Silicon Carbide Susceptor

SiC-Coated Graphite: Graphite core with a coating of silicon carbide is quite possibly the most general susceptor design. The SiC coating provides an extremely clean, hard, and chemically inert surface that renders the susceptor extremely resistant to wear and service life.
Pure Graphite (Carbon): Some susceptors are made of pure graphite alone. Graphite has very high melting points and very good thermal homogeneity. It can oxidize or lose particles in reactive atmospheres, however, and so will tend to require a protective coating.
Quartz (Fused Silica): Quartz susceptors or wafer boats are utilized in ultra-clean processes, such as diffusion furnaces and oxidation/annealing steps. Fused silica is extremely pure (99.99%+ SiO₂)​ and supports about 1000–1200 ℃.
Metal (for instance, Molybdenum): Metal susceptors are used in certain reactors and RTPs. Molybdenum has excellent thermal conductivity and can be machined to precision, and hence it can be used in single-wafer MOCVD reactors and a few RTP systems. Metals can withstand extremely high temperatures, but they must be used under non-oxidizing conditions so as to avoid corrosion.

The lifespan of a susceptor depends on materials and process conditions, but all are consumables over time. In clean, mild environments, they can last hundreds of cycles. In harsh settings like GaN MOCVD, wear or deposits may require earlier replacement. SiC-coated graphite susceptors last longer than uncoated ones due to better corrosion and wear resistance. Quartz susceptors are also durable but must be replaced if devitrification or cracks appear. Regular maintenance, like cleaning and avoiding thermal shock, helps extend service life.

Pricing for wafer susceptors from Newthink varies depending on size, material (such as quartz, graphite, or SiC-coated), design complexity, and precision requirements. Since susceptors are high-precision components, Newthink provides customized quotes based on customer specifications and current material prices.
For single-piece orders used in R&D or as replacements, higher unit costs should be expected. Bulk orders can lower the price per unit.

SiC susceptors offer superior high-temperature strength, thermal conductivity and longevity compared to both quartz and graphite. SiC maintains its strength at temperatures up to 1600℃. Quartz softens above 1100℃ and leads to instability. SiC susceptor also has a higher thermal conductivity, bringing faster and uniform heating. Moreover, for its thermal shock resistance and wear resistance, SiC lasts significantly longer than quartz.

Yes. SiC ceramics have remarkable thermal cycling resistance, withstanding rapid temperature changes without cracking based on its high thermal conductivity. SiC ceramic susceptor retains strength at high temperatures. It is able to maintain its structural stiffness even after repeated thermal cycling. Its ability to sustain extreme temperatures and temperature flux without rapid deterioration is ideal for thermal applications with high reliability.

The lifespan of a silicon carbide susceptor depends on temperature, mechanical stress and operation quality.
When used close to or above its design temperature, oxidation speed increases, increasing the resistance and contributing to aging. The environment contributes to the processes, as oxidizing gases create an oxidizing effect on the surface. Other considerations include poor installation and excessive surface loads that generate thermal and mechanical stresses which can produce cracking and reduced life.