In the current era of rapid development of high-tech manufacturing, ceramic materials are no longer limited to traditional applications. With the upgrading of the semiconductor, energy, automotive and aerospace industries, silicon carbide (SiC), as a new high-performance ceramic material, is becoming the focus of industrial manufacturing and electronic engineering. So, what exactly is silicon carbide crystal? What are its structure, properties and uses? This article will be to good ceramics for your in-depth analysis of the nature of this material and industrial value.

Silicon carbide is a compound formed by covalent bonding of carbon (C) and silicon (Si) atoms. It is a covalent crystal with extremely strong atomic bonds and a highly stable lattice structure. This crystal has both ceramic and semiconductor properties, and is a typical wide-band semiconductor material.

Silicon carbide is not a metal or a polymer compound, but an inorganic non-metallic compound crystal. It is extremely stable chemically and remains structurally intact at high temperatures, high pressures, and in strong corrosive environments. Therefore, silicon carbide plays a key role in traditional ceramics, electronic components, high-temperature equipment and new energy industries.

Silicon carbide has an extremely complex crystal structure. It is not a single crystal type, but a polymorphic material with a variety of crystal forms. There are more than 200 known crystal forms of silicon carbide, the common ones include:

The cellular structure of silicon carbide is based on the tetrahedron, where each silicon atom is surrounded by four carbon atoms, forming a stable sp³ covalent bond structure. This strong bonding gives silicon carbide its extremely high hardness, chemical inertness and thermal conductivity.

If you look at the crystal structure of silicon carbide, you can find that its atomic layers are periodically arranged along the c-axis direction, and different stacking orders form different crystal types. This polymorphism is an important source of the unique physical properties of silicon carbide.

In silicon carbide, silicon (Si) has a +4 valence and carbon (C) has a -4 valence. This valence balance ensures the overall electrical neutrality of the crystal.
The main physical properties of silicon carbide are as follows:

• Hardness: close to 9.5, second only to diamond

• Melting point: approx. 2730°C

• Thermal conductivity: 120-270 W/m-K (higher than most metals)

• Refractive index (n): about 2.6-2.7

• Density: about 3.21 g/cm³

• Resistivity: 10⁵-10⁶ Ω-cm (depending on doping)

• Bandwidth: ~2.3-3.3 eV (varies with crystal type)

Thanks to these properties, silicon carbide exhibits extremely high performance in the areas of electrical insulation, heat dissipation, mechanical wear and high-temperature electronics.

In the semiconductor industry, the significance of silicon carbide is comparable to the revolutionary breakthrough of silicon materials back in the day. As one of the representatives of the third generation of semiconductor materials (the other is gallium nitride GaN), silicon carbide semiconductor has a higher breakdown electric field, better thermal conductivity and higher current-carrying density.

Silicon carbide substrates are single-crystal materials grown by the high-temperature sublimation method or chemical vapor deposition (CVD) technology and are used to make substrates for high-power devices.
Silicon carbide substrates are widely used in the precision manufacturing system of well-designed ceramics:

• MOSFET (Field Effect Transistor)

• IGBT (Insulated Gate Bipolar Transistor)

• Schottky diode

• On-Board Charging Module (OBC)

• High temperature sensing device

Due to the high temperature resistance and high breakdown voltage capability of SiC substrates, it enables stable operation of electronic devices at higher power and smaller size.

Silicon carbide wafers, i.e., thin slices cut, ground, and polished from silicon carbide single-crystal rods, are the core material for semiconductor manufacturing.
The high purity SiC wafers provided by Zhihao Ceramics are equipped with:

• High flatness and low defect density;

• Excellent thermal stability;

• Compatible with existing silicon process equipment.

Applications for silicon carbide wafers include inverters for new energy vehicles, power converters, high-speed motor control systems and high-frequency communication equipment.

Silicon carbide has both structural ceramics and functional ceramics, and its applications span a number of high-tech industrial fields:

As a leading supplier of silicon carbide ceramics, ZhiHao Ceramics provides customers with structural and electronic grade silicon carbide components through high purity powder control, precision sintering technology and CNC precision machining.

In industrial raw materials, silicon carbide is mainly divided into two types: black silicon carbide and green silicon carbide.

