8-nti SiC coated graphite nplhaib rau SiC Epitaxy

Material and Physical Characteristics

Semixlab’s SiC coated graphite ring is fabricated from isostatic graphite as the base material, followed by a uniform chemical vapor deposition (CVD) SiC coating. This unique structure provides a balance of strength, precision, and resistance to harsh process conditions.

Applications in SiC Epitaxy Process

In the SiC epitaxial growth process, the SiC coated graphite ring serves as a structural and functional interface component between the wafer, susceptor, and other graphite parts inside the MOCVD or CVD reaction chamber. Its performance directly influences epitaxial layer quality, film uniformity, and overall reactor stability — all critical parameters for high-yield SiC power device fabrication.

1. Wafer Support and Alignment

The graphite ring is precisely machined to ensure accurate wafer centering and secure placement during high-temperature epitaxial deposition. Its dimensional stability under thermal load maintains the correct wafer alignment and prevents edge warping, ensuring consistent layer growth across the wafer surface.

2. Uniform Thermal Distribution

During SiC epitaxy, maintaining a uniform temperature gradient across the entire wafer is essential to achieve consistent film thickness and doping concentration. The SiC coated ring assists in thermal load balancing by improving heat transfer between the susceptor and wafer edge region, reducing hot spots and ensuring uniform epitaxial layer formation even at elevated temperatures exceeding 1600°C.

3. Process Environment Protection

Uncoated graphite components are susceptible to chemical erosion and particle emission in reactive epitaxial atmospheres containing gases like H₂, SiH₄, and C₃H₈. The CVD SiC coating on the ring acts as a protective barrier, isolating the graphite substrate from corrosive gases, thus minimizing impurity contamination and preventing carbon-based particles from entering the growth zone. This results in improved wafer surface cleanliness and higher device yield.

4. Reduction of Edge Effects and Gas Flow Optimization

In advanced 8-inch SiC epitaxy systems, edge uniformity is often a key process challenge. The SiC coated graphite ring helps stabilize laminar gas flow near the wafer edge, preventing turbulent zones and ensuring a controlled boundary layer environment. This optimized gas flow distribution contributes to improved edge epitaxial thickness control, reducing material waste and ensuring high-quality layer deposition even on large-diameter wafers.

5. Compatibility with Multiple Reactor Designs

Semixlab’s SiC coated graphite rings are designed for compatibility with major epitaxy equipment brands such as AIXTRON, Veeco, and LPE. The rings can be customized in geometry, coating thickness, and interface structure to precisely match reactor-specific susceptor assemblies, enabling seamless integration and stable performance across different epitaxial platforms.

6. Extended Component Lifetime and Process Reliability

Through the combination of isostatic graphite’s high mechanical strength and CVD SiC’s exceptional wear resistance, the coated ring exhibits outstanding durability under long-term cyclic operation. It resists microcracking, chemical corrosion, and thermal fatigue, ensuring stable performance over extended process cycles, thereby reducing maintenance frequency and operational costs in high-volume epitaxy production lines.

Cov txiaj ntsig ntawm Semixlab

With over two decades of expertise in semiconductor epitaxy and advanced ceramic coating technologies, Semixlab provides comprehensive solutions for high-purity SiC components.

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●Custom Manufacturing:Tailored sizes, coating thickness, and geometry according to specific reactor designs(AIXTRON,Veeco,LPE, etc.).

●Sample Support: Rapid prototyping and sample service available for evaluation and process validation.

●Technical Consultation: Experienced engineers provide pre-sales and process integration advice to optimize performance and longevity.

●Quality Assurance: Each component undergoes precise inspection, coating thickness measurement, and high-temperature testing before delivery.