8.48 Gb/mm², a 92% improvement over the previous generation's 256Gb 64-layer Xtacking 1.0 Die. The read speed is up to 7500 MB/s and the write speed is up to 5500 MB/s.

△ DIE plan of CMOS peripheral circuit for Cheung Kong storage 512Gb 128-layer Xtacking 2.0 TLC NAND chip

△ Comparison of three generations of Changjiang Storage 3D NAND: Gen1 (32L), Gen2 (64L, Xtacking 1.0) and Gen3 (128L, Xtacking 2.0).

Today, the Xtacking technology for Yangtze Storage has been further evolved into Xtacking 3.0, which is a big improvement over Xtacking 2.0.