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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.

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 basic crystal unit cell of monocrystalline silicon is the zinc blende structure, in which each silicon atom bonds chemically with four neighboring silicon atoms. This structure is also found in monocrystalline carbon diamonds.

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.

In the semiconductor industry, epitaxial layers play a crucial role by forming specific single-crystal thin films atop a wafer substrate, collectively known as epitaxial wafers. Particularly, silicon carbide (SiC) epitaxial layers grown on conductive SiC substrates produce homogenous SiC epitaxial wafers, which are instrumental in the fabrication of power devices such as Schottky diodes, MOSFETs, and IGBTs, with 4H-SiC substrates being the most widely utilized.

Currently, silicon carbide dominates the third generation of semiconductors. In the cost structure of silicon carbide devices, substrates account for 47%, and epitaxy contributes 23%. Together, these two components represent about 70% of the overall manufacturing cost, making them crucial in the silicon carbide device production chain.