China SiC Coated Graphite Trays Manufacturers, Suppliers, Factory

The development of high-powered blue and UV LEDs has enabled the creation of full-color LED TV displays, as well as white LED automotive and domestic lighting. These LEDs are based on Gallium Nitride, which is deposited on substrate wafers supported by CVD SiC-coated graphite susceptor using the MOCVD process.

Chemical Vapor Deposition (CVD) refers to a process technology where multiple gaseous reactants at varied partial pressures undergo a chemical reaction under specific temperature and pressure conditions. The resulting solid substance deposits on the surface of the substrate material, thereby obtaining the desired thin film. In traditional integrated circuit manufacturing processes, the obtained thin film materials are generally compounds such as oxides, nitrides, carbides, or materials like polycrystalline silicon, amorphous silicon, etc.

The third-generation wide bandgap semiconductor materials, such as Gallium Nitride (GaN) and Silicon Carbide (SiC), are renowned for their exceptional optoelectronic conversion and microwave signal transmission capabilities. These materials meet the demanding requirements of high-frequency, high-temperature, high-power, and radiation-resistant electronic devices. Therefore, they have vast application prospects in new-generation mobile communications, new energy vehicles, smart grids, and LED technologies. The comprehensive development of the third-generation semiconductor industry urgently requires breakthroughs in key core technologies, continual advancement in device design and innovation, and a resolution to import dependencies.

Silicon carbide (SiC) is a material that possesses high bond energy, similar to other hard materials like diamond and cubic boron nitride. However, the high bond energy of SiC makes it difficult to crystallize directly into ingots via traditional melting methods. Therefore, the process of growing silicon carbide crystals involves the use of vapor phase epitaxy technology.

In the high voltage field, particularly for high-voltage devices above 20,000V, the SiC epitaxial technology still faces several challenges. One of the main difficulties is achieving high uniformity, thickness, and doping concentration in the epitaxial layer. For the fabrication of such high-voltage devices, a 200um thick silicon carbide epitaxial wafer with excellent uniformity and concentration is required.

Gallium Nitride (GaN) epitaxial wafer growth is a complex process, often utilizing a two-step method. This method involves several critical stages, including high-temperature baking, buffer layer growth, recrystallization, and annealing. By meticulously controlling the temperature throughout these stages, the two-step growth method effectively prevents wafer warping caused by lattice mismatch or stress, making it the predominant fabrication method for GaN epitaxial wafers globally.