Silicon carbide (SiC) is an advanced functional material that, due to its outstanding physical and chemical properties, is widely used in various industrial fields. Silicon carbide ceramics and silicon carbide wafers are two typical forms of SiC products. While both are based on silicon carbide, they differ significantly in terms of manufacturing processes, application fields, and performance characteristics. This article explores the distinctions and connections between these two materials and highlights their crucial roles in different industries.

1. Material Form and Manufacturing Process

Silicon carbide ceramics are solid materials formed by sintering silicon carbide powder under high temperature and pressure or using other ceramic processing techniques. These ceramics come in various shapes, such as pipes, components, and plates. The manufacturing of SiC ceramics does not require strict control over crystal structure, as the focus is primarily on mechanical properties and physical shapes.

Silicon carbide wafers, on the other hand, are single-crystal or polycrystalline materials produced using highly precise crystal growth techniques, such as chemical vapor deposition (CVD) or sublimation methods. These wafers have a defined crystal orientation and a high degree of purity, and they are cut, polished, and cleaned to achieve a smooth surface. SiC wafers are widely used in microelectronic devices, especially in applications requiring high precision and excellent electrical performance.

2. Application Fields

Silicon carbide ceramics are primarily used in mechanical and chemical industries. Due to their superior wear resistance, high-temperature stability, and corrosion resistance, SiC ceramics are widely applied in components like pumps, seals, and refractory materials. Their mechanical strength and durability make them ideal for harsh environments, such as high-temperature furnaces and heat exchangers.

In contrast, silicon carbide wafers are mainly used in the electronics and semiconductor industries, especially in power electronics devices operating under high power, high frequency, and high-temperature conditions, such as power modules for electric vehicles, RF devices, and LED chips. Owing to their exceptional electrical performance and thermal conductivity, SiC wafers are gradually replacing traditional silicon wafers in power electronics, driving the development of more efficient devices.

3. Physical Properties and Structure

In terms of physical properties and crystal structure, the differences between silicon carbide ceramics and silicon carbide wafers are notable. Silicon carbide ceramics are typically polycrystalline materials with high hardness and strength, making them suitable for mechanical applications where extreme wear resistance and high-temperature performance are required. The properties of ceramic materials are mainly influenced by particle size, density, and sintering processes.

In contrast, silicon carbide wafers are generally single-crystal materials with well-defined crystal orientations and excellent electrical properties. Their high-performance characteristics in electronic applications, especially under high-temperature and high-voltage conditions, include high electron mobility, breakdown voltage, and thermal conductivity, making them the ideal material for power electronics devices.

4. Electrical Properties

Silicon carbide ceramics are generally not used in power electronics, as their primary focus is on mechanical strength and chemical stability. Although certain SiC ceramics may have some electrical conductivity, their main applications remain in insulating or non-electronic environments.

Silicon carbide wafers, on the other hand, are core materials for power electronic devices, offering outstanding electrical properties such as high electron mobility, low on-resistance, and high breakdown voltage. They can operate under high temperatures, high frequencies, and high power conditions, making them a strong alternative to traditional silicon in industries like electric vehicles, smart grids, and communication equipment.

5. Differences and Connections

Despite their differences in appearance, application, and performance, both silicon carbide ceramics and silicon carbide wafers share common advantages derived from SiC's excellent properties, such as high-temperature resistance, corrosion resistance, and extreme hardness. Silicon carbide ceramics are primarily used in mechanical fields, where mechanical performance and durability are critical, whereas silicon carbide wafers are utilized in high-precision electronic fields, where electrical and thermal performance are paramount.

Both materials are able to withstand harsh working conditions and exhibit exceptional performance in their respective domains. This versatility makes silicon carbide an indispensable material in modern industries, driving technological advancements across various sectors.

Conclusion

Silicon carbide ceramics and silicon carbide wafers represent two major application forms of SiC material. While they differ significantly in terms of manufacturing processes, physical characteristics, and application areas, both leverage the unique properties of silicon carbide. Silicon carbide ceramics, with their excellent wear resistance and corrosion resistance, are widely used in mechanical and chemical industries, whereas silicon carbide wafers, with their superior electrical and thermal performance, have become the core material in electronics and semiconductor industries. As technology continues to advance, silicon carbide materials will play an even more critical role in high-end applications.