ben850, yes, micrometer is 0.000001 meter. The wafers start at around 775um, so they are backgrinding way down to get to 30um.
I'm thinking there's something missing here with regards to future device capacity. Toshiba was a primary supplier for the 32GB Iphone with 8 32Gb chips per package on their 43nm technology. However, since a 43nm 32Gb flash is too big to fit into a standard TSOP package, Apple had to modify their board to allow Toshiba's single package to occupy the space of the traditional two TSOPs they've had in iphones.
My point is that at 32 nm , 32 Gb fits in a TSOP, so that change alone doubles the amount of memory an iphone can carry. Throw in 16 chips per package instead of 8, and it doubles again. Could be looking at 128GB iphones in that scenario. And with 64Gb chips coming out in 2010 or early 2011, could see 256GB iphones with two 16 chip TSOP packages.