China semiconductor component Manufacturers, Suppliers, Factory

Chemical Vapor Deposition (CVD) is a versatile technique for producing high-quality coatings with various applications in industries such as aerospace, electronics, and materials science. CVD-SiC coatings are known for their exceptional properties, including high temperature resistance, mechanical strength, and excellent corrosion resistance.

SiC's own characteristics determine its single crystal growth is more difficult. Due to the absence of Si:C=1:1 liquid phase at atmospheric pressure, the more mature growth process adopted by the mainstream of the semiconductor industry can not be used to grow the more mature growth method-straight pulling method, the descending crucible method and other methods for growth. After theoretical calculations, only when the pressure is greater than 105 atm and the temperature is higher than 3200 ℃, can we get the stoichiometric ratio of Si:C = 1:1 solution. pvt method is currently one of the more mainstream methods.

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.

The Silicon Carbide (SiC) production process encompasses the preparation of substrate and epitaxy from the materials side, followed by chip design and manufacturing, device packaging, and finally, distribution to downstream application markets. Among these stages, substrate material processing is the most challenging aspect of the SiC industry. SiC substrates are both hard and brittle, making cutting, grinding, and polishing extremely difficult. This increases the likelihood of defects during processing and reduces the yield rate. Currently, major international SiC manufacturers are planning to transition from 6-inch to 8-inch SiC wafers. Overcoming the challenges associated with 8-inch substrates has become a critical benchmark for the SiC industry. This article will introduce the key parameters of SiC substrates.

Defect-free epitaxial growth occurs when one crystal lattice has nearly identical lattice constants to another. Growth happens when lattice sites of the two lattices at the interface region are approximately matched, which is possible with a small lattice mismatch (less than 0.1%). This approximate matching is achieved even with elastic strain at the interface, where each atom is slightly displaced from its original position in the boundary layer. While a small amount of strain is tolerable for thin layers and even desirable for quantum well lasers, the strain energy stored in the crystal is generally lowered by the formation of misfit dislocations, which involve a missing row of atoms in one lattice.