Doosan Acquires SK Siltron for KRW 2.3 Trillion, Expanding into Semiconductor Wafer Supply Chain
Taylor Wilson
Doosan Group is paying KRW 2.3 trillion for a 70.61% controlling stake in SK Siltron — South Korea's only silicon wafer maker and the world's third-largest supplier. This means → Doosan is extending from back-end testing and packaging into upstream materials, assembling a multi-stage semiconductor play.
What is Doosan actually buying?
SK Siltron is South Korea's sole semiconductor silicon wafer manufacturer and ranks third globally in 12-inch wafers — the foundational "blank disc" on which chips are built.
The company posted roughly KRW 2 trillion in 2025 revenue and about KRW 400 billion in operating profit — a 20% margin, making it a profitable asset.
This reflects structural scarcity: the top five wafer makers hold over 90% of the global market. Assets like this rarely come up for sale.
Why did negotiations take seven months?
Doosan was named preferred bidder in December 2025, yet talks dragged on for roughly seven months.
The holdup: surging AI-semiconductor investment kept pushing wafer-asset valuations higher — the seller had less incentive to close quickly.
The final deal uses an earn-out mechanism to bridge the valuation gap. If SK Siltron's annual EBITDA — earnings before interest, taxes, depreciation and amortization, a measure of cash-generating power — exceeds set thresholds between 2027 and 2034, Doosan pays SK 40% of the excess × its 70.61% stake.
In plain terms = strong performance means Doosan pays more; mediocre performance means the base price stands. Both sides share the risk.
What does Doosan's supply-chain map look like now?
Before this deal, Doosan already covered semiconductor testing (Doosan Tesna), image-sensor packaging (Engion), and copper-clad laminates used in chip packaging and AI server substrates.
Adding SK Siltron fills in the furthest-upstream piece: silicon wafer manufacturing — giving Doosan multi-stage coverage from materials and substrates through to test and packaging.
This means → Doosan moves from "semiconductor services provider" to a full-chain player with front-end materials, and its potential customer list includes Samsung Electronics and SK Hynix.
What other terms are buried in the deal?
If SK Siltron's U.S. silicon carbide (SiC — a high-performance semiconductor material used in EVs and clean energy) business generates proceeds through liquidation or asset sales, SK receives additional payments.
A separate earn-out of up to roughly KRW 70.6 billion kicks in if four designated products pass qualification with a specific customer before June 2029.
Doosan has explicitly said it will not separately list SK Siltron. It plans to set up a dedicated integration task force and is considering restructuring options including a merger.
What does this deal need to prove?
Doosan has set a target of roughly KRW 3 trillion in revenue by 2031 for SK Siltron, projecting annual wafer-business growth above 7%.
For SK Group, the sale is part of a broader portfolio restructuring — freeing capital to concentrate on its AI-semiconductor strategy.
This means → the KRW 3 trillion revenue mark in 2031 is the deal's core proving point. Hitting it validates the supply-chain integration thesis; missing it signals Doosan overpaid for a scarce asset.
Content is for reference only, not financial advice.