According to a report from Taiwan’s Commercial Times, NVIDIA is aggressively establishing a non-TSMC CoWoS supply chain. Sources in the supply chain reveal that UMC is proactively expanding silicon interposer capacity, doubling it in advance, and now planning to further increase production by over two times. The monthly capacity for silicon interposers will surge from the current 3 kwpm (thousand wafers per month) to 10 kwpm, potentially aligning its capacity with TSMC’s next year, significantly alleviating the supply strain in the CoWoS process.

A prior report from Nomura Securities highlighted NVIDIA’s efforts since the end of Q2 this year to construct a non-TSMC supply chain. Key players include UMC for wafer fabrication, Amkor and SPIL for packaging and testing. NVIDIA aims to add suppliers to meet the surging demand for CoWoS solutions.

The pivotal challenge in expanding CoWoS production lies in insufficient silicon interposer supply. In the future, UMC will provide the silicon interposers for front-end CoW process, while Amkor and SPLI will take charge of the back-end WoS packaging. These collaborations will establish a non-TSMC CoWoS supply chain.

UMC states its current silicon interposer capacity stands at 3 kwpm. However, the company has decided to undertake a one-fold expansion at its Singaporean plant, targeting a capacity of around 6 kwpm. The additional capacity is anticipated to be progressively operational within 6 to 9 months, with the earliest projections for the first quarter of next year.

Yet, due to persistent robust market demand, it’s expected that even with UMC’s capacity expansion to 6 kwpm, it may not completely meet market needs. Consequently, industry sources suggest UMC has opted to further amplify silicon interposer capacity to 10 kwpm, aiming for a two-fold acceleration of production expansion. Addressing these expansion rumors, UMC affirms that growth in advanced packaging demand is an inherent trend and future focus, asserting their evaluation of capacity options and not ruling out the possibility of continuous enlargement of silicon interposer capabilities.

(Photo credit: Amkor)

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)

According to a report by Taiwan’s Commercial Times, JPMorgan’s latest analysis reveals that AI demand will remain robust in the second half of the year. Encouragingly, TSMC’s CoWoS capacity expansion progress is set to exceed expectations, with production capacity projected to reach 28,000 to 30,000 wafers per month by the end of next year.

The trajectory of CoWoS capacity expansion is anticipated to accelerate notably in the latter half of 2024. This trend isn’t limited to TSMC alone; other players outside the TSMC are also actively expanding their CoWoS-like production capabilities to meet the soaring demands of AI applications.

Gokul Hariharan, Head of Research for JPMorgan Taiwan, highlighted that industry surveys indicate strong and unabated AI demand in the latter half of the year. Shortages amounting to 20% to 30% are observed with CoWoS capacity being a key bottleneck and high-bandwidth memory (HBM) also facing supply shortages.

JPMorgan’s estimates indicate that Nvidia will account for 60% of the overall CoWoS demand in 2023. TSMC is expected to produce around 1.8 to 1.9 million sets of H100 chips, followed by significant demand from Broadcom, AWS’ Inferentia chips, and Xilinx. Looking ahead to 2024, TSMC’s continuous capacity expansion is projected to supply Nvidia with approximately 4.1 to 4.2 million sets of H100 chips.

Apart from TSMC’s proactive expansion of CoWoS capacity, Hariharan predicts that other assembly and test facilities are also accelerating their expansion of CoWoS-like capacities.

For instance, UMC is preparing to have a monthly capacity of 5,000 to 6,000 wafers for the interposer layer by the latter half of 2024. Amkor is expected to provide a certain capacity for chip-on-wafer stacking technology, and ASE Group will offer chip-on-substrate bonding capacity. However, these additional capacities might face challenges in ramping up production for the latest products like H100, potentially focusing more on older-generation products like A100 and A800.

(Photo credit: TSMC)

AI Chips and High-Performance Computing (HPC) have been continuously shaking up the entire supply chain, with CoWoS packaging technology being the latest area to experience the tremors.

In the previous piece, “HBM and 2.5D Packaging: the Essential Backbone Behind AI Server,” we discovered that the leading AI chip players, Nvidia and AMD, have been dedicated users of TSMC’s CoWoS technology. Much of the groundbreaking tech used in their flagship product series – such as Nvidia’s A100 and H100, and AMD’s Instinct MI250X and MI300 – have their roots in TSMC’s CoWoS tech.

However, with AI’s exponential growth, chip demand from not just Nvidia and AMD has skyrocketed, but other giants like Google and Amazon are also catching up in the AI field, bringing an onslaught of chip demand. The surge of orders is already testing the limits of TSMC’s CoWoS capacity. While TSMC is planning to increase its production in the latter half of 2023, there’s a snag – the lead time of the packaging equipment is proving to be a bottleneck, severely curtailing the pace of this necessary capacity expansion.

Nvidia Shakes the foundation of the CoWoS Supply Chain

In these times of booming demand, maintaining a stable supply is viewed as the primary goal for chipmakers, including Nvidia. While TSMC is struggling to keep up with customer needs, other chipmakers are starting to tweak their outsourcing strategies, moving towards a more diversified supply chain model. This shift is now opening opportunities for other foundries and OSATs.

