In response to the demands of high-performance computing, AI, 5G, and other applications, the shift towards chiplet and the incorporation of HBM memory has become inevitable for advanced chips. As a result, packaging has transitioned from 2D to 2.5D and 3D formats.

With chip manufacturing advancing towards more advanced process nodes, the model of directly packaging chips using advanced packaging technology from wafer foundries has emerged. However, this approach also signifies that wafer foundries will encroach upon certain aspects of traditional assembly and testing, leading to ongoing discussions about the ‘threat’ to traditional assembly and test firms since TSMC’s entry into advanced packaging in 2011.

But is this perspective accurate?

In fact, traditional assembly and test firms remain competitively positioned. Firstly, numerous electronic products still rely on their diverse traditional packaging techniques. Particularly, with the rapid growth of AIoT, electric vehicles, and drones, the required electronic components often still adopt traditional packaging methods. Secondly, faced with wafer foundries actively entering the advanced packaging domain, traditional assembly and test firms have not been idle, presenting concrete solutions to the challenge.

Advanced Packaging Innovations by Traditional Assembly and Test Firms

Since 2023, AI and AI server trends have rapidly emerged, driving the demand for AI chips. TSMC’s 2.5D advanced packaging technology, known as CoWoS, has played a pivotal role. However, the sudden surge in demand stretched TSMC’s capacity. In response, major traditional assembly and test firms such as ASE and Amkor have demonstrated their technical prowess and have no intention of being absent from this field.

For instance, ASE’s FOCoS technology enables the integration of HBM and ASIC. It restructures multiple chips into a fan-out module, which is then placed on the substrate, achieving the integration of multiple chips. Their FOCoS-Bridge technology, unveiled in May this year, utilizes silicon bridges (Si Bridge) to accomplish 2.5D packaging, bolstering the creation of advanced chips required for applications like AI, data centers, and servers.

Additionally, SPIL, a subsidiary of ASE, offers the FO-EB technology, a powerful integration of logic IC and HBM. As depicted below, this technology eschews silicon interposers, utilizing silicon bridges and redistribution layers (RDL) for connections, similarly capable of 2.5D packaging.

Another major player, Amkor, has not only collaborated with Samsung to develop the H-Cube advanced packaging solution but has also long been involved in ‘CoWoS-like technology.’ Through intermediary layers and through-silicon via (TSV) technology, Amkor can interconnect different chips, also possessing 2.5D advanced packaging capabilities.

China’s major assembly and test firm, Jiangsu Changjiang Electronics Technology (JCET), employs the XDFOI technology, integrating logic ICs with HBM through TSV, RDL, and microbump techniques, aimed at high-performance computing.

Given the recent surge in demand for high-end GPU chips, TSMC’s CoWoS capacity has fallen short, and NVIDIA is actively seeking support from second or even third suppliers. The ASE Group and Amkor have secured partial orders through their packaging technologies. This clearly illustrates that traditional assembly and test firms, even when faced with the entry of wafer foundries into the advanced packaging domain, still possess the capability to compete.

In terms of product types, wafer foundries focus on advanced packaging technology for major players like NVIDIA and AMD. Meanwhile, other products not in the highest-end category still opt for traditional assembly and test firms like ASE, Amkor, and JCET for manufacturing. Overall, with their presence in advanced packaging, as well as a hold on the expanding existing packaging market, traditional assembly and test firms continue to maintain their market competitiveness.

(Photo credit: Amkor)