South Korean chip heavyweights SK Hynix and Samsung Electronics both surged over 20% in early trading on the Seoul stock exchange Friday. The rally followed strong earnings reports from Amazon and Microsoft, which reignited optimism around artificial intelligence-related spending and triggered a sharp rebound in US tech stocks.

Shares of LG Innotek rose as much as 11.2%, while Seoul Semiconductor gained 7.8%. The broad-based upturn has completely reversed this week's severe sell-off, which had been driven by concerns over stretched valuations in the AI sector. The US iShares Semiconductor ETF (ticker: SOXX) soared over 8% overnight.

Cloud business performance at both US tech giants exceeded expectations, prompting investors to pile back into AI chip-related stocks. Amazon shares climbed more than 9% in after-hours trading, as its second-quarter revenue surpassed market forecasts, fueled by continued strong cloud computing demand. Microsoft jumped over 15% in regular trading Thursday, with its Azure cloud business growing faster than anticipated, further reinforcing confidence that AI infrastructure spending will remain robust.