Interestingly, in this reshuffling of the supply chain, UMC (United Microelectronics Corporation) is reportedly becoming one of Nvidia’s key partners in the interposer sector for the first time, with plans for capacity expansion on the horizon.

From a technical viewpoint, interposer has always been the cornerstone of TSMC’s CoWoS process and technology progression. As the interposer area enlarges, it allows for more memory stack particles and core components to be integrated. This is crucial for increasingly complex multi-chip designs, underscoring Nvidia’s intention to support UMC as a backup resource to safeguard supply continuity.

Meanwhile, as Nvidia secures production capacity, it is observed that the two leading OSAT companies, Amkor and SPIL (as part of ASE), are establishing themselves in the Chip-on-Wafer (CoW) and Wafer-on-Substrate (WoS) processes.

The ASE Group is no stranger to the 2.5D packaging arena. It unveiled its proprietary 2.5D packaging tech as early as 2017, a technology capable of integrating core computational elements and High Bandwidth Memory (HBM) onto the silicon interposer. This approach was once utilized in AMD’s MI200 series server GPU. Also under the ASE Group umbrella, SPIL boasts unique Fan-Out Embedded Bridge (FO-EB) technology. Bypassing silicon interposers, the platform leverages silicon bridges and redistribution layers (RDL) for integration, which provides ASE another competitive edge.

Could Samsung’s Turnkey Service Break New Ground?

In the shifting landscape of the supply chain, the Samsung Device Solutions division’s turnkey service, spanning from foundry operations to Advanced Package (AVP), stands out as an emerging player that can’t be ignored.

After its 2018 split, Samsung Foundry started taking orders beyond System LSI for business stability. In 2023, the AVP department, initially serving Samsung’s memory and foundry businesses, has also expanded its reach to external clients.

Our research indicates that Samsung’s AVP division is making aggressive strides into the AI field. Currently in active talks with key customers in the U.S. and China, Samsung is positioning its foundry-to-packaging turnkey solutions and standalone advanced packaging processes as viable, mature options.

In terms of technology roadmap, Samsung has invested significantly in 2.5D packaging R&D. Mirroring TSMC, the company launched two 2.5D packaging technologies in 2021: the I-Cube4, capable of integrating four HBM stacks and one core component onto a silicon interposer, and the H-Cube, designed to extend packaging area by integrating HDI PCB beneath the ABF substrate, primarily for designs incorporating six or more HBM stack particles.

Besides, recognizing Japan’s dominance in packaging materials and technologies, Samsung recently launched a R&D center there to swiftly upscale its AVP business.

Given all these circumstances, it seems to be only a matter of time before Samsung carves out its own significant share in the AI chip market. Despite TSMC’s industry dominance and pivotal role in AI chip advancements, the rising demand for advanced packaging is set to undeniably reshape supply chain dynamics and the future of the semiconductor industry.

(Source: Nvidia)

According to TrendForce research, driven by strong demand for 5G mobile phones, base stations, automobiles, and HPCs, the global output value of packaging and testing (including foundry and IDM) reached US$82.139 billion in 2021, or 25.83% YoY. This upward momentum is forecast to continue in 2022, taking output value to US$101.185 billion in 2022, or 23.19% YoY. From the perspective of regional distribution, China’s IC packaging and testing output value in 2021 was approximately US$39.443 billion, increasing 31.7% compared with US$29.941 billion in 2020, becoming the world’s fastest-growing major market in terms of packaging and testing output value.

Shanghai pandemic lengthens overall lead time, hinders China’s packaging and testing growth in 2Q22

In 2Q22, Shanghai was locked down due to the COVID-19 pandemic. Although wafer fabs and packaging and testing plants were still operating normally, the pandemic hindered logistics and the materials required for packaging could not be effectively shipped from Shanghai, affecting transportation efficiency and logistics costs to a certain degree. Overall, China’s packaging and testing industry was not significantly affected by the pandemic in 1Q22 but, in 2Q22, the industry will bear the brunt of the COVID-19 situation, with packaging and testing companies experiencing prolonged overall lead times and sluggish revenue growth.

NEVs and HPCs to become new growth drivers, fabs and packaging and testing companies accelerate deployment

The growth rate of smartphones, a core driving force behind IC packaging and testing output value, is slowing down. Since smartphone shipments peaked at 14.575 million units in 2017, volume has not surpassed this number in the ensuing years. Even though the upgrade from 4G to 5G brought about a wave of replacements, the overall smartphone market has reached maturity, with slowing growth or even negative growth, so its demand on wafer manufacturing and packaging and testing is likewise slowing down.

Aside from mobile phones, growth in HPC and new energy vehicles (NEV) is becoming a new revenue engine. At present, the world’s major automobile production countries are accelerating the penetration rate of NEVs, and packaging and testing companies are also accelerating their investment in the automotive and HPC sectors. From the perspective of fabs, TSMC’s HPC revenue accounted for 41% of total packaging and testing revenue in 1Q22, surpassing mobile phones for the first time and becoming the largest source of the company’s packaging and testing revenue.

（Image credit: Unsplash）