Doosan's board on July 31 approved a share purchase agreement to buy SK's 70.6% stake in SK Siltron for 2.3 trillion won — a large deal that makes Doosan the company's new owner.

Korea's only wafer maker

Founded in 1983, SK Siltron is the country's only semiconductor wafer manufacturer. It makes 300mm (12-inch) and 200mm (8-inch) silicon wafers and is rated among the global top three in 12-inch wafers. A wafer is the base on which chips are etched, so stable supply at the materials stage feeds directly into finished-product competitiveness.

Doosan already runs semiconductor back-end (test and packaging) operations, so the deal gives it vertical integration from front-end materials to back-end packaging. It set a 2031 revenue target of about 3 trillion won for SK Siltron, citing a stable earnings base and higher shareholder value.

Why wafers, why now

As the AI boom lifts chip demand, the value of the underlying materials is rising alongside finished products. Advanced chips require high-quality, large-diameter wafers, a market shared among a handful of global players. Doosan's entry also carries meaning for the materials self-sufficiency of Korea's chip ecosystem.

For seller SK, the sale reads as a move to free up liquidity and focus on core businesses. The buyer's and seller's calculations lined up to seal the deal.

Where it touches Sinophone business

A reshuffle in chip-materials supply chains is not remote from Chinese-owned firms trading in electronics and components worldwide, since where wafer supply concentrates can shift downstream partners and prices. Still, large M&A must clear regulatory review and integration before real effects show.

A third perspective

Hwagyo Sibo does not frame this deal as one firm's win or loss. Competition over chip materials is a stage where Korea, China, Taiwan and the U.S. move by different calculations. We lean on no single forecast; we place the announced terms beside the regulatory and market reactions that follow, so readers can judge for themselves.