Technology Development History

Introducing KIOXIA’s achievements in supporting the evolution of electric devices, such as the invention of NAND flash memory in 1987, and advancement of information society on a global scale, seen through the lens of the history of flash memory and SSD development.

*The information on this page is current as of the date of the announcement.

1980s - 1990s

NAND Flash Memory at Dawn

KIOXIA invented the world’s first NAND flash memory in 1987.
NAND flash memory is a storage device that enables large amounts of data to be stored, and it is now an essential part of familiar electronic devices such as smartphones, and data centers.

At the time of commercialization, the mainstream memory capacity was still 4 to 16Mbit (about 1 or 2 songs of music and 1 or 2 photos when converted to the current photo and music data capacity.) From that time, KIOXIA proceeded with development aimed at increasing the capacity with the idea that “flash memory will eventually replace hard disk drives”, and produced breakthrough technology one after another. In 1998, we commercialized 256Mbit NAND flash memory. (256Mbit: about 1 - 2 music CDs / about 16 - 32 photos)

At the time, SSD hadn’t been named “SSD” yet and were called “silicon disk” or “flash drive.”
Advantage of these drives was excellent vibration and shock resistance achieved by not consisting of moving parts such as motors and pickups. For this advantage, they were used in some industrial equipment, but only in a small proportion because drives with NAND flash memory were very expensive compared to HDDs.


  • Invented and announced the world's first* flash memory. Named this non-volatile memory as “Flash” EEPROM (“Flash” Memory) due to its feature of this memory that large amounts of stored data can be erased simultaneously.


  • Invented and announced the world's first* NAND flash memory


  • Commercialized the world's first* 4Mbit NAND flash memory (the world's first* NAND flash memory commercialization)


  • Commercialized the world's first* 16Mbit NAND flash memory. Built-in basic features for NAND flash memory that continues to date.


  • Announced 32Mbit NAND flash memory. Enables 3.3V single power operation instead of previous 5V single power operation.


  • Commercialized 64Mbit NAND flash memory


  • Commercialized the world's first* 256Mbit NAND flash memory. By introducing newly developed self-aligned STI (Shallow Trench Isolation) technology, cell area is significantly reduced.

Column: Changing Lifestyle with Flash Memory

Digital cameras that appeared in the 90s have greatly changed the concept of cameras so far, such as being able to see photos taken on the spot and not having photos not developed. One part of that innovation is memory cards that store data. Following the Smart Media™ that led to the expansion of the NAND flash memory market, various forms of memory cards, including CompactFlash card, Memory Stick, and xD-Picture Cards, were developed by various manufacturers. And SD memory cards, which are still widely used, were commercialized in 2000. The memory card market has expanded along with the increase of performance and capacity of flash memory.
Flash memory came into be used for portable music players which had changed the environment of listening music. With a significantly lighter, smaller, and shock-proof silicon audio player than ever before, people can listen to music anywhere, while playing sports.


Ultra-large-capacity NAND Flash Memory and Market Expansion

As digital products such as mobile phones, smartphones, music players, and digital video cameras prevailed, the need for large capacity and high-performance flash memory had increased. To meet these demands, KIOXIA had developed and manufactured large capacity memory chips by developing technology for miniaturization of memory cells and new circuit and process technology.
In 2007, KIOXIA announced the world’s first 3D flash memory technology, which was subsequently commercialized as “BiCS FLASH™.”
In addition, the development of Solid State Drive (SSD) became full-fledged. After having commercialized SLC NAND-embedded SSDs in 2001, we succeeded in commercialization of client SSDs with flash memory that incorporates multi-level cell technology in the late 2000s. SSDs have come to replace HDDs in notebook PCs, and have greatly contributed to high performance and light-weight notebook PCs.


