The optimal solution in the post-Moore era? How Chiplet Affects the Domestic Chip Industry Chain

The Chiplet technology, which is in the air, is regarded by the industry as possibly the optimal solution after the slowdown of Moore's Law.

Chip giants such as AMD, TSMC, Intel, and Nvidia have entered the market in recent years. Omdia predicts that the global market for new devices using Chiplets in the manufacturing process will expand to $5.8 billion in 2024, a nine-fold increase from $645 million in 2018; by 2035, the market will reach $57 billion.

Many research institutions believe that in the post-Moore era, Chiplet will bring huge development opportunities to China's integrated circuit industry. Wei Shaojun, a professor at Tsinghua University and vice chairman of the China Semiconductor Industry Association, believes that the emergence of Chiplet may make Chinese companies move further downstream in the value chain, "but Chinese companies can make a difference in Chiplets, for example, they can make use of Chiplets. Faster development of applications has prompted Chinese companies to transform to standard core particles."

Low cost is the core advantage of Chiplet

Chiplet, also known as chip or small chip, is a type of die (bare chip) that meets specific functions through die-to-die internal interconnection technology to realize the package of multiple module chips and the underlying basic chip to form a system chip. Implement a new form of IP multiplexing.

At present, the mainstream system-level single-chip (SoC) is to fabricate multiple computing units responsible for different types of computing tasks on the same wafer by lithography. For example, mobile phone SoC chips basically integrate computing units with different functions such as CPU, GPU, DSP, ISP, NPU, Modem, and many interface IPs. They pursue high integration and rely on advanced manufacturing processes.

Compared with SoC, the core advantage of Chiplet is cost, including manufacturing cost and design cost.

First of all, under the huge demand for computing power, the number of chip transistors has increased sharply, and the chip area has also continued to expand. Chiplet design divides large chips into smaller chips, thereby effectively improving yield and reducing the cost increase caused by defective rate. A researcher in the electronics industry of a securities firm told Yicai, "Multi-chip integration under the more advanced process (such as 5nm) has a significant advantage, because in a single-chip system with an area of 800mm2, the additional cost caused by silicon wafer defects accounts for More than 50% of the total manufacturing cost.”

Secondly, the logic computing unit of the SoC chip relies on advanced manufacturing processes to improve performance. Other parts can usually use lower-cost mature manufacturing processes. After the SoC chip is chipletized, different chips can be manufactured separately according to their needs. Advanced packaging technology for assembly, thereby effectively reducing manufacturing costs.

In addition, with the advancement of semiconductor technology, the difficulty and complexity of chip design are also increasing, and the design cost is high. The cost of chip design generally includes EDA software, IP procurement, chip verification and tape-out, related hardware and labor costs, etc. According to IBS statistics, the design cost of each generation of technology after the 22nm process increases by more than 50%. The cost of designing a 28nm SoC chip is about 50 million US dollars, while the 7nm requires 300 million US dollars, and the 3nm design cost may reach 1.5 billion US dollars.

Divide the SoC into several key chiplets, each chiplet can balance R&D costs in more applications, avoid huge losses caused by insufficient shipments after a large SoC chip is designed, thereby shortening the R&D cycle, R&D personnel investment, etc.

The above-mentioned researcher said, "For design companies, chip iterations can be completed in a lower cost and faster design speed. For example, AMD's Ryzen series chips use multi-core methods to achieve the overclocking and cost of Intel products. , the market share has gradually increased in recent years.”

However, there are different views in the industry. Wei Shaojun believes that to develop multiple chips at the same time, the research and development costs must be doubled, and during mass production, the yield of each chip is multiplied, which will lead to a sharp drop in the yield of the final Chiplet product. Assuming that the Chiplet contains 5 chips (chips), and the yield of each chip is 90%, the yield of the product after the integration of 5 chips will drop to 60%.

Wei Shaojun said in an interview with the media that the biggest application of Chiplet is the one that "needs" to adopt heterogeneous integration, such as integrating computing logic with DRAM (dynamic random access memory) to overcome the storage wall; followed by applications with severely limited volume For example, in a mobile phone, multiple core particles are integrated into a cavity through Chiplet to save volume; again, it is used in harsh environments, such as automobiles, industrial control, and the Internet of Things.

Yicai learned from the industry that for a major domestic manufacturer, the Chiplet process can allow them to make breakthroughs in the server main chip, and use 14nm-class CPU cores to achieve performance through quantity stacking and sacrificing volume/heat dissipation/power consumption. It is also possible to use the CPU of the advanced process through the cooperative company, and then make the supporting chips in China to complete the packaging; however, it will not be directly applied to the mobile phone at present, the volume is relatively large, and the power consumption is also very high, so Chiplet needs to be applied to the mobile phone. 3D packaging is required.

Chiplet's impact on the industrial chain

At present, the packaging solutions that can be applied to Chiplets are mainly SIP, 2.5D and 3D packaging. Among them, the development of 2.5D packaging technology has been very mature, and has been widely used in FPGA, CPU, GPU and other chips. 3D packaging technology is more difficult, and it is currently mastered and commercialized by Intel and TSMC. "3D packaging is TSV technology, 2.5D is closer to a two-story small house, 3D is the shape of a building, and the space utilization efficiency is higher." said the above researcher.

"For the industry chain, the current 2.5D chiplet implementation method is mainly beneficial to packaging companies. For example, Tongfu Microelectronics (002156.SZ) packaged for AMD in the past, the value is doubled compared to traditional packaging, and the gross profit margin is also higher." The above-mentioned researcher told Yicai, "The second is the carrier board company, such as Xingsen Technology (002436.SZ). At present, Chiplet's 2.5D process finished chip has a large area and high on-chip communication requirements. With the increase in area demand, Xingsen's ABF carrier board production line can be supported by relatively large orders in the future; then packaging and testing equipment companies, such as Huafeng Measurement and Control (688200.SH), etc."

Tongfu Microelectronics is an important packaging and testing foundry of AMD. It has layout and reserves in Chiplet, WLP, SiP, Fanout, 2.5D, 3D stacking, etc., and now has the large-scale production capacity of Chiplet's advanced packaging technology.

In addition, Changdian Technology (600584.SH) joined the UCIe (Universal Chiplet Interconnect Express) industry alliance in June this year to participate in the standardization of Chiplet interface specifications. According to the Q&A with investors, it launched a full range of XDFOI solutions for extremely high-density fan-out packaging last year, which is an extremely high-density, multi-fan-out packaging high-density heterogeneous integration solution for Chiplets, including 2D/ 2.5D/3DChiplet can provide customers with one-stop service from conventional density to very high density, from very small size to very large size.

The above-mentioned researcher said that IP companies have not yet fully entered the stage of their play. Most of the current chiplet companies focus on self-research, but the industry will continue to specialize in the future, such as VeriSilicon (688521.SH) , Chiplet will be an important driving force for their development in the future.

VeriSilicon recently told Yicai that VeriSilicon has been committed to the advancement of Chiplet technology and industry in recent years. Ecology, Platform as an Ecosystem", promotes the industrialization of Chiplet and further promotes the development of the company's main business.