Copper core balls are core interconnect materials for 3D packaging, HBM memory stacking, high-density integration of AI chips and high-end GPUs, and high-performance computing. Their structural stability and excellent electrothermal performance support multi-layer stacking processes and improve system reliability.
3D Packaging: The Structural Foundation for High-Density Stacking
In 3D packaging, multiple chips are vertically stacked within the same package, requiring multiple reflow soldering processes. Traditional solder balls, after melting at high temperatures, are prone to collapse under gravitational pressure, leading to short circuits. Copper core balls, with their copper core melting point of 1083℃, remain solid during reflow soldering at around 250℃, effectively maintaining solder joint gaps, preventing deformation and bridging, and ensuring the stability of the multi-layer structure.
HBM Memory Stacking: The Key Support for Breaking the "Memory Wall"
High-bandwidth memory (HBM) achieves TB/s-level data transfer rates by vertically stacking multiple layers of DRAM chips. This structure places extremely high demands on solder joint reliability. Copper core balls not only ensure the physical spatial stability between the multiple DRAM layers within HBM but also, with their conductivity 5–10 times that of solder balls, significantly reduce current density, suppress electromigration, and extend memory lifespan.
AI Chips: The Preferred Solution for High Power Consumption and High Current Density AI training chips (such as the NVIDIA H100) can consume hundreds of watts during operation, with extremely high local current densities. The high conductivity and thermal conductivity of the copper core spheres help reduce signal latency, improve energy efficiency, and quickly dissipate heat, alleviating hotspot issues. Their advantages in electromigration resistance and shock resistance ensure the stable operation of AI chips under long-term high loads.
High-end GPU Packaging: Enabling High-Performance Graphics and Computing Modern high-end GPUs employ Chiplet design and 2.5D/3D packaging technology to integrate the computing core and HBM memory through a silicon interposer. Copper core balls, serving as the vertical interconnect medium between the chip and the interposer, are not only compatible with existing ball-mounting equipment and reflow processes but also maintain connection reliability during multiple thermal cycles, making them a key component for achieving high-bandwidth, low-latency communication.
