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Chip Hall of Fame: Toshiba NAND Flash Memory

Once, all bulk data storage was magnetic. Then along came flash

2 min read
Toshiba NAND Flash Memory chip
Photo: Fujio Masuoka

Toshiba NAND Flash Memory chipImage: Fujio Masuoka

NAND Flash Memory

Manufacturer: Toshiba

Category: Memory and Storage

Year: 1989

The saga that is the invention of flash memory began when a Toshiba factory manager named Fujio Masuoka decided he’d reinvent semiconductor memory. We’ll get to that in a minute. First, a bit of history is in order.

Before flash memory came along, the only way to store what passed for large amounts of data at the time was to use magnetic tapes, floppy disks, or hard disks. Many companies were trying to create solid-state alternatives, but the choices, such as EPROM (or erasable programmable read-only memory, which required ultraviolet light to erase the data) and EEPROM (the extra E stands for “electrically,” doing away with the UV) couldn’t store much data economically.

Enter Masuoka at Toshiba. In 1980, he recruited four engineers to a semisecret project aimed at designing a memory chip that could store lots of data and would be affordable. Their strategy was simple. “We knew the cost of the chip would keep going down as long as transistors shrank in size,” says Masuoka, now CTO of Unisantis Electronics, in Tokyo.

Masuoka’s team came up with a variation of EEPROM that featured a memory cell consisting of a single transistor. At the time, conventional EEPROM needed two transistors per cell. It was a seemingly small difference that had a huge impact on cost.

In search of a catchy name, they settled on “flash” because of the chip’s ultrafast erasing capability. Now, if you’re thinking Toshiba rushed the invention into production and watched as the money poured in, you don’t know much about how huge corporations typically exploit internal innovations. As it turned out, Masuoka’s bosses at Toshiba told him to, well, erase the idea.

He didn’t, of course. In 1984 he presented a paper on his memory design at the IEEE International Electron Devices Meeting, in San Francisco. That prompted Intel to begin development of a type of flash memory based on NOR logic gates. In 1988, the company introduced a 256-kilobit chip that found use in vehicles, computers, and other mass-market items, creating a nice new business for Intel.

That finally pushed Toshiba to greenlight Masuoka’s invention. His flash chip was based on NAND technology, which offered greater storage densities but proved trickier to manufacture. Success came in 1989, when Toshiba’s first NAND flash hit the market. And just as Masuoka had predicted, prices kept falling.

Digital photography gave flash a big boost in the late 1990s, and Toshiba became one of the biggest players in a multibillion-dollar market. At the same time, though, Masuoka’s relationship with other executives soured, and he quit Toshiba. (He later sued for a share of the vast profits and won a cash payment.)

Today, NAND flash is a key piece of gadgets and space probes alike—and is beginning to replace even hard disks as the storage medium of choice in laptop and desktop computers.

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The Godfather of South Korea’s Chip Industry

How Kim Choong-Ki helped the nation become a semiconductor superpower

15 min read
A man in a dark suit, bald with some grey hair, leans against a shiny blue wall, in which he is reflected.

Kim Choong-Ki, now an emeritus professor at Korea Advanced Institute of Science and Technology, was the first professor in South Korea to systematically teach semiconductor engineering.

Korea Academy of Science and Technology

They were called “Kim’s Mafia.” Kim Choong-Ki himself wouldn’t have put it that way. But it was true what semiconductor engineers in South Korea whispered about his former students: They were everywhere.

Starting in the mid-1980s, as chip manufacturing in the country accelerated, engineers who had studied under Kim at Korea Advanced Institute of Science and Technology (KAIST) assumed top posts in the industry as well as coveted positions teaching or researching semiconductors at universities and government institutes. By the beginning of the 21st century, South Korea had become a dominant power in the global semiconductor market, meeting more than 60 percent of international demand for memory chips alone. Around the world, many of Kim’s protégés were lauded for their brilliant success in transforming the economy of a nation that had just started assembling radio sets in 1959 and was fabricating outdated memory chips in the early ’80s.

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