Mitsui Kinzoku builds $1.2B Malaysia plant for AI copper foil

Mitsui Kinzoku approved an estimated 190 billion yen ($1.2 billion) investment on Nov. 10, 2026, to construct a high-performance copper foil factory in Malaysia for artificial intelligence hardware substrates.

The capital outlay marks the group's largest materials manufacturing commitment in Southeast Asia. Production lines will target advanced graphics processing units, network switches and optical transceivers, the Japanese metals manufacturer said in a regulatory filing.

Board members approved 144 billion yen for production machinery and other assets. The project also commits 32 billion yen for industrial facilities and 14 billion yen to acquire property adjacent to its existing subsidiary.

The facility will boost output of VSP electrodeposited copper foil by 1,200 metric tons per month. That expansion lifts Mitsui Kinzoku's overall VSP production capacity to 2,600 metric tons per month by fiscal 2032.

VSP foil features an ultra-low profile surface designed to curb high-frequency signal loss in data centers. Shipments will serve multi-layered printed circuit boards inside high-bandwidth network switches, the Tokyo-based company said.

Mitsui Kinzoku plans to add 600 metric tons of monthly VSP capacity in fiscal 2031. A second phase of 600 metric tons will follow in fiscal 2032, according to the board notice.

Management designed the Malaysian plot to accommodate an ultimate output ceiling of 3,600 metric tons monthly. Mitsui Kinzoku said it is evaluating a worldwide VSP operating footprint of 5,000 metric tons.

The new facility will also fabricate MicroThin carrier-supported ultra-thin copper foil. The plant will add four million square meters of monthly MicroThin capacity, raising corporate production volume to 12 million square meters.

MicroThin foil measures between 1.5 and five micrometers in thickness to enable ultra-fine semiconductor circuitry. The foil bonds to rigid carrier sheets to prevent mechanical tearing during package fabrication, the company said.

The roadmap schedules two million square meters of monthly MicroThin capacity in fiscal 2031. An identical two million square meter module is slated to join commercial operations in fiscal 2033, the filing said.

The combined expansion lifts MicroThin production capacity to 2.4 times its fiscal 2025 level. Company-wide VSP foil capacity will expand to 3.6 times baseline levels across the same eight-year strategic timeframe.

Mitsui Kinzoku manufactures both specialty materials through its Engineered Materials business segment. The company projects operating income in its copper foil division will climb 3.2 times by 2030 from fiscal 2025 levels.

Operating profit is targeted to expand 5.5 times by fiscal 2033, the company said. Financial impact on consolidated earnings for the fiscal year ending March 2027 will remain negligible.

Surging demand for flip-chip ball grid array substrates has tightened worldwide ultra-thin foil procurement. Advanced accelerators require large-body packages with dense interconnect layers that consume more specialized foil than standard chips.

Semiconductor packaging fabricators require specialized carrier-peelable foils to prevent signal degradation at fine circuit pitches. Mitsui Kinzoku holds an estimated worldwide market share exceeding 80% in carrier-supported ultra-thin copper foil for package substrates.

Optical transceiver modules deployed in AI clusters also require MicroThin materials to handle high-speed interconnects. Data center operators are upgrading from 800-gigabit transceivers to 1.6-terabit optical hardware, accelerating substrate foil consumption.

Competitor Furukawa Electric is countering with rival capacity additions in East Asia. Furukawa manufactures F0X-WS electrodeposited foil and is expanding production across facilities in Tochigi prefecture, Japan, and Taoyuan, Taiwan.

Building the second plant in Malaysia gives Japanese materials makers insulation from East Asian trade frictions. Packaging substrates manufactured across Southeast Asia can access domestic assembly lines without crossing mainland Chinese customs checkpoints.

The Malaysian operating entity, Mitsui Copper Foil Malaysia Sdn. Bhd., already manages electrodeposited lines in Shah Alam. The expansion anchors core fabrication steps near regional semiconductor packaging hubs in Penang and Singapore.

Contract chip packaging houses and substrate vendors in Southeast Asia have expanded cleanroom capacity since 2024. Mitsui Kinzoku aims to deliver foils directly to these factories without relying on Japanese export routes.

Commercial operations at the new Malaysian plant will begin in phases starting in April 2031. That commissioning date aligns with next-generation accelerator roadmaps planned by major server hardware designers, the company said.

The corporate filing does not state the precise industrial park parcel for the site. Mitsui Kinzoku has also not disclosed the filing schedule for Malaysian environmental clearance permits.