  • Commercialized 512Gbit SLC (160nm generation) NAND flash memory with simultaneous writing function in 4 pages in a chip


  • Commercialized PATA SSDs (client SSDs) with SLC NAND embedded
  • Commercialized 1Gbit MLC (160nm generation) NAND flash memory which was the first application in the world* of multi-level cell technology to a NAND flash memory product


  • Announced 1Gbit SLC (130nm generation) NAND flash memory which implemented parallel processing technology for data input for writes and data write operations to memory cells


  • Commercialized the world's first* 2Gbit MLC (130nm generation) NAND flash memory


  • Commercialized the world’s first* 4Gbit MLC (90nm generation) NAND flash memory which implemented newly developed self-aligned FG cell technology


  • Commercialized 8Gbit MLC (70nm generation) NAND flash memory which implemented world's first* noise reduction technology between adjacent memory cells


  • Commercialized 16Gbit MLC (56nm generation) NAND flash memory
  • Announced the world's first* 3D flash memory
  • Announced 16Gbit QLC (70nm generation) NAND flash memory which was the first application in the world* of quad-level-cell (QLC) technology to a NAND flash memory product, which implemented new noise reduction technology between adjacent memory cells
  • Announced industry’s largest level* of capacity 128GB SATA SSD (1st generation) embedded with 56nm MLC NAND


  • Commercialized 16Gbit MLC (43nm generation) NAND flash memory with dummy word line technology
  • Announced 16Gbit TLC (56nm generation) NAND flash memory
  • Commercialized industry’s largest level* of capacity 256GB SATA SSD embedded with MLC NAND


  • Announced and commercialized 32Gbit MLC (32nm generation) NAND flash memory with dual patterning process technology
  • Announced 32Gbit TLC (32nm generation) NAND flash memory
  • Announced world’s first* 64Gbit QLC (43nm generation) NAND flash memory
  • Commercialized industry’s largest level* of capacity 512GB SATA SSD (2nd generation) embedded with 43nm MLC NAND
  • Commercialized industry’s first* compact Half Slim SATA/mSATA SSD embedded with 32nm MLC NAND

Column: Smartphones and Flash Memory

The advent of smartphones have changed the world for everyday life and the way we do business, and now is indispensable for our lives. One of the reasons smartphones have become popular is the feature to take photos and videos. Flash memory is also used to record photos and videos.
With improvement of quality of image, storage capacity of smartphones have increased each year, and now some smartphones have 1TB of storage per device. However, even if we need more storage, we cannot size up our smartphone. Thus flash memory is necessary to be placed in a limited space.
Through the development of various technologies, flash memory achieved large capacity and high performance, and supports the large storage of smartphones.


Flash memory from 2D to 3D

After the world’s first announcement of 3D flash memory technology in 2007, mass-produced products were also switched from 2D NAND flash memory to 3D flash memory (BiCS FLASH™) in the mid-2010s. The market for flash memory expanded in achieving more large-capacity memory products.

The market of SSD expanded from mobile PC products to servers and data centers along with the popularization of the Internet and the cloud, which began in the 2000s. Having acquired a lot of storage technologies and product know-hows in the enterprise and data center fields that require high performance and reliability, KIOXIA commercialized enterprise and data center products.


  • Commercialized world’s largest scale of integration* 64Gbit MLC (24nm generation) NAND flash memory with Toggle DDR Interface specification
  • Commercialized stick type SSD (maximum capacity 256GB) that achieves thinner and smaller size compared to mSATA


  • Commercialized enterprise SAS SSDs (100GB, 200GB, 400GB) embedded with 32nm SLC NAND
  • Commercialized world’s smallest* 64Gbit MLC (19nm generation) NAND flash memory


  • Commercialized 128Gbit TLC (19nm generation) NAND Flash memory
  • Announced industry’s largest level* of capacity 1.6TB enterprise SAS SSD. Embedded with 24nm MLC NAND and adopted our proprietary error correction technology “QSBC™”.


  • Commercialized world’s smallest* 64Gbit MLC (19nm 2nd generation) NAND flash memory
  • Commercialized SAS/SATA SSDs embedded with 19nm MLC NAND


  • Commercialized 128Gbit MLC (15nm generation) NAND flash memory with quadruple patterning process technology using the world’s first* 15nm process
  • Commercialized embedded NAND flash memory (64GB) integrated with the industry’s first* UFS I/F


  • Commercialized 48-layer 256Gbit TLC 3D flash memory “BiCS FLASH™”
  • Commercialized world’s smallest* NVMe™ single package SSD
  • Commercialized Serial Interface NAND flash memory


