VCS (Vertical Copper Post Stack) for on-Device AI Memory Solution

With the advancement of on-device AI, we have developed a new memory package platform by applying copper post to meet the growing demand for high-bandwidth memory. The development of a new PR material and process optimization were conducted to achieve fine-pitch Cu posts and plate posts on a stepped structure. In this study, we replaced wire bonding with $\mathbf{C u}$ post in conventional memory design. The fabricated memory demonstrated appropriate warpage behavior and robust reliability. Furthermore, compared to traditional wire bonding, this approach enables finer pitch and wide I/O implementation. As the number of I/O increases, it exhibits significantly higher productivity than wire bonding, making it a suitable structure for the future development of memory technology.