The NAND-type flash memory is designed to have faster rewrite characteristics and higher storage volume than NOR type memory, and is used in memory card formats such as Smart Media, Compact Flash and SD (secure digital) cards for mobile devices.
The companies released their first 1Gbit flash memory last November using stacked 512Mbit chips and multilevel cell technology to store several bits of information per cell.
However, the multilevel technology slowed the memory's data reading speed, according to Kenichi Sugiyama, a Toshiba spokesman. Toshiba has been in partnership with SanDisk on the development of NAND-type flash memory since 1999.
By February Toshiba and SanDisk were able to develop a flash memory chip that could hold up to 1Gbit. The latest product uses this chip and the single-level cell technology, still has a fast reading speed, Sugiyama said.
By adopting the advanced 0.13-micron technology for the 1Gbit chip, the companies were also able to reduce the chip size.
Samples of the chip in TSOP (thin small outline package) packaging were shipped yesterday at ¥8,000 (£43) and samples in an LGA (land grid array) package will be available next month, also at ¥8,000. Mass production of the both products is expected to start at the end of this year, at the rate of 300,000 units a month.
Toshiba also planned to commercialise a 2Gbit flash memory by combining two 1Gbit chips. Samples are expected to be available in October at ¥17,000 (£92), and mass production to begin at the end of this year.