Dongwu Securities: AI computing power drives silicon capacitors to take advantage

The Zhitong Finance App learned that Dongwu Securities released a research report saying that silicon capacitors use monocrystalline silicon as a substrate and are manufactured through semiconductor processes such as thin film deposition, lithography, and deep silicon etching. They have significant advantages in high-frequency, high-temperature, ultra-thin, and high-reliability scenarios, and form a complementary division of labor rather than an alternative relationship with MLCC. The bank pointed out that the iteration of AI chips/HBM packages and 800G/1.6T optical modules is driving the industrialization of silicon capacitors to accelerate, and the global market size is expected to increase from US$1.07 billion in 2024 to US$1.82 billion in 2031, and CAGR of about 8% in 2024-2031.

The main views of Dongwu Securities are as follows:

Silicon Capacitors: Reshaping Passive Component Performance Boundaries with Semiconductor Processes

There are three main silicon capacitor routes in the industry: planar (planar), deep groove (DTC), and through hole integration (VIC). The planar structure process is the most mature. It forms a capacitor based on an electrode plate. The structure is simple, the capacity density is limited, and the thickness is normal, and it is used in traditional or low-end scenarios. The DTC process is mature. By etching deep grooves with a high aspect ratio and depositing medium and electrode materials on the side wall, the effective area is greatly increased. The volume density is high, and the thickness is less than 40 μm. It is used in high-performance mainstream applications such as AI servers and high-speed optical modules. The industrialization of VIC is in an accelerated phase. It has higher capacity density, has the potential for further thinning and integration, and is more suitable for GPU near-chip power supply and high-end advanced packaging. MLCC and silicon capacitors have a complementary division of labor rather than an alternative relationship: MLCC uses low-cost, high-capacity board-level general filtering and voltage regulation; silicon capacitors specialize in high-end scenarios such as near-die decoupling within packages with advantages such as ultra-low ESL, ultra-thinness, and high-frequency stability. Especially in AI servers, board-level MLCCs are limited by parasitic inductance, and silicon capacitors are closely attached to the chip to ensure package-level power integrity. The two work together at various levels to meet general and extreme requirements, respectively.

Driven by AI industry trends, silicon capacitors are expected to usher in broad room for growth

1) AI chip/HBM package: With an ESL of less than 10 pH and a thickness of less than 40 μm, silicon capacitors are expected to gradually become standard components in GPU, ASIC, and HBM packages due to their core value of near-die decoupling within the package. Industrial signals are already highly concentrated: Samsung Electric has signed a long-term silicon capacitor supply contract worth about 1.5 trillion won (about 6.8 billion yuan) with a major global company, officially starting the large-scale commercial phase of this business; the Nvidia Rubin architecture has included embedded silicon capacitors as standard. 2) High-speed optical module: 800G/1.6T optical module iteration places higher demands on signal integrity and high-frequency filtering. With extremely low high-frequency insertion loss and temperature resistance above 200°C, silicon capacitors play a key role in optical module power supply filtering and signal coupling. According to QYResearch data, the global silicon capacitor market size is about 1.07 billion US dollars in 2024, the global silicon capacitor market will reach 1.82 billion US dollars in 2031, and the CAGR in 2024-2031 is about 8%.

Silicon capacitors are still in the early stages of industrialization, and the market competition pattern is concentrated

The silicon capacitor industry has both semiconductors and passive components. Cross-border integration makes R&D and mass production extremely difficult. In addition, products directly affect chip reliability, and the customer verification cycle is long, making it difficult for new players to enter on a large scale in the short term. The competitive pattern in the global silicon capacitor market is concentrated. Major overseas manufacturers include Murata, Rohm Semiconductors, and Samsung Electric. On the domestic side, most of the listed companies such as Torch Electronics, Hongyuan Electronics, Fenghua Hi-Tech, and HTC Electronics are in the development or cultivation stage; while unlisted companies such as Sunar Optoelectronics, Langsi Technology, and Lingcun Technology have received orders from leading customers or achieved large-scale mass production and delivery, and the products have entered the AI chip and optical module supply chain.

Risk Alerts

The industrialization process falls short of expected risks; downstream market demand falls short of expected risks; customer verification and introduction fall short of expected risks; industry competition increases risks.