The 3D NAND flash memory market shared by the giants has a place for domestic manufacturers

The day before yesterday, TrendForce Jibang Consulting released the NAND Flash market report for the third quarter of 2021. In the third quarter, thanks to the strong demand for smart phone and server applications, NAND flash chip shipments increased by nearly 11%, the average sales unit price increased by nearly 4%, and the industry’s total revenue reached 18.88 billion US dollars, up 15% month-on-month.
The 3D NAND flash memory market divided up by giants has a place for domestic manufacturers
Revenue ranking of global NAND Flash brand manufacturers in the third quarter of 2021 (unit: USD million), source: TREND FORCE
In terms of revenue, most manufacturers’ revenue increased compared with the previous quarter. From the perspective of market share, the top three giants Samsung, Armor and SK Hynix have split up about 67% of the market share, and their market share has increased compared with Q2. The head manufacturers have begun to erode the market share of the rear manufacturers.
NAND flash memory is the second largest segment of the memory market, accounting for 42% of the size of the memory market. In 2020, the global semiconductor market size is $440.2 billion, the memory market size is $117.2 billion, and the NAND flash memory market size is $49.4 billion.
The 3D NAND flash memory market divided up by giants has a place for domestic manufacturers
Source: IC Insights
The market scale and market position of NAND flash memory determine its “extraordinary”. Technology iteration and product update have attracted much attention.
General trend: from 2D to 3D
Since the introduction of NAND flash memory in the 1980s, the NAND flash memory technology has undergone earth-shaking changes.
Previously, NAND flash memory has always been based on 2D plane NAND technology, which is what we call 2D NAND flash memory. 2D miniaturizes the transistor size on the plane to obtain higher storage density, but the transistor size miniaturization meets the physical limit, and now faces the bottleneck, reaching the development limit. In order to achieve capacity improvement while maintaining performance, 3D NAND has become the mainstream of development. 3D NAND has changed the solution idea from simply improving the manufacturing process to stacking multiple layers, successfully solving the problem of reducing the performance of planar NAND while increasing the capacity, and achieving all-round improvement in capacity, speed, energy efficiency and reliability. In 2019, the penetration rate of 3D NAND was 72.6%, which has far exceeded that of 2D NAND, and will continue to increase in the future. It is estimated that 3D NAND will account for 97.5% of the total flash memory market in 2025.
The 3D NAND flash memory market divided up by giants has a place for domestic manufacturers
Source: International business strategies
Since NAND flash memory entered the 3D era, the number of stack layers has become higher and higher like skyscrapers, from the original 24/32 layers to the current 128 or even 176 layers. The higher the number of layers, the greater the capacity NAND flash memory can have. Increasing the number of layers and increasing the output are also the criteria to measure the technical strength.
The 3D NAND flash memory market divided up by giants has a place for domestic manufacturers
Source: Yole
In 2019, 64/72 layers of 3D NAND output accounted for 64.9%, which was the main part of global output, and 92 layers of 3D NAND output accounted for 21.3% of the total. According to DRAMeXchange, with the introduction of 110+layer flash memory chips, 92/96 layers will be replaced rapidly, and the output share will gradually decline after a slight increase in 2020. It is estimated that 72.5% of the total market output will be occupied by 110+layer 3D NAND flash memory in 2023. According to people familiar with the matter, next year, mobile phones and consumer solid-state drives will increasingly use 176-layer 3D NAND flash memory.
Major manufacturers have taken measures to expand production in order to occupy the market as much as possible, and are also moving towards more layers of technology.
Samsung: Innovate the “V NAND” architecture and seize the first opportunity of 200+layers
As the leading enterprise of NAND flash memory, Samsung has been associated with 3D NAND flash memory for a long time. The wind of 3D NAND flash memory has been blowing to the world from Samsung in 2013. In 2013, Samsung designed a method of vertically stacking units, which concentrated the units on a single floor (similar to high-rise apartments), which is also the world’s first 3D unit structure “V-NAND”. The V-NAND launched by Samsung that year can realize up to 24 layers of die stacking through 3D stacking technology. In addition, Samsung also announced that the write speed and reliability of V-NAND flash memory have been improved more than twice.
The 3D NAND flash memory market divided up by giants has a place for domestic manufacturers
Source: Samsung
The technological progress of Samsung’s V-NAND flash memory is to abandon the traditional floating gate MOSFET and use its own charge capture flash (CTF) design. Because of the insulation of the traditional floating grid, adjacent cells are easy to interfere with each other. Samsung uses the insulated silicon nitride film as the isolation layer of the electrons to “shut down” the electrons to prevent mutual interference, and then “unlock” them when they need to be read. The greatest advantage of this isolation method is that it can reduce the charge interference between storage cells to a greater extent, thus greatly improving the write speed of the chip and increasing the P/E erase times of the chip. V-NAND flash memory with CTF structure is considered as a non-planar design, with the insulator surrounding the channel and the control gate surrounding the insulator layer. This 3D structure design improves the physical area where the charge is stored, and improves the performance and reliability.
The 3D V-NAND architecture continues to mature in the verification of NAND flash memory history. Samsung has also maintained its dominant position in the NAND flash memory market through technology change and expansion of production lines.
Samsung’s technology research and development has never been slow. Last year, Samsung launched the leading 176-story seventh generation “V-NAND”. Samsung official said that compared with the sixth generation of 100-layer V-NAND, the volume of the seventh generation of V-NAND unit is reduced by 35%, 176 layers can be placed without increasing the module height, and at the same time, the power consumption can be reduced and the efficiency can be improved by 16%. The 176-layer NAND flash memory has been mass produced; The day before yesterday, at the Samsung Technology Forum, Samsung took the lead in announcing the details of the eighth generation V-NAND in the industry. The stack has more than 200 layers, and the capacity can reach 1Tbit. The thickness of 512GB capacity is only 0.8mm, which can be used for mobile phones. It is expected to be mass produced in the second half of next year.
