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Tongfu Microelectronics packages and tests computer chips for other companies, putting the fragile silicon into protective shells and checking that it works.
Tongfu Microelectronics does the unglamorous but essential work at the end of the chip-making line: it takes bare silicon chips made by other companies and turns them into finished parts that can be soldered onto circuit boards. This is called packaging and testing. The bare chip is tiny and fragile, and it has to be wrapped in a protective case, wired up so it can talk to the rest of the electronics, and then checked to make sure it actually works before it ships. Tongfu runs factories that do all of this at huge scale for customers in phones, communications gear, cars, AI systems, and home appliances.
The company is based in Nantong, China, and was formerly named Nantong Fujitsu Microelectronics. That old name hints at how it got started: it was a joint venture with Fujitsu, the Japanese electronics giant, before it grew into a large independent player. Today it is one of the biggest chip-assembly and test companies in China, which puts it in a small club of firms that sit between the chip designers and the gadget makers. Here is the basic problem Tongfu solves. A chip company like Advanced Micro Devices can design a powerful processor, but designing it is only half the job. Someone has to physically build it, and that means two separate specialists: a foundry like Taiwan Semiconductor Manufacturing that etches the circuits onto silicon wafers, and a packager like Tongfu that cuts the wafer into individual chips, mounts each one in a protective package, connects it to the outside world, and stress-tests it for heat, speed, and reliability. Customers pick Tongfu because packaging is hard to do well at scale and getting it wrong means dead chips and wasted money.
Tongfu's big bet has been the advanced packaging used for AI chips, where several chips are stitched together into one powerful unit. It works closely with Advanced Micro Devices — a relationship that dates back to the old Fujitsu joint venture days — and in 2024 agreed to acquire a majority stake in AMD's own chip-packaging and testing plants in Suzhou and Penang, Malaysia. That deal deepens a partnership that already made AMD one of its most important customers. The risk is plain: Tongfu's fortunes are tied to a handful of large customers and to the health of the global chip cycle, while rivals like ASE Technology Holding compete hard on price and technology. The AI boom is the tailwind; a downturn in electronics demand is the headwind.
Saved answer · last researched 15 Nov 2026