How it began
Fujio Masuoka invented flash memory while working at Toshiba. Wikipedia, citing Toshiba, dates the invention to 1980, while the Computer History Museum states that he developed the flash memory cell in 1984. Masuoka and colleagues presented NOR flash at the 1984 International Electron Devices Meeting in San Francisco and NAND flash at the same meeting in 1987. According to Toshiba, the name was suggested by Masuoka's colleague Shoji Ariizumi, because the erasure process reminded him of the flash of a camera.
Before it existed
Flash is based on earlier EEPROM technology. EPROM chips had to be erased completely before they could be rewritten. Early floating-gate memory required engineers to build a memory cell for each bit of data, which proved cumbersome, slow and expensive. In the 1970s this restricted floating-gate memory to niche uses such as military equipment and the earliest experimental mobile phones.
How it spread
Toshiba commercially launched NAND flash memory in 1987, and Intel introduced the first commercial NOR-type flash chip in 1988. The Computer History Museum notes that the industry's first commercially successful flash products emerged after Masuoka's work at Toshiba. Later chips rose from 4 megabits to gigabits, and in 2007 Toshiba introduced packages built from stacked NAND chips.
Who pushed back
The Computer History Museum summarizes the episode under the heading "Inventing Memory, but Feeling Forgotten": Masuoka's idea won praise, but Masuoka did not, and he was unhappy with how Toshiba treated him. IEEE Spectrum, in its Chip Hall of Fame, describes him as a Toshiba factory manager who decided to reinvent semiconductor memory.
