On April 21, 2026, Kioxia Corporation announced the immediate suspension of production at its advanced NAND flash memory manufacturing site in Kitakami, Iwate Prefecture. The decision followed a magnitude 7.7 earthquake that occurred at approximately 2:15 PM local time, with its epicenter located off the coast of Miyagi Prefecture. The seismic event triggered automatic safety protocols across the facility, leading to an orderly shutdown of the K1 fabrication plant to protect both personnel and sensitive manufacturing equipment.
The Iwate facility is one of Kioxia’s most critical production hubs, specializing in high-density 3D NAND flash memory, including the latest BiCS FLASH generations. According to an official statement from Kioxia, the earthquake reached a seismic intensity of 6 Upper on the Japanese scale in parts of Iwate. While no immediate structural failures were reported at the K1 plant, the company confirmed that sensitive semiconductor manufacturing equipment, including extreme ultraviolet lithography and deep ultraviolet lithography systems, underwent automatic emergency stops. These systems require precise nanometer-level calibration, and even minor tremors can lead to wafer misalignment or mechanical damage to the internal components.
Kioxia is currently evaluating the status of wafers that were mid-process at the time of the shutdown. Semiconductor fabrication involves hundreds of sequential steps over several months; a sudden loss of power or mechanical vibration can result in the loss of entire batches of silicon. The company has not yet provided a specific timeline for the resumption of operations, stating that thorough inspections of the cleanroom environment and utility systems—including ultra-pure water and chemical delivery lines—are mandatory before restarting the lines. The K2 facility, which is currently under expansion and partial operation, is also being inspected for structural integrity and equipment displacement.
The suspension comes at a time when the Kitakami site accounts for a significant portion of Kioxia’s total NAND output. Western Digital, Kioxia’s joint venture partner, issued a brief acknowledgment of the situation, noting that it is working closely with Kioxia to determine the impact on their shared production capacity. Initial reports from the region indicate widespread power outages and transportation disruptions, though Kioxia’s facility is equipped with uninterruptible power supply systems designed to prevent catastrophic equipment damage during the initial seconds of a grid failure.
As of 8:00 PM local time on April 21, Kioxia reported that all employees at the Iwate site had been accounted for and no injuries were sustained on-site. The company has established an emergency task force to coordinate with local utility providers and logistics partners. Further updates regarding the duration of the downtime and the extent of the impact on production yields are expected following the completion of technical assessments over the next several days.