[DigitalToday intern reporter Seung-a Yoo] Semiconductor stocks rebounded sharply on July 30. Strong results and demand outlook from Microsoft and Lam Research revived investor sentiment, spreading buying across chip names that had fallen recently.

CNBC reported that the standout was Lam Research. The stock rose 20 percent, its biggest one-day gain since 1999. The company posted solid results and guidance backed by demand for artificial intelligence. Microsoft shares also climbed 15 percent after it signalled strong growth in its Azure business and said it would increase capital spending to reflect solid demand.

The rebound was seen as partly reversing recent market concerns about a potential slowdown in AI infrastructure investment. Semiconductor stocks have been in focus as AI beneficiaries as companies increased investment in memory and central processing units. Over the past few sessions, selling continued as concerns grew that the spending expansion was nearing a peak, and more than $1 trillion in market capitalisation was wiped out early this week.

Memory-related stocks also rose sharply. After Samsung Electronics warned that a memory supply shortage could last until 2028, Micron rose 13 percent and SanDisk gained 21 percent. The stocks had been weak in recent sessions following SK Hynix results that fell short of expectations.

Semiconductor exchange-traded funds also climbed. The iShares Semiconductor ETF rose 8 percent. Applied Materials and AMD each rose about 13 percent, Intel gained 12 percent and Marvell Technology rose 10 percent. Nvidia also rose 2 percent.

Arm Holdings also rose 6 percent. The company said demand was strong for its first in-house chip, a CPU for artificial general intelligence. Chief Executive Rene Haas (르네 하스) said demand for the product exceeded $2 billion across fiscal 2027 and fiscal 2028. In an interview with CNBC on July 30, he said, "Demand for the product is large. More importantly, it shows that the CPU market around agentic workloads and inference is key. We are seeing that market continue to grow."

The rebound showed that earnings and demand outlook still drive the direction of semiconductor share prices. Signals of increased capital spending from Microsoft, Lam Research guidance based on AI demand, and Samsung Electronics' warning of a prolonged memory bottleneck came at the same time, helping revive chip investment sentiment after a recent sharp correction.