The site says that the main silicon wafer plant operated by Shin-Etsu Handotai , in Skirikawa, has shut down due to a lack of electricity.

FORBES: Memory Chip Prices Spike After Quake On Tighter Supplies

The reduction reflects the suspension of operations at two plants: Shin-Etsu Chemnical has stopped manufacturing operations at its facility in Shirakawa, while MEMC Electronic Materials (WFR) has shut its Utsunomiya facility.

FORBES: Japan Quake Knocked Out 25% Of Global Silicon Wafer Production