Silicon Carbide (SiC) is an IV-IV group compound semiconductor material formed by covalent bonds between silicon (Si) and carbon (C). It is rare in nature (moissanite is its natural form) and is usually prepared through artificial synthesis (such as the Acheson method, CVD method). It has a variety of crystal structures, including cubic phase (3C-SiC), hexagonal phase (4H-SiC, 6H-SiC), among which 4H-SiC has become the mainstream commercial material due to its excellent electrical properties.
Silicon carbide combines wide gap, high breakdown field strength, and high thermal conductivity, which is significantly superior to conventional silicon (Si) and gallium arsenide (GaAs) :
Properties | SiC (4H type) | Silicon (Si) | Advantage Comparison |
Bandgap width (eV) | 3.2 | 1.1 | Heat resistance, radiation resistance, low leakage current |
Breakdown field strength (MV/cm) | 2.5 3.5 | 0.3 | The device is resistant to high voltage and smaller in size |
Thermal conductivity (W/cm·K) | 4.9 | 1.5 | Strong heat dissipation, suitable for high-power scenarios |
Electron saturation drift velocity | 2.0×10⁷ cm/s | 1.0×10⁷ cm/s | High frequency working ability (up to GHz) |
Maximum operating temperature (° C) | 600 + | 150-200. | Extreme environments applicable (such as aerospace, military industry) |
Other features:
l Chemical inertness: Resistant to corrosion and oxidation, suitable for harsh environments.
l Mechanical hardness: 9.5 on the Mohs scale (second only to diamond), used in wear-resistant materials.
The unique properties of silicon carbide make it irreplaceable in high-power, high-temperature, high-frequency scenarios:
l Power devices:
¢ SiC MOSFET: Replacing silicon-based IGBTs in electric vehicle inverters (such as Electric vehicle Model 3) and photovoltaic inverters, reducing energy consumption by more than 20%.
¢ SiC diode (Schottky barrier diode, SBD) : Fast recovery, low switching loss, for power conversion (such as 5G base station power).
l Voltage rating: covering 600V - 10kV, suitable for smart grids, high-speed rail traction systems.
l 5G communications: sic-based gallium nitride (GaN-on-SiC) power amplifiers to enhance base station signal efficiency.
l Radar/satellite communications: High frequency and high-temperature stability superior to gallium arsenide (GaAs).
l Electric drive system: SiC inverters increase range by 5% to 10% (such as BYD e-Platform 3.0).
l Charging stations: Enable 800V high voltage fast charging (like the Porsche Taycan can charge to 80% in 15 minutes).
l Pv/Wind: SiC converters improve power generation efficiency (>99%).
l Industrial motors: Reduce heat dissipation requirements and save more than 30 percent of energy.
l Aerospace: Radiation-resistant devices for satellite power systems.
l Wear-resistant materials: Cutting tools, bulletproof armor (such as SiC ceramic composites).
l Challenges: High cost (difficult substrate preparation), complex process (high-temperature epitaxy required).
l Prospects: With 6-inch / 8-inch substrates mass-produced and costs falling, the market size of SiC power devices is expected to exceed $10 billion by 2027.
Summary: SiC is a key material in the "post-Moore era," driving green and efficient energy, transportation, and communications.
Phone
+86 13714130672
Address
Room 1505, Senye Chuangda Building Gushu 2nd Road, Xixiang Street Bao'an District, Shenzhen China
