DeepSeek's breakthrough has seemingly enabled China to rapidly narrow the gap with the United States in the AI industry. However, the operation of domestic large models as a whole still relies heavily on NVIDIA chips. Although domestic GPU design capabilities are improving rapidly, as TSMC restricts supplies to mainland China, domestic manufacturing of high-end GPUs has become a key challenge for the development of China's AI industry. In particular, achieving self-reliance in advanced CoWoS packaging processes is especially urgent. At present, mainland China has very limited capacity and relies entirely on imported equipment; this bottleneck severely constrains the progress of domestic AI development. Against this backdrop, the Loong series TCB equipment developed by PrecisioNext, through close collaboration with customers, took the lead in completing CoWoS-L test prototyping for domestic AI chips, achieving the first breakthrough for domestic TCB equipment in the field of AI chip CoWoS packaging.
CoWoS Packaging: The Cornerstone of High-Density Integration for AI Chips
With the explosive growth of large AI models, autonomous driving, and high-performance computing (HPC), traditional chip packaging technologies can no longer meet the demands for compute density and energy efficiency. TSMC's CoWoS (Chip-on-Wafer-on-Substrate) technology, by integrating heterogeneous components such as logic chips, high-bandwidth memory (HBM), and silicon interposers through 3D stacking, has become the "ultimate packaging solution" for AI chips. Its core advantages are:
1. Ultra-high-density interconnection: It uses silicon interposers to achieve micron-scale TSV (through-silicon via) interconnects, increasing wiring density by more than 10 times compared with traditional 2D packaging and overcoming data transmission bottlenecks;
2. Ultimate energy efficiency: The "near-memory computing" architecture between HBM and GPU/ASIC chips reduces data transmission power consumption by 50%, significantly improving energy efficiency;
3. Exceptional heterogeneous integration capability: It breaks through the limitations of traditional packaging, supports hybrid packaging of multiple chips and multiple process nodes (e.g., 7nm logic chips + 40nm silicon interposers), and provides greater freedom for chip design.
TCB Equipment: The Heart and Technological High Ground of CoWoS Packaging
In the CoWoS packaging process, Thermal Compression Bonding (TCB) is the core step that determines yield and performance. Its roles include:
1. Precise interconnection: aligning the chip with the interposer or substrate with micron-level precision, and achieving eutectic bonding of copper pillar bumps (Cu Pillar) through thermal compression;
2. Thermal stress control: balancing chip warpage under high temperature and pressure to avoid microcracks or interfacial delamination;
3. Multilayer stacking: supporting multiple bonding of HBM and logic chips to ensure signal integrity.
TCB equipment used in CoWoS packaging has extremely high precision requirements, typically no less than ±1.5 μm; for next-generation TCB equipment, the precision requirement even reaches sub-micron levels. To achieve stable precision and force control under such strictly controlled temperature and pressure conditions, only a few international semiconductor equipment giants can currently produce TCB equipment, such as ASM Pacific of Singapore, Kulicke & Soffa of the United States, and Hanmi of South Korea. At the same time, as AI chip sizes increase (e.g., NVIDIA’s GB200 chip reaches 130 × 90 mm), equipment must support larger bonding areas, higher precision, simultaneous alignment of multiple chips, and fluxless packaging requirements. Fluxless bonding and adaptive warpage compensation technologies are becoming future trends.
Global CoWoS Market Sees Explosive Growth, with Surging Demand in China Coexisting with Capacity Bottlenecks
According to Yole Développement forecasts, the global CoWoS packaging market exceeded US$3.5 billion in 2023 and will expand rapidly at a compound annual growth rate (CAGR) of 42% over the next three years, with the market expected to exceed US$10 billion by 2026. AI chips account for more than 70% of demand—flagship products such as NVIDIA’s H100/H200 and AMD’s MI300X alone require 1–2 CoWoS interposers per chip, while global AI chip shipments in 2024 are projected to reach 1.5 million units, driving the CoWoS capacity gap to continue widening.
China, as the world’s second-largest AI chip market, is seeing demand for CoWoS packaging rise rapidly: domestically produced AI chips such as Huawei’s Ascend 910B, Cambricon’s Siyuan 590, and Biren’s BR100 have entered the CoWoS mass-production stage, with interposer demand reaching 2–4 pieces per chip; internet giants (such as Baidu and Alibaba) are also accelerating the adoption of CoWoS for their in-house AI chips.
According to estimates, mainland China’s CoWoS packaging market will reach US$800 million in 2024 and is expected to exceed US$2.5 billion in 2026, with an annual growth rate of more than 70%. However, the core bottleneck is that key equipment, including TCB equipment, is 100% dependent on imports, and the United States may include high-end TCB equipment in its semiconductor equipment ban against China, putting capacity expansion plans at risk of being unable to proceed for lack of critical equipment.
The U.S. Ban Forces Localization; TCB Equipment Becomes Key to Breaking the AI Chip Manufacturing Bottleneck
The U.S. Department of Commerce’s Bureau of Industry and Security (BIS) has listed CoWoS-related technologies as a “key area of concern.” If export controls are imposed on TCB equipment, mainland China’s advanced packaging production lines may come to a standstill. For example, ASM Pacific has suspended supplies of TCB-series equipment to some Chinese customers; Besi has implemented “case-by-case review” for LAB equipment supplied to Chinese customers. Against this backdrop, localizing TCB equipment is not only a commercial necessity but also a make-or-break lifeline for the security of the AI chip supply chain.
PrecisioNext — The “Barrier Breaker” of China’s TCB Equipment
As the only company in China with independent R&D and production capabilities for CoWoS-class TCB equipment, PrecisioNext has completely rewritten the role of domestic equipment as a “follower” through its technological breakthroughs. Its Loong series TCB equipment, jointly developed with customers, adopts a self-developed ultra-precision high-temperature nano motion platform and multispectral vision positioning system, achieving ±1 μm chip placement accuracy at 450°C, with heating and cooling rates of 150°C/s and 50°C/s. It supports bonding of extra-large 130 × 130 mm chips and is 25% more efficient than comparable equipment from international peers. The Loong series is compatible with wafer-level (12-inch) and panel-level (620 × 620 mm) packaging and supports full-process technologies such as HBM stacking. The completion of this process test marks that domestic TCB equipment has officially entered a brand-new stage.
Even more promising, PrecisioNext is accelerating the development of next-generation fluxless TCB equipment, aiming to improve accuracy to ±0.3 μm. With the explosive growth of China’s CoWoS capacity, PrecisioNext is expected to capture a significant share of the domestic TCB equipment market by 2026 and become a “Chinese calling card” in the global high-end packaging equipment sector.
