Flash memory is a type of non-volatile memory storage, which can be electrically erased and programmed. What was the event that precipitated the introduction of this new storage medium?
Well, it started in the mid-1980s, when Toshiba was working on a project to create a replacement for the EEPROM, a low-cost type of non-volatile memory, which could be erased and reprogrammed. The problem with the EEPROM was its cumbersome erasure process; it needed to be exposed to an ultraviolet light source to perform a complete erasure. To overcome this challenge, the E2PROM was created. The E2PROM type of memory cell was block erasable, but it was eight times the cost of the EEPROM. The high cost of the E2PROM led to rejection from consumers who wanted the low cost of EEPROM coupled with the block erasable qualities of the E2PROM.
This market desire led to the creation of what became known as the NOR architecture at Toshiba. While Toshiba was the first to create a NOR-based flash memory cell, the first commercially successfully design did not arrive until the late 1980s and was known as the ETOX Cell. The ETOX
cell was slow to write and slow to erase, but was quick to read. This low-capacity NOR architecture became the industry standard replacement for read-only memory. From there came new advances in storage technology, which has had a radical impact on the storage market as well as on data center economics. This paper discusses both the technical aspects of flash storage as well as the economic impact it has had.