In the booming development of the new energy vehicle industry, automotive-grade power semiconductors, as core components of electric vehicle electronic control systems, play a crucial role. They not only determine the power performance, energy efficiency, and safety reliability of electric vehicles, but also directly affect the cost structure and market competitiveness of the entire industry chain. This paper delves into the manufacturing process of automotive-grade power semiconductors and the current status of their industry chain in China, aiming to provide valuable reference for relevant companies and industry observers.
I. Manufacturing Process of Automotive-Grade Power Semiconductors
Automotive-grade power semiconductors mainly include insulated-gate bipolar transistors (IGBTs) and metal-oxide-semiconductor field-effect transistors (MOSFETs), which are crucial for the efficient operation of electric vehicle motor control, battery management, and on-board charging systems. The quality of the manufacturing process directly affects the performance, reliability, and cost of the devices.
Substrate material selection and processing
Automotive-grade power semiconductors are typically manufactured using silicon carbide (SiC) or silicon (Si) as the substrate material. SiC substrates, due to their high thermal conductivity, high breakdown electric field strength, and low loss, are more suitable for high-voltage, high-temperature, and high-frequency operating environments, making them the preferred choice for electric vehicles. Si substrates, on the other hand, maintain a certain market share in low-to-mid-range applications due to their lower cost and more mature technology.
The substrate material processing includes steps such as cleaning, polishing, and etching to ensure surface flatness and cleanliness, laying a good foundation for subsequent epitaxial growth and device fabrication.
Epitaxial growth
Epitaxial growth is the process of forming a high-quality single-crystal thin film on a substrate to construct the active region of a device. For SiC substrates, chemical vapor deposition (CVD) or physical vapor deposition (PVD) techniques are typically used to transform SiC raw materials into single-crystal thin films under precisely controlled temperature and atmosphere conditions. The thickness, doping concentration, and crystal quality of the epitaxial layer are crucial to device performance.
Device manufacturing
Device fabrication includes steps such as photolithography, ion implantation, etching, and metallization. Photolithography is used to form precise patterns on the epitaxial layer; ion implantation is used to adjust the doping concentration inside the device to form the desired electrical properties; etching is used to remove unwanted material to form the three-dimensional structure of the device; and metallization is used to form electrodes and interconnects to enable the device to connect to external circuits.
Packaging and Testing
Packaging is the process of combining a device with protective materials, heat sinks, and other components to form a module that can be used in practical applications. The packaging process must ensure the device's mechanical strength, electrical performance, and thermal performance. Testing verifies the performance of the packaged module, including static parameter testing, dynamic parameter testing, and reliability testing, to ensure that the device meets design requirements.
II. Current Status of China's Automotive-Grade Power Semiconductor Industry Chain
In recent years, with the rapid development of the new energy vehicle industry, the domestic automotive-grade power semiconductor industry chain has gradually improved, forming a complete industry chain from raw materials, manufacturing equipment, epitaxial growth, device manufacturing to packaging and testing.
raw materials
While China has made some progress in SiC substrate materials, it still faces technological bottlenecks and insufficient production capacity. Currently, the mainstream SiC substrate suppliers in the market are still dominated by foreign companies, such as Cree from the United States and II-VI from Japan. Domestic companies such as Shandong Tianyue and Tianke Heda are increasing their R&D efforts to improve product quality and production capacity.
Manufacturing equipment
Semiconductor manufacturing equipment is a crucial link in the industry chain, characterized by high technological barriers and significant R&D investment. While China has made some breakthroughs in core equipment such as lithography machines, etching machines, and thin-film deposition equipment, it still needs to strengthen its independent R&D and innovation capabilities to improve equipment performance and stability.
Epitaxial growth and device fabrication
China has established a certain technological foundation and production capacity in epitaxial growth and device manufacturing. However, compared with international advanced levels, domestic companies still lag behind in product quality, production efficiency, and cost control. Furthermore, the technological accumulation and market competitiveness of domestic companies in the high-end automotive-grade power semiconductor field still need improvement.
Packaging Testing
Packaging and testing is a downstream segment of the industry chain and a key component for device applications. China has established a relatively complete industrial system in packaging and testing, boasting a number of packaging and testing companies with considerable scale and strength. However, with the rapid development of the new energy vehicle market and intensifying competition, domestic packaging and testing companies need to continuously improve their technological level and service quality to meet market demands.
Supply chain collaboration and integration
The coordination and integration among various segments of China's automotive-grade power semiconductor industry chain still need to be strengthened. Currently, cooperation between upstream and downstream companies in the industry chain remains relatively loose, lacking a close-knit industry chain coordination mechanism. In the future, it is necessary to strengthen cooperation and communication among upstream and downstream companies in the industry chain, promote technological innovation and industrial upgrading, and improve the competitiveness and risk resistance of the entire industry chain.
III. Conclusion and Outlook
As a core component of the new energy vehicle industry, automotive-grade power semiconductors directly impact the performance, cost, and market competitiveness of electric vehicles through their manufacturing processes and supply chain development. While China has made some progress in automotive-grade power semiconductor manufacturing processes and the supply chain, it still faces numerous challenges and opportunities. Looking ahead, it is necessary to strengthen technological innovation and independent R&D capabilities to improve product quality and production efficiency; enhance collaboration and integration among upstream and downstream enterprises in the supply chain to promote industrial upgrading and enhance market competitiveness; and simultaneously, pay close attention to international market dynamics and trends, actively participate in international competition and cooperation, and promote the sustainable and healthy development of China's automotive-grade power semiconductor industry.