  • Commercialized 64-layer 256Gbit TLC “BiCS FLASH™”
  • Commercialized 2nd generation single package SSDs embedded with “BiCS FLASH™”


  • Commercialized 64-layer 512Gbit TLC “BiCS FLASH™”
  • Announced 64-layer 768Gbit QLC “BiCS FLASH™”
  • Announced 96-layer 512Gbit TLC “BiCS FLASH™”
  • Announced 48-layer TLC “BiCS FLASH™” which implemented the world's first* TSV technology to flash memory
  • Commercialized client and enterprise SSDs embedded with 64-layer “BiCS FLASH™”


  • Announced 96-layer 1.33Tbit QLC “BiCS FLASH™”
  • Commercialized industry's first* SSDs embedded with 96-layer “BiCS FLASH™”
  • Announced NVMe-oF™ software technology (KumoScale™) 
  • Developed Ethernet-connected NVMe-oF™ SSD prototype


  • Announced new storage class memory (SCM) “XL-FLASH™” using 96-layer “BiCS FLASH™” technology
  • Announced removable PCIe®/NVMe™ memory device “XFMEXPRESS™” with new form factor and connector

Column: SSD

SSD stands for Solid State Drive, which uses flash memory as storage medium. SSDs have advantage of high speed, low power consumption and shock resistance compared to Hard Disk Drives (HDDs) which use magnetic disks, but they were initially more expensive than HDDs and that was disadvantageous.
As the cost per bit was lowered by flash memory-intensive technology, we entered a market where we can leverage characteristics of SSDs such as faster PC boot-ups and low power consumption resulting in less heat generation, and users have enjoyed these benefits.

2020 and beyond

Creating a New Market as a Leading Company of Flash Memory and SSDs

Flash memory, which was first developed more than 30 years ago, was then 4Mbit per chip, 10,000 to 100,000 times more expensive than HDDs. After subsequent technology developments and cost reductions, flash memory has been used in products that have changed the society significantly, such as digital cameras, portable music players, smartphones, and SSDs.
KIOXIA’s flash memory and SSDs continue to evolve.


  • Announced 112-layer 512Gbit TLC “BiCS FLASH™”
  • Announced PCIe® 4.0-ready enterprise/data center SSDs
  • Commercialized UFS Ver. 3.1-compliant embedded flash memory
  • Announced Software-Enabled Flash™ (SEF)
  • Announced industry’s first* PCIe® 4.0-ready SSD compliant with Open Compute Project (OCP) “NVMe™ Cloud SSD specification”


  • Announced world’s largest scale of integration* 162-layer 1Tbit TLC “BiCS FLASH™”
  • Commercialized SSDs embedded with our SCM “XL-FLASH™” using “BiCS FLASH™” technology and SLC technology
  • Commercialized SSD products with new form factor “EDSFF E3.S” for PCIe® 5.0 interface


  • Announced world’s largest scale of integration* 162-layer 1Tbit QLC “BiCS FLASH™”
  • Announced 2nd generation 24G SAS SSD product with enhanced performance and security features
  • Announced 2nd generation SSD products for PCIe® 5.0 for next generation data centers

Column: The future of SSDs

As big data and IoT continue to increase, the amount of data handled by both businesses and individuals has increased exponentially. And the capacity and performance of the latest SSDs are exponentially improved, and the capacity of a single computer node being unexpendable. Sharing SSDs across the network is an urgent challenge.
A “software-defined storage solution” has emerged as an approach to solving this challenge. KumoScale™ developed by KIOXIA use a software layer to efficiently manage physical data storage capacity on a server, maximizing the performance of SSDs and thus flash memory.
KIOXIA continues to develop new applications and new markets that are based on flash memory, and that can only be achieved with flash memory.

Explanation of abbreviations

  • SLC: Single Level Cell
  • MLC: Multi Level Cell
  • TLC: Triple Level Cell
  • QLC: Quad Level Cell
  • PATA: Parallel ATA, Parallel Advanced Technology Attachment
  • SATA: Serial ATA, Serial Advanced Technology Attachment
  • mSATA: mini SATA
  • SAS: Serial Attached SCSI (Small Computer System Interface)

KIOXIA has been highly commended for the presentation of its R&D through a variety of channels, including major academic societies and research papers.