TSMC taps GlobalFoundries to bolster US silicon interposer production in $2B deal

A hole in America's domestic supply chain is closing. US-based wafer-fab GlobalFoundries announced a $2 billion partnership with TSMC on Thursday to shore up American manufacturing of advanced semiconductors, like those used in AI datacenters. Under the multi-year deal, GloFo will produce silicon interposers for TSMC's chip-on-wafer-on-substrate (CoWoS) advanced packaging spec at its Malta, New York fab site. Silicon interposers are essential to the production of many multi-die chip assemblies like GPUs and AI accelerators. These interposers sit under the compute logic and memory and provide a higher speed and lower power path for communications between the chips than would be possible using conventional organic packaging. Basically every chip that employs high-bandwidth memory (HBM) today relies on some form of interposer or interconnect bridge to stitch everything together. GlobalFoundries' partnership with TSMC appears to target the former. Advanced packaging has become a major bottleneck for American chip manufacturing. Notably, when TSMC began producing Nvidia's Blackwell generation of GPUs in its Arizona chip plant last year, we noted that the final product would still need to be round tripped to Taiwan and back for final assembly. TSMC has contracted with Amkor, an outsourced semiconductor assembly and test (OSAT) provider, for CoWoS compatible packaging services in the US and has broken ground on its own advanced packaging facilities in Arizona. However, neither of these facilities is expected to come online until 2028 and 2029 respectively. GlobalFoundries, for its part, plans to add additional capacity at its Malta plant to meet demand, but volume production won't begin until the first half of 2028 at the earliest. The partnership is expected to last five years with the option to extend as needed. While CoWoS packaging remains a bottleneck for America's domestic chipmaking ambitions, it's not the only option, just the most popular. Intel Foundry already offers both leading edge process and advanced packaging tech comparable to TSMC's CoWoS offerings. What's more, this tech is compatible with silicon produced at TSMC fabs. Intel routinely employs chips made by TSMC but packaged in its facilities. Doing so does require designing parts for Intel's packaging, but if making chips in America did become a priority, customers wouldn't necessarily have to wait for TSMC and Amkor's facilities to come online. (R)