A new NAND flash memory fabrication facility, producing 300mm wafers, has been commissioned by Toshiba and SanDisk in Japan. 

Toshiba started building Fab 4 in August 2006, in response to continuous rising demand for NAND flash memory used in a wide range of digital applications, including digital media players, mobile phones, PCs and memory cards.Fab 4 is expected to start mass production in December 2007 and reach a
production capacity of 80 000 wafers a month in the second half of 2008.
The fab still has space to expand capacity, and further investment could take output to 210 000 wafers per month, in response to the projected increase in future market demand.
Fab 4 will employ 56-nanometer (nm) process technology at start-up, and plans call for a gradual transition to 43nm technology, starting from March 2008.
Fab 4 is designed to minimise any impact on operations from natural disasters. The building was constructed using the latest earthquake-absorbing structure, which is designed to dampen temblor force by up to two-thirds, and deploys multiple power compensation (MPC) that is triggered instantaneously by any sudden, momentary loss of power supply – from a lightning strike, for example.
Toshiba funded construction of the Fab 4 building, and Flash Alliance, a Toshiba-SanDisk venture established in July 2006, is funding the advanced manufacturing equipment now being   installed in the fab.