Zhihao Ceramics uses high-purity green silicon carbide in technical ceramics for semiconductor substrates, heat dissipation substrates and high-temperature electronic components, ensuring the best balance between thermal conductivity and electrical insulation.

Silicon carbide (SiC) and gallium nitride (GaN) are often compared in the discussion of third-generation semiconductors. Both are broadband semiconductors, but each has different strengths:

To summarize:

• Silicon carbide is more suitable for high voltage and high power occasions (such as new energy vehicles, industrial power supply, avionics);

• Gallium nitride is more suitable for high-frequency and high-speed applications (e.g., 5G communications, radar systems).

Zhihao Ceramics has accumulated extensive manufacturing experience in SiC materials, providing long-term reliable ceramic solutions for high-power electronic systems.

Many beginners mistakenly think that silicon carbide is a polymer compound. In fact, silicon carbide is not a polymer structure, but an inorganic covalent crystal.
It has Si-C covalent bonding for atomic bonding, does not have organic polymer chain structure, and does not contain carbon-hydrogen bonding.
Thus, silicon carbide is a typical non-metallic inorganic compound crystalline material rather than a polymer.

The key to the preparation of silicon carbide powder lies in the purity of raw materials, particle control and sintering atmosphere. To Good Ceramics adopts the following preparation path:

1. Acheson reaction synthesis: SiC crystals are produced by reacting quartz sand with a carbon source in a 2200°C resistance furnace;

2. Chemical vapor deposition (CVD) method: Used to prepare high purity single crystal SiC;

3. Reaction Sintering (RBSiC) process: Carbon powder is reacted with Si powder to produce a dense structure;

4. Hot Pressure Sintering (HPSiC) Technology: Improve grain density, enhance mechanical strength and thermal conductivity.

With its own precision sintering and CNC machining capabilities, Zhihao Ceramics is able to provide customized silicon carbide components, integrating the entire process from structural ceramics to electronic substrates.

With the rise of the electric vehicle and photovoltaic energy storage industries, silicon carbide power devices are at the center of the energy efficiency revolution:

• New Energy Vehicle Inverter: SiC MOSFETs Increase System Efficiency by 3%-5% While Reducing Heat Sink Size;

• Fast charging module: SiC devices with high voltage resistance and high-frequency operation characteristics enhance charging efficiency;

• Photovoltaic inverters: Using SiC devices in 1500V systems significantly reduces power losses;

• Energy Storage System (ESS): SiC supports high-frequency PWM control for faster response time.

ToHo Ceramics' SiC substrates and ceramic packaging materials are widely used in electric vehicle main drive systems and high-voltage control modules, helping customers realize energy-efficient and long-life product goals.

As one of the leading technical ceramics manufacturers in China, ZHIHAO Ceramics has a deep technical accumulation in the preparation and processing of silicon carbide materials:

1. High purity raw material system: choose ultra-fine SiC powder, control impurity content below 0.001%.

2. Precision sintering technology: CIP cold isostatic pressure + vacuum sintering process is adopted to ensure high densification and low porosity.

3. CNC precision machining capability: realizes ±0.002mm dimensional accuracy and processes complex geometries.

4. Surface treatment and coating: Support CMP polishing, electroplating, Ni plating, Au plating and other surface processes.

5. Multi-disciplinary cooperation experience: customized ceramic parts for semiconductor, energy, automotive, medical and other industries.

Zhihao Ceramics' Silicon Carbide product line covers a wide range of categories such as substrate wafers, heat sinks, mechanical parts, and insulating mounts to meet the needs of engineers and purchasers in different application scenarios.

The market for silicon carbide semiconductor devices is expanding rapidly as the world moves toward new energy sources and efficient power conversion. It is expected that by 2030, the SiC power device market will exceed ten billion dollars in size.

In the future, Zhihao Ceramics will continue to focus on high-end manufacturing of silicon carbide ceramics, and promote the integrated development from material research and development to end-use applications.
From silicon carbide wafer manufacturing to high-temperature structural ceramics, ZhiHao Ceramics is providing a solid material foundation for the global high-tech industry with precision processes and reliable performance.

Ready to bring your ceramic designs to life?

Contact Good Ceramics for customized ceramic processing solutions that meet the highest standards for your application.