Differences between 3C SiC, 4H SiC, and 6H SiC
May 01, 2024
Silicon carbide (SiC) wafers are usually single crystals, but these single crystal SiC wafers may be composed of different polycrystalline forms, including 3C SiC, 4H SiC, 6H SiC, etc. Each polycrystalline form has its own unique properties.
3C-SiC has a cubic structure
4H-SiC has a tetragonal structure
6H-SiC has a double hexagonal structure
Their differences in the atomic arrangement pattern and coordination number. 3C-SiC has the highest theoretical electron speed, but also has the largest impurity corrosion traces.
4H-SiC and 6H-SiC have better cost-effectiveness and equipment reliability.
3C-SiC has a cubic crystal structure, with each silicon atom surrounded by four carbon atoms and four adjacent silicon atoms. This structure has the highest theoretical electron speed, but is also susceptible to impurities, leading to impurity corrosion marks.
4H-SiC and 6H-SiC both belong to the hexagonal crystal system. Their atomic arrangements are different, but both have better cost-effectiveness and equipment reliability because their crystal structure has better stability and lower impurity concentrations, allowing them to operate at high temperatures,high power and high voltage conditions.