Toshiba and SanDisk have jointly developed a flash memory chip capable of storing twice as much data as their current largest-capacity flash memory, they announced.

The new chip can store 4Gbits (512KBytes) of data and the companies said they are also working on a second new chip that contains two of the 4Gb chips inside a single case for what is effectively an 8Gb (1GB) flash memory chip.

For users of digital still cameras, MP3 players and memory sticks, this means that devices can either be made smaller while carrying the same amount of memory or kept the same size with the internal memory capacity increasing.

Such advances are typical in memory technology and employ more advanced production methods to achieve chips with a higher memory density. The companies are planning to begin mass production of 300,000 chips per month of both the 4Gb and 8Gb chips from the third quarter of this year. Production will be handled by Flash Vision Japan, a joint-venture between Toshiba and Sandisk, using a 90-nanometer production process, they said.

Samples of the 4Gb chip will be available from this month for ¥12,000 (around £65)) and of the 8Gb chip from May at ¥24,000 (£130), said Toshiba. Estimate prices for the chips at the time of mass production were not announced.

A third new chip, containing a stack of four of the new chips to produce an effective 16Gb (or 2GB) flash memory chip, is also expected to be available in sample quantities from the third quarter, said Toshiba.