US AI Semiconductor Equipment Parts Stocks Surge by 900 Billion Won in a Day

Ultra Clean Holdings, Inc. (NASDAQ: UCTT) saw its share price surge 10.12% on the Nasdaq, closing at $130.84. Trading volume reached about 1.07 million shares, and the company’s market capitalization rose to roughly $5.865 billion—equivalent to about ₩8.2 trillion—gaining approximately $660 million (₩920 billion) in a single day.

After reporting first-quarter revenue and earnings that beat market expectations at the end of April and announcing its CFO’s retirement, Ultra Clean has attracted strong institutional and retail buying in June. This momentum follows an AI-driven earnings surprise, the unveiling of a $4 billion revenue target for 2030, and a series of record-high stock prices. Investor confidence has also been bolstered by the recent issuance of $600 million in zero-percent convertible senior notes and anticipation ahead of the company’s second-quarter earnings release scheduled for July 27.

Headquartered in Hayward, California, Ultra Clean supplies ultra-high-purity gas and fluid delivery modules and components, as well as cleaning and contamination-analysis services, to semiconductor equipment manufacturers such as Applied Materials and Lam Research. The company is viewed as a classic semiconductor equipment supply-chain play, offering significant leverage—and corresponding volatility—to wafer fab equipment investment trends, particularly as spending on AI and high-bandwidth memory accelerates.