TSMC Expected to Stick with Microbumps Over Hybrid Bonding for HBM Packaging

According to media reports, TSMC is expected to continue using its existing microbump packaging technology for advanced packaging that integrates high-bandwidth memory (HBM) with AI accelerators in the near term, rather than transitioning to hybrid bonding. The primary reason is that the industry has been reluctant to abandon a process that is already proven in terms of yield, inspection, and high-volume manufacturing. Given the development cycle for related materials, finer-pitch microbumps are expected to remain in use through the later stages of HBM4 and into the early phase of HBM5. It is reported that TSMC has asked its material and equipment partners to develop 5-micrometer-class bonding and underfill technologies, as part of efforts to further reduce the size of microbumps currently used in advanced packaging. Korean and Japanese suppliers have begun development, with mass production of 5μm-class bumps estimated to begin in the second half of 2028.