TSMC is preparing to enter the next phase of memory innovation with HBM4 (High Bandwidth Memory Gen 4), marking a major leap in both interface width and packaging sophistication. HBM4 doubles the interface from 1024 bits to 2048 bits, setting a new standard for high-performance computing and AI workloads. This shift demands more advanced packaging and manufacturing technologies—an area where TSMC is positioning itself as a clear leader.
🧩 Advanced Base Die Fabrication #
At the 2024 European Technology Symposium, TSMC unveiled details of its upcoming HBM4 base dies, which will be produced using logic processes rather than traditional memory processes. The company plans to utilize both N12FFC+ (12nm FinFET Compact Plus) and N5 (5nm) nodes, offering distinct performance and cost advantages.
- N12FFC+: A cost-effective 12nm-class process derived from TSMC’s 16nm platform, ideal for building high-density HBM4 stacks with strong performance.
- N5: A cutting-edge 5nm logic node, offering higher integration, lower power consumption, and support for direct 3D stacking.
TSMC’s Senior Director of Design and Technology Platform stated that the company is collaborating with major HBM partners—including Micron, Samsung, and SK Hynix—to accelerate the development and integration of HBM4 using advanced logic-based base dies.
“Base dies manufactured on the N12FFC+ process meet HBM performance and cost targets, while N5 base dies maintain HBM4 speeds, add complex logic, and significantly cut power,”
— TSMC Senior Director of Design & Technology Platform
⚙️ CoWoS-L and CoWoS-R Optimization #
TSMC is also enhancing its CoWoS-L and CoWoS-R packaging technologies to handle HBM4’s expanded interface and interconnect density. These platforms now feature:
- 8+ routing layers to maintain signal integrity across 2,000+ interconnects
- Massive interposer areas—up to 8× reticle size—accommodating up to 12 HBM4 stacks
- Data rates of 6GT/s at approximately 14mA current
Such configurations support 12-Hi (48GB) and 16-Hi (64GB) HBM4 stacks, achieving aggregate bandwidths beyond 2TB/s per stack.
To ensure robust signal and thermal performance, TSMC is working closely with EDA vendors like Cadence, Synopsys, and Ansys for verification of signal integrity, IR drop, electromigration, and thermal accuracy in HBM4 channels.
🚀 Toward Direct 3D Bonding #
For the most advanced configurations, TSMC’s N5 base dies will enable direct 3D bonding between HBM4 and logic dies. With an interconnect pitch of 6–9μm, this approach eliminates traditional interposers, allowing HBM4 memory stacks to be directly integrated atop compute dies. This leap in vertical integration offers:
- Higher bandwidth
- Lower latency
- Reduced power draw
- Smaller form factors for AI and HPC processors
Such integration will be vital for next-generation AI accelerators and HPC chips that rely on massive memory throughput.
🤝 Industry Collaboration #
TSMC is already partnering with SK Hynix on early HBM4 base die production, and it may also manufacture base dies for Micron. Samsung, which operates its own advanced logic fabs, is less likely to collaborate in this area. Nonetheless, TSMC’s combination of advanced nodes and packaging leadership places it at the forefront of the HBM4 supply chain—a critical foundation for future AI and HPC innovation.
Summary:
TSMC’s dual-node strategy—leveraging N12FFC+ for cost efficiency and N5 for advanced integration—positions it as the key enabler of HBM4 memory. Combined with CoWoS-L/R packaging, direct bonding, and 3D integration, TSMC is paving the way for the next generation of AI and high-performance computing systems.