In May 2026, South Korean conglomerate Doosan announced the acquisition of a 100% stake in SK Siltron. The total deal value is reported at approximately KRW 5 trillion (around JPY 330 billion). This is not just a large domestic Korean M&A deal; it is a trigger for reassessing SiC wafer supply stability and supplier pricing power.
SK Siltron is a global manufacturer holding the third-largest share in the wafer market. While silicon wafers remain its core business, the company has made a serious push into SiC (silicon carbide) wafers and has been recognized as a key material supplier for power semiconductors used in EVs and industrial equipment. At the same time, the acquisition process has surfaced impairment losses, operating losses, and change-of-control covenant risk in the SiC business.
For procurement and design teams, the key question is whether SiC investment at SK Siltron continues under Doosan, or whether financial constraints slow supply expansion. Companies adopting SiC devices need to evaluate not only device makers but also upstream wafer suppliers' ownership structure, financial health, and long-term supply commitments.
The True State of the SiC Business Comes to Light
The acquisition negotiations have brought to light a serious deterioration in SiC business profitability.
SiC Impairment Loss
KRW 414 billion. Of this, KRW 334 billion in goodwill was written down to zero.
SiC Business Operating Loss
An operating loss of KRW 214.5 billion. Compared to the silicon wafer segment's operating profit of KRW 407.6 billion, the profitability gap between the two businesses is stark.
Interest-Bearing Debt and Covenants
Of total borrowings of KRW 2.7 trillion, approximately KRW 1.2 trillion carries covenants requiring immediate repayment upon a change of shareholder, creating a substantial post-acquisition financial burden.
Focus of Price Negotiations
According to the Seoul Economic Daily, Doosan is seeking a reduction from the originally proposed acquisition price, citing the scale of SiC business losses and contingent liabilities.
The pattern of a profitable silicon wafer business offsetting comparably sized losses in the SiC segment is not unique to SK Siltron. It reflects a broader reality: the plateau in SiC device demand for EVs that began in the second half of 2023 has propagated all the way up to wafer suppliers.
Doosan's Vision for Vertical Integration
Doosan's interest in SK Siltron goes beyond simple asset acquisition. The company already operates in inspection and packaging (back-end processes for wafers), printed circuit boards (CCL), and industrial robotics. Adding SK Siltron would allow Doosan to build a fully vertically integrated supply chain from wafer manufacturing to finished components. The strategy places the chip business at the core and draws materials, equipment, and back-end processes toward it.
The Japan-Korea Supply Chain Cooperation Context
This move coincides with the Japan-Korea joint statement on supply chain resilience announced on May 19. Against a backdrop of renewed government-level confirmation of Japan-Korea cooperation in semiconductor materials and components, South Korea's domestic consolidation in the critical wafer materials segment is underway.
How SK Siltron under Doosan reestablishes cost competitiveness in SiC wafers — a segment where competition with Japanese manufacturers may emerge — will directly shape the industry landscape going forward.
Update: SK Siltron exits the SiC business (July 2026)
In July 2026, this picture moved toward a conclusion. According to media reports such as The Elec, SK Siltron will liquidate its U.S. SiC-wafer subsidiary, “SK Siltron CSS,” within 2026. Losses in the SiC business reportedly widened amid slower EV-market growth and oversupply, with consolidated net loss for 2025 reaching about KRW 293.6 billion. SK Siltron entered SiC in 2019 by acquiring DuPont’s SiC-wafer business for USD 450 million, but is now set to exit after about six years.
Behind the exit is a return to its core silicon-wafer business. Media reports say SK Siltron will expand 300mm silicon-wafer capacity by about 50% through operation of its fourth Gumi plant, a KRW 2.3 trillion investment, and concentrate resources on advanced silicon wafers supported by AI-chip demand. Doosan’s discussions to acquire the silicon-wafer business are also said to proceed on the premise that this loss-making unit is separated. The geopolitics of SiC have shifted the supply structure again, with a major Korean player leaving SiC-wafer supply.
Implications for Management, Procurement, and Design
The figures from this deal suggest that monetizing SiC operations takes longer than most market entrants expect. The pace of EV demand growth, aggressive pricing from Chinese competitors, and manufacturing yield challenges — these factors combined are forcing even major wafer manufacturers to absorb substantial impairment charges.
At the same time, Doosan's acquisition of SK Siltron signals that reliable wafer supply sources may undergo further consolidation. For executives and professionals in corporate planning, procurement, and design who are adopting or evaluating SiC devices, the financial health of wafer suppliers and shifts in their ownership structures are worth tracking as procurement risk factors.
Ongoing capacity, impairment, supply-agreement, and wafer-scaling moves across major suppliers are tracked in our Power Semiconductor Supply & Capacity Tracker (CSV/JSON available).