Most of Taiwan's wafer fabs lost electrical power around 1:47 a.m. when the quake struck, causing silicon foundries to shut down normal operations and switch on emergency power generators (see Sept. 20 story). With the back-up power on, managers at Taiwan Semiconductor Manufacturing Co. and other wafer foundries here are still attempting to determine if production lines and tools need repairs or servicing before they are started again.

Some companies indicated that employees have not yet entered into some cleanrooms for fear of gas leaks. Normal electrical power is not expected to be restored for days, according to several companies interviewed today.

Back-up generators at some fabs are providing enough power to protect wafer-processing tools and to help managers assess the potential damage. TSMC officials indicated that the company's use of standard mechanical interface (SMIF) minienvironments in fabs may have helped to protect wafers that were in the midst of being processed when the quake struck.

According to analysts tracking the impact of the quake, Taiwan foundry operations are not likely to resume until later this week, if power is restored in the next couple of days.

A Hong Kong-based analyst with Goldman, Sachs & Co. said he did not believe the quake and disruption in fab operations would be catastrophic financially to Taiwan's growing foundry industry. Assuming a three-day shutdown at TSMC, the analyst said the world's largest silicon foundry could end up losing about NT$630 million ($19.8 million), or about 3% of its expected third-quarter revenues.

TSMC, United Microelectronics Corp., and other Taiwan chip makers today released initial assessments of the conditions in their facilities, which appeared to escape major structural damage. No deaths were reported at semiconductor operations. More than 1,000 people died in Taiwan, and buildings in Taipei did sustain major damage from the strongest earthquake to hit the country in nearly a century.

"First of all, we are thankful to report that there were no injuries to UMC Group employees," said Jim Ballingall, vice president of worldwide marketing for UMC, based in Sunnyvale, Calif. "Also, there is no apparent damage to the fab buildings or machinery, except for some glass breakage. While back-up power has been on since the disruption in the main power in the early morning in Taiwan, most fab equipment can not be fully tested for functionality until the main power is restored."

Immediately after the quake, semiconductor managers worldwide attempted to find out if Taiwan's growing silicon foundry industry had suffered any major damage. About two-thirds of the world's third-party foundry capacity is located in Taiwan, said the U.S.-based Fabless Semiconductor Association, citing data presented at last week's Semicon Taiwan conference.

"The good news seems to be that there is no structural damage being reported by the foundries--in particular TSMC, but the bad news is the power outages," said Jodi Shelton, executive director of the Fabless Semiconductor Association, who is based in Dallas.

Additional reporting by J. Robert Lineback from the U.S.