In addition to technology, Samsung’s capacity expansion has also kept pace. The day before yesterday, according to a source quoted by the Electronic Times, Samsung Electronics will also install a new 3D NAND chip production line in the third factory of Hirazawa (P3) to increase the output of 176-layer 3D NAND chips. At that time, it will have a monthly capacity of 40000 to 50000 pieces.
Meguiar: the first mass production of 176-layer 3D NAND flash memory, winning at the starting line
Last October, Meguiar announced that it had mass-produced the world’s first 176-layer 3D NAND flash memory. Meguiar’s 176-layer 3D NAND flash memory is the fifth generation of Meguiar’s 3D NAND product. Through the application of the proprietary CuA (CMOS under-array, CMOS array) architecture, combined with the new array structure using the replacement grid technology and new cell structure, the breakthrough 176-layer NAND innovation has been achieved. All of these combined to create a 176-layer NAND with efficient CuA 3D architecture. CuA technology builds a multi-layer stack on the logic device of the chip, integrates more memory into a more compact space, greatly reduces the size of 176 layers of NAND bare chip, and improves the storage capacity of a single wafer.
Compared with the previous generation of high-capacity 3D NAND, Meguiar’s 176-layer 3D NAND flash memory has improved read latency and write latency by more than 35%, which can significantly improve application performance.
The 3D NAND flash memory market divided up by giants has a place for domestic manufacturers
Source: Meguiar
Meguiar launched the world’s first 176-layer 3D NAND in the first place, making the technical competition between manufacturers more intense.
Armor: NAND technology and NIL technology work together
Similar to Samsung, the relationship between Armor and NAND flash memory can be traced back to the 1980s, when the predecessor of Armor, Toshiba Storage, developed NAND flash memory. Over the past few decades, Armor still stands on the top of NAND flash memory.
At the end of January last year, Japanese flash chip company Kioxia and Western Digital jointly announced that they had developed the sixth-generation 162-layer 3D flash memory technology, which increased the density by 10% compared with the previous generation’s 162-layer flash memory.
In addition to constantly updating NAND flash memory technology, Armor also started with lithography technology and cooperated with Canon and DNP to develop nano-imprint lithography (NIL) process technology. Compared with the currently commercialized EUV lithography technology, Armour Xia said that NIL technology can significantly reduce energy consumption and reduce equipment costs. The reason is that the NIL technology has a relatively simple micro-imaging process, and the power consumption can be reduced to 10% of the EUV technology, and the equipment investment can be reduced to only 40% of the EUV equipment. For Armor, NAND flash memory is easier to adapt to the NIL technology process because of its 3D stacking structure. Armor Xia also said that the basic technical problems of NIL have been solved and the promotion of mass production technology is under way. He hopes to be the first to be introduced into NAND production compared with other competitors.
In addition to focusing on improving technology, Armor also increased production capacity by building new factories.
In May of this year, Armour is estimated to invest up to about 2 trillion yen (about 18.37 billion US dollars), and the increased investment will help improve 3D NAND production. Armour plans to list a new K2 factory in northern Iwate, Japan, and plans to start operation in 2023. At present, Armour Xia has carried out land engineering on about 150000 square meters of land adjacent to the east and north sides of K1. In addition to investing in K2 plants and facilities, it also includes the cost of supplementing the equipment in the factory of Sunichi. In addition, Armour is also building a Fab7 factory in Sikyi, Japan. The construction of the factory is divided into two stages. The first stage is planned to be completed in the spring of 2022.
Changjiang Storage: strength and courage coexist
According to the statistics of Minsheng Securities in July 2021, China is the second largest NAND market in the world, accounting for about 31%, but the local supply market accounts for less than 1%.
The 3D NAND flash memory market divided up by giants has a place for domestic manufacturers
Source: Minsheng Securities Research Institute
However, as a leading storage manufacturer in China, Changjiang Storage is expected to lead the rise of the domestic NAND industry by continuously shortening the distance from the world’s leading level.
In October 2017, Changjiang Storage successfully designed and manufactured China’s first 3D NAND flash memory.
In September 2019, the company used Xtacking? 1.0 Architecture flash technology, successful mass production of 64-layer TLC 3D NAND flash memory. Unlike the traditional 3D NAND architecture, Xtacking? Technology belongs to independent innovation. In the traditional NAND architecture, the peripheral circuits and memory cells operated by I/O and memory cells are manufactured on the same wafer. Store Xtacking in Yangtze River? In the architecture, the peripheral circuits operated by I/O and memory cells are produced on one wafer, while the memory cells are independently processed on the other wafer. When the two wafers are processed separately, Xtacking? The technology only needs one processing step to bond the two through billions of metal vertical interconnection channels (VIA, Vertical Interconnect Access) to connect the circuit and package them into the same chip.
Later, given that the world’s leading manufacturers have more than 100 layers of technology, Changjiang Storage decided to skip the 96-layer common in the industry and directly develop 128-layer 3D NAND. In April 2020, Changjiang Storage announced the successful development of 128-layer 3D NAND, which has been mass produced this year.
epilogue
The localization rate of 1% represents not the lack of domestic NAND flash memory, but the technological path that many domestic manufacturers are trying to catch up with. This road can be slow, and slow can be studied with ingenuity; But we must also strive to go fast, so that we can catch up with the rapidly changing technological iteration.