Epitaxial Growth and Characterization of Silicon Carbide

Silicon carbide (SiC) is a wide-bandgap semiconductor renowned for its exceptional thermal conductivity, high breakdown electric field and radiation hardness. Its various polytypes, notably hexagonal 4H-SiC and cubic 3C-SiC, underpin applications in high-temperature electronics, power conversion and optoelectronics. Epitaxial growth techniques such as chemical vapour deposition and solution growth enable the deposition of thin, device-quality SiC layers on native or foreign substrates. Controlling parameters like temperature, pressure, gas composition and substrate orientation is critical to minimise extended defects—stacking faults, threading dislocations and basal plane dislocations—which degrade device performance. Advanced characterisation methods, including high-resolution X-ray diffraction, photoluminescence imaging and non-destructive three-dimensional microscopy, provide insight into defect formation, impurity incorporation and crystal quality. Recent advances in in situ monitoring and machine learning–enhanced analysis are refining our understanding of nucleation, growth kinetics and defect evolution. By integrating growth optimisation with precise characterisation, the field is progressing towards wafer-scale, low-defect SiC substrates that will underpin the next generation of energy-efficient power electronics and harsh-environment sensors.

Research from Nature Portfolio

Recent studies have demonstrated that epitaxial cubic SiC layers grown on silicon retain excellent rectifying characteristics after high-temperature annealing up to 1100 °C, confirming the thermal stability of the heterojunction under typical device processing conditions. The work showed that diode leakage currents and ideality factors remain within acceptable ranges, indicating that defect-related degradation is localised rather than systemic. Another foundational contribution introduced a surface-exchange model for nitrogen incorporation during vapour phase epitaxy of 4H-SiC. This framework attributes dopant incorporation trends to transient carbon vacancies at the growth surface, driven by hydrogen etching, and explains the influence of growth parameters—C/Si ratio, temperature and pressure—on nitrogen incorporation without invoking reactor-specific effects.

Epitaxial Growth and Characterization of Silicon Carbide publication trend

The graph below shows the total number of articles in epitaxial growth and characterization of silicon carbide across all publications each year (not limited to Nature Index journals).

Technical terms

Epitaxy: The ordered growth of a crystalline layer on a substrate, maintaining crystallographic orientation across the interface.

Polytype: A variant crystal structure of SiC distinguished by different stacking sequences of Si–C bilayers, such as 4H, 6H or 3C.

Heterojunction: The interface formed between two dissimilar semiconductor materials, here between SiC and silicon or between different SiC polytypes.

Stacking fault: A planar defect where the normal sequence of atomic planes is disrupted, often serving as sites for electrical leakage.

Threading screw dislocation: A line defect that threads through the crystal, characterised by a helical displacement of atomic planes along its axis.

Basal plane dislocation: A defect lying in the basal crystallographic plane, which can expand under stress to form stacking faults.

Rocking curve: A measure in X-ray diffraction of crystal mosaicity, given by the full width at half maximum of the diffraction peak.

Micro-CT scanning: A non-destructive imaging technique using X-rays to reconstruct three-dimensional internal structures at micrometre resolution.

References

1. Research progress of large size SiC single crystal materials and devices. Light: Science & Applications (2023).
2. High‐Quality and Wafer‐Scale Cubic Silicon Carbide Single Crystals. Energy & Environmental Materials (2023).
3. Non‐destructive and deep learning‐enhanced characterization of 4H‐SiC material. Aggregate (2024).
4. Excellent Rectifying Properties of the n-3C-SiC/p-Si Heterojunction Subjected to High Temperature Annealing for Electronics, MEMS, and LED Applications. Scientific Reports (2017).
5. A new model for in situ nitrogen incorporation into 4H-SiC during epitaxy. Scientific Reports (2017).