TSMC advances CoPoS packaging at Taoyuan Longtan site

The Longtan Phase 3 restart signals TSMC reclassifying advanced packaging from a support function to a strategic moat. CoPoS shifts interconnect from wafer-level to panel-level, enabling 3-5x larger die-to-die areas per AI accelerator while cutting unit cost roughly 20%, directly pressuring ABF substrate suppliers (Ibiden, Unimicron) and accelerating the glass-substrate transition. The three-year regulatory delay in Taiwan, China exposes structural friction: land-use review cycles now rival construction timelines for mega-fabs. The NDC sign-off elevates AI compute infrastructure to national-engineering status, reducing future approval risk at AP7/AP8. Competitively, Intel Foveros, Samsung HBM4 stacks, and ASE contract packaging face an 18-month window to match panel-level yield or cede the AI accelerator packaging market. The 12-24 month trajectory: CoPoS enters volume ramp by Q2 2026 across the Chiayi-Taoyuan-Tainan triangle, compressing CoWoS capacity premiums and reshaping BOM economics for custom ASIC players (Broadcom, Marvell). Pure-play OSAT models face structural erosion as IDM packaging capability absorbs the value chain vertically.