Surging demand for memory chips and related equipment amid the AI boom has boosted shares of EO Technics in South Korea by over 40% so far this year. The stock rise has made the company’s founder and CEO, Sung Kyu-dong, a billionaire.

With a 28% stake, Sung, 68, is the largest shareholder of EO Technics, which is listed on South Korea’s technology-rich Kosdaq stock exchange. His wife, Chung Yoon-hye, and two sons combined hold an additional holding of close to 2%. Forbes estimates Sung and his family’s net worth at $1 billion as of Friday’s stock market close.

Based in Anyang, south of Seoul, EO Technics makes laser-based equipment used in the production of memory chips. Its flagship product is the CSM (Chip Scale Marker), equipment that etches identification codes onto chips to provide traceability, allowing manufacturers to quickly isolate the source of any defects. The company’s revenue rose 19% from a year ago to 381 billion won ($253 million) in 2025, while net income increased 35% to 58 billion won over the same period.

“In the existing flagship Marker equipment division, sales are expected to continue growing steadily in calendar 2026, driven by the effects of new line investments, such as Samsung’s Taylor line in Texas, and the recovery of the NAND market,” IM Securities analyst Song Myung-sub said in a research note last week. “The increasing demand for laser marking on EMI [electromagnetic interference] shields and heat sinks due to the chiplet conversion of AI semiconductors is also a positive factor for the division's performance.”

The company’s other major product is LA (Laser Annealing), which uses a laser to finish the electrical pathways inside the chip (a process called dopant activation), providing the targeted heat needed to make them functional without damaging the rest of the memory stack. “With the increase in NAND stacking, the benefits for the company's laser annealing equipment are expected to become more pronounced starting from next year,” Song said in the report. “As higher stacking layers generate more heat, it is judged that the annealing method in NAND is highly likely to shift from a total heat treatment method to a localized laser processing method.”

Sung founded EO Technics in 1989 and listed it on the South Korea stock exchange in 2000. Before starting EO Technics, Sung worked at Goldstar Central Research Center (the predecessor to LG Electronics Research Institute), Daewoo Heavy Industries (the flagship subsidiary of Daewoo Group before the conglomerate went bankrupt in 1999) and Korea Laser, which pioneered industrial laser technology in South Korea. He earned his master’s and bachelor’s degrees in electrical engineering from Seoul National University.

Sung is the latest Korean billionaire to make a fortune from the semiconductor sector. Other billionaires in the country include Kwak Dong Shin of Hanmi Semiconductor, manufacturer of equipment used to make high-bandwidth memory chips; Kim Sang-beom of printed circuit board manufacturer ISU Petasys; and Lee Chae-yoon of Leeno Industrial, which makes parts for semiconductor-testing equipment that checks chips for defects.

© Forbes