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There are two types of epitaxy: homogeneous and heterogeneous. In order to produce SiC devices with specific resistance and other parameters for different applications, the substrate must meet the conditions of epitaxy before production can begin. The quality of the epitaxy affects the device's performance.

Silicon carbide (SiC) has important applications in areas such as power electronics, high-frequency RF devices, and sensors for high-temperature-resistant environments due to its excellent physicochemical properties. However, the slicing operation during SiC wafer processing introduces damages on the surface, which, if left untreated, can expand during the subsequent epitaxial growth process and form epitaxial defects, thus affecting the yield of the device.

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.

In the process of wafer preparation, there are two core links: one is the preparation of the substrate, and the other is the implementation of the epitaxial process. The substrate, a wafer carefully made of semiconductor single crystal material, can be directly put into the wafer manufacturing process as a basis to produce semiconductor devices, or further enhance the performance through the epitaxial process.

In semiconductor manufacturing, the precision and stability of the etching process are paramount. One critical factor in achieving high-quality etching is ensuring that wafers are perfectly flat on the tray during the process.

Semiconductors are materials whose electrical conductivity at room temperature lies between that of insulators and conductors. By introducing impurities, a process known as doping, these materials can become conductors.