But major Japanese suppliers have said factories producing these chips were largely unaffected by the temblor, nor are they in areas where blackouts will force production to stop. While it appears by their statements that the memory markets are overreacting to the earthquake, analysts say that the price increases may highlight a graver issue for the global chip industry: damage to Japanese component and material suppliers vital to chip production.
The price of NAND flash memory, which has grown in importance as the main data storage in iPads, iPhones and other mobile devices, has increased by as much as 20 percent since the earthquake struck as companies try to figure out if chip factories in the area were damaged.
Although prices rose, not many people were selling, according to DRAMeXchange, which runs an online clearinghouse for NAND, DRAM and other chips. Most companies seemed more interested in keeping their supplies of the chips instead of taking a quick profit.
The NAND market has reacted so strongly because Japan supplies as much as 40 percent of the world's NAND flash chips, according to Jim Handy , at Objective Analysis.
Toshiba, one of the biggest NAND suppliers in the world, said none of its NAND flash memory factories were hurt by the earthquake or tsunami.
The company's only chip factory in the area of the earthquake is in Kitakami City, Iwate prefecture, and produces logic chips, not memory chips. Production at the factory stopped as soon as the earthquake hit and it remains out of operation, Toshiba said.
The chip factories where Toshiba makes NAND flash memory are in Yokkaichi City, Japan, around 500 miles away from the earthquake's epicenter and the area hit by the tsunami.
"Two (factories) temporarily stopped operations on March 11, Japan time, but afterward resumed operation and are now operating normally," Toshiba said. "We are still carefully examining any possible impact on the production equipment caused by the earthquake but the effect so far is minimal."
Prices of DRAM, the most widely made memory chips used in PCs, laptops and servers, surged 7 percent after the earthquake was reported, according to market researcher iSuppli, and then settled down.
Elpida Memory, Japan's only major DRAM maker, has said its DRAM factories weren't affected by the earthquake. The company's main chip factory is in Hiroshima, in the southwest of Japan, well over 500 miles away from the earthquake.
While Japanese factories producing NAND and DRAM appear to have made it through the earthquake relatively unscathed, some of the world's largest suppliers of key materials used in chip production, such as the silicon wafers that chips are etched onto, have had to halt production.
Sumco Corporation and Shin-Etsu Chemical, which supply most of the world's silicon wafers, both ceased production at factories near where tsunamis swept entire towns into the sea and damaged the cooling systems of one of Japan's nuclear power plants.
Sumco said its factory in Yonezawa was shut after the earthquake. No employees were hurt, and after it does a safety check it hopes to get the factory running again.
Shin-Etsu said three of its factories, one each in Annaka, Kamisu, and Nishigo Village, all stopped after the earthquake.
Production equipment at two of the factories, in Kamisu and Nishigo Village, was damaged, but "at present it is still unclear how long it will take to restore such damaged equipment and facilities at both plants," the company said in a statement Tuesday.
Sumco holds a 35 percent share of the 300-millimeter (12-inch) silicon wafer market, while Shin-Etsu holds 30 percent, according to Credit Suisse. Japanese companies supply 72 percent of the world's silicon wafers overall, the investment bank added.
The companies also expect power outages in the area to hurt production.
Aside from the nuclear plants, thermal and hydro power plants were also shut down after the earthquake, according to Tokyo Electric Power Co., and it is working to restore power. Nearly a third of its capacity was knocked offline by the earthquake.
The power company started rolling blackouts on Monday, affecting people and companies in northeastern Japan.
Global chip giants including Taiwan Semiconductor (TSMC) and South Korea's Samsung Electronics have said they don't expect any near-term impact from the silicon wafer problem. Chip makers always hold some inventory of wafers and can rely on distributors as well.
But should the current situation continue over the longer term there could be problems.
"Our checks indicate foundries, raw wafer suppliers and distributors have inventory of 1-2 months, so would be impacted if the delay extends out," Credit Suisse said.
