Silicon carbide (SiC), as an advanced material with excellent performance, has shown great potential for applications in multiple industrial and high-tech fields due to its wide bandgap, high hardness, high pressure resistance, high temperature resistance, and low thermal expansion coefficient. Its product forms are diverse and widely used, gradually driving technological changes in many industries.
1、 Silicon carbide base materials and abrasives
Silicon carbide materials themselves have two basic varieties, black silicon carbide and green silicon carbide, depending on their purity and crystal structure.
Black silicon carbide contains about 95% SiC and has relatively high toughness. It is mostly used for processing materials with low tensile strength, such as glass, ceramics, stone, refractory materials, cast iron, and non-ferrous metals.
Green silicon carbide contains over 97% SiC and has good self sharpening properties. It is mainly used for processing hard alloys, titanium alloys, and optical glass, as well as for honing cylinder liners and precision grinding high-speed steel cutting tools.
In addition, there is cubic silicon carbide, which is a yellow green crystal produced by a special process. The grinding tool used for its production is particularly suitable for ultra precision machining of bearings.
The Mohs hardness of silicon carbide is as high as 9.5, second only to diamond (10), and it has excellent thermal conductivity and semiconductor properties.
2、 Semiconductors and Electronic Devices
As a third-generation semiconductor material, the importance of silicon carbide in the field of electronic devices is increasingly prominent. Its device preparation requires multiple precision processes such as substrate preparation and epitaxial growth.
1. Silicon carbide substrate: According to different electrical properties, it is divided into conductive substrate and semi insulating substrate. Conductive substrates are mainly used for manufacturing power devices and are widely used in fields such as vehicle power supplies, DC charging stations, photovoltaic inverters, energy storage converters (PCS), frequency converters, servo motors, etc; Semi insulating substrates are mainly used for RF devices, such as base station power amplifiers, radar systems, etc. Leading domestic and foreign enterprises such as Tianyue Advanced, Tianke Heda, and Jingsheng Electromechanical have been able to mass produce 6-inch and 8-inch substrates, and actively promote the research and mass production of 12 inch substrates.
2. Silicon carbide Schottky diode: It has ultra fast switching speed, ultra-low switching loss, forward voltage drop (Vf) as a temperature characteristic, is easy to parallel, and can withstand higher withstand voltage and larger surge currents. This type of product is widely used in fields such as electric vehicles, consumer electronics, new energy, and rail transit.
3. Silicon carbide MOSFET: As an important switching device, silicon carbide MOSFET has the characteristics of low on resistance, excellent high-temperature performance, and switching speed. The latest generation products using cellular miniaturization technology or trench gate structure have continuously reduced RDS (on) per unit area and chip area. They are widely used in the main drive inverters, OBC (on-board chargers), DCDC converters, as well as photovoltaic inverters, energy storage systems, industrial automation servo drives, and other fields of new energy vehicles.
4. Hybrid SiC Discrete: It adopts a co packaging structure of silicon-based IGBT parallel SiC Schottky diode, which balances cost and dynamic performance, and is applied in energy storage PCS, OBC, UPS/inverters and other scenarios.
5. Silicon carbide power module: To meet the needs of high-power applications, silicon carbide MOSFETs and diodes are also packaged into industrial and automotive grade full silicon carbide power modules for use in high reliability applications.
3、 Sealing and mechanical components
Silicon carbide ceramics are an ideal material for manufacturing sealing rings due to their good chemical corrosion resistance, high strength, high hardness, good wear resistance, low friction coefficient, and high temperature resistance.
Shanghai Debao Seal Co., Ltd. and other suppliers provide various types of silicon carbide sealing rings, including reaction sintered silicon carbide (SJPRB), pressureless sintered silicon carbide (SJPSS), pressureless sintered silicon carbide with graphite (SJPSG), and pressureless sintered silicon carbide with micropores (SJPSP). These sealing rings of different material types can meet the sealing requirements of different working conditions.
Especially in the petrochemical industry, silicon carbide sealing ring products can effectively cope with the corrosiveness of petrochemical media, ensuring safe and stable production.
The silicon carbide sealing ring for split type sealing adopts professional split technology, which has obvious advantages in installation efficiency and practicality, especially suitable for sealing installation of equipment such as garbage incinerators and large pump valves.
4、 Optics and Emerging Applications
The new application areas of silicon carbide materials are also constantly expanding, especially in the fields of optics and consumer electronics.
Silicon carbide AR glasses lenses: With the high refractive index and high thermal conductivity of silicon carbide materials, silicon carbide optical substrates systematically solve the problems of narrow field of view, rainbow patterns, and heat dissipation faced by traditional AR glasses. In theory, single-layer silicon carbide lenses can achieve a full-color field of view angle of over 80 °, while glass lenses need to be stacked with 3 layers to reach 40 °. This greatly reduces the overall weight of AR glasses and is expected to break through the 20g critical point, approaching the shape of ordinary glasses. Tianke Heda, Shanxi Tiancheng Semiconductor, Yangfan Semiconductor and other enterprises have all laid out in this field.
Heat sink material: Silicon carbide has good thermal conductivity and can also be used as a heat sink material in situations that require efficient heat dissipation.
The silicon carbide product system is rich, from basic abrasives to high-end semiconductor devices, from industrial seals to cutting-edge AR eyeglass lenses. Its applications have almost penetrated into every corner of industrial manufacturing and high-tech industries. With the continuous advancement of preparation technology, especially the improvement of mass production capacity and continuous cost optimization of large-sized substrates (such as 8 inches and 12 inches), silicon carbide products will also play a key role in more fields such as new energy vehicles, renewable energy, 5G communication, artificial intelligence, etc., helping the global industry's green low-carbon and digital transformation.
The silicon carbide industry, especially in the semiconductor field, is currently dominated by overseas giants, but domestic companies such as Tianyue Advanced, Tianke Heda, Jingsheng Electromechanical, Sanan Optoelectronics, etc. are striving to catch up and occupy a place in the global market. In the future, with the continuous innovation of technology and the deepening of application scenarios, the types and performance of silicon carbide products will be further enriched and improved.
