Semiconductor stocks shot up dramatically on Wednesday evening, with the sector gaining more than $400 billion in market value after upbeat financial forecasts from Micron Technology and Qualcomm gave new momentum to Wall Street’s artificial intelligence stock rally, which had been losing steam in recent days.
Micron Technology led the charge, surging 12% in after-hours trading. The company projected quarterly earnings that topped what analysts had anticipated, a signal that the enormous amounts of money being poured into AI infrastructure will fuel robust demand for its memory chips.
Qualcomm also made headlines after the closing bell, announcing it expects its data center business to generate $15 billion in sales by 2029. The chipmaker is working to expand beyond its traditional smartphone chip business and redirect its focus toward artificial intelligence.
Other companies in the storage and memory space also saw big gains. Western Digital, Sandisk, and Seagate Technology — all competitors of Micron — each climbed more than 8%.
Elsewhere in the chip sector, Arm Holdings rose roughly 6%, Marvell gained nearly 4%, and Broadcom added 2%. Equipment suppliers Applied Materials and ASML, which provide specialized manufacturing tools to semiconductor companies, both gained more than 4%.
The strong outlooks from Micron and Qualcomm come after a rough stretch on Wall Street, where investors had grown increasingly nervous that AI-related stock prices had climbed too high after years of gains. The PHLX chip index dropped 8% on Tuesday alone, as concerns mounted that the massive spending required to build out AI data centers might take too long to translate into meaningful revenue and profits.
Despite this week’s turbulence, the PHLX chip index is still up 90% for the year so far in 2026. And even before Wednesday’s late-session rally, Micron had already gained more than 260% year to date.
