Why are NAND Flash Fabs so Huge?

NAND Economies of ScaleMany readers have probably wondered why NAND flash fabs are so enormous.  Although DRAM fabs used to be the largest, running around 60,000 wafers per month, NAND flash fabs now put that number to shame, running anywhere from 100,000-300,000 wafers per month.  Why are they so huge?

The reason is that you need to run that many wafers to reach the optimum equipment balance.  The equipment must be balanced or some of it will be sitting idle, and with some tools costing $50 million (immersion scanners) you want to minimize their idle time to the smallest possible number.  I am sure that this is a tough problem, although I have never had to solve it myself.

The most important reason that so much attention is focused on this is that the cost of the wafer depends on the efficiency of the fab.  If you built a $13 billion NAND flash fab that produced 90,000 wafers per month instead of 100,000 wafers per month, then the amount of investment per wafer would be 10% higher.  That can make a significant difference to Continue reading

Hynix Squeaks Out Another Update

Hynix Wuxi FireIn its own uniquely minimalistic style, Hynix has updated the status of the second line of its Wuxi fab, the one that was hit by a fire on September 4:

We would like to provide the following update on the recovery status of  SK Hynix Wuxi fab that was affected by the fire on Wednesday September 4, 2013. The air ventilation system and cleanroom in the line that was affected by the fire have now been substantially restored, and we have resumed partial utilization in this line from Thursday October 10, 2013. We will gradually raise utilization and make every effort to recover normalized level of pre-fire utilization in November as planned.

This statement should put to rest Continue reading