China silicon nitride machining Manufacturers, Suppliers, Factory

The history of silicon carbide (SiC) dates back to 1891, when Edward Goodrich Acheson accidentally discovered it while attempting to synthesize artificial diamonds. Acheson heated a mixture of clay (aluminosilicate) and powdered coke (carbon) in an electric furnace. Instead of the expected diamonds, he obtained a bright green crystal adhering to the carbon. This crystal had a hardness second only to diamond, and was thus named carborundum. In 1904, French-Jewish chemist Henri Moissan discovered rare natural silicon carbide minerals while studying meteorite samples from the Diablo Canyon in Arizona, USA. He named these minerals moissanite, and his discovery earned him the 1906 Nobel Prize in Chemistry.

Silicon Carbide (SiC) has emerged as a key material in the field of semiconductor technology, offering exceptional properties that make it highly desirable for various electronic and optoelectronic applications. The production of high-quality SiC single crystals is crucial for advancing the capabilities of devices such as power electronics, LEDs, and high-frequency devices. In this article, we delve into the significance of porous graphite in the Physical Vapor Transport (PVT) method for 4H-SiC single crystal growth.

Gallium oxide (Ga2O3) as an "ultra-wide bandgap semiconductor" material has garnered sustained attention. Ultra-wide bandgap semiconductors fall under the category of "fourth-generation semiconductors," and in comparison to third-generation semiconductors such as silicon carbide (SiC) and gallium nitride (GaN), gallium oxide boasts a bandgap width of 4.9eV, surpassing silicon carbide's 3.2eV and gallium nitride's 3.39eV. A wider bandgap implies that electrons require more energy to transition from the valence band to the conduction band, endowing gallium oxide with characteristics like high voltage resistance, high-temperature tolerance, high power capability, and radiation resistance.

A SiC boat, short for silicon carbide boat, is a high-temperature-resistant accessory used in furnace tubes to carry wafers during high-temperature processing. Due to the outstanding properties of silicon carbide such as resistance to high temperatures, chemical corrosion, and excellent thermal stability, SiC boats are extensively utilized in various thermal treatment processes including diffusion, oxidation, Chemical Vapor Deposition (CVD), and annealing.

In the process of growing SiC and AlN single crystals by the physical vapor transport method (PVT), components such as the crucible, seed crystal holder and guide ring play a vital role. During the preparation process of SiC, the seed crystal is located in a relatively low temperature region, while the raw material is in a high temperature region exceeding 2400°C. The raw materials decompose at high temperatures to form SiXCy (including Si, SiC₂, Si₂C and other components).

SiC substrate can have microscopic defects, such as Threading Screw Dislocation (TSD), Threading Edge Dislocation (TED), Base Plane Dislocation (BPD), and others. These defects are caused by deviations in the arrangement of atoms at the atomic level.