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With the global energy transition, the AI revolution, and the wave of new-generation information technologies, silicon carbide (SiC) has rapidly advanced from being a "potential material" to a "strategic foundational material" due to its exceptional physical properties.

In semiconductor high-temperature processes, the handling, supporting, and thermal treatment of wafers rely on a special supporting component—the wafer boat. As process temperatures rise and cleanliness and particle control requirements increase, traditional quartz wafer boats gradually reveal issues such as short service life, high deformation rates, and poor corrosion resistance.

For industrial-scale production of silicon carbide substrates, the success of a single growth run is not the end goal. The real challenge lies in ensuring that crystals grown across different batches, tools, and time periods maintain a high level of consistency and repeatability in quality. In this context, the role of tantalum carbide (TaC) coating goes beyond basic protection—it becomes a key factor in stabilizing the process window and safeguarding product yield.

​Silicon carbide (SiC) PVT growth involves severe thermal cycling (room temperature above 2200 ℃). The enormous thermal stress generated between the coating and the graphite substrate due to the mismatch in coefficients of thermal expansion (CTE) is the core challenge determining coating lifetime and application reliability.

​In the silicon carbide (SiC) PVT crystal growth process, the stability and uniformity of the thermal field directly determine the crystal growth rate, defect density, and material uniformity. As the system boundary, thermal-field components exhibit surface thermophysical properties whose slight fluctuations are dramatically amplified under high-temperature conditions, ultimately leading to instability at the growth interface.

In the process of growing silicon carbide (SiC) crystals via the Physical Vapor Transport (PVT) method, the extreme high temperature of 2000–2500 °C is a “double-edged sword” — while it drives the sublimation and transport of source materials, it also dramatically intensifies impurity release from all materials within the thermal field system, especially trace metallic elements contained in conventional graphite hot-zone components. Once these impurities enter the growth interface, they will directly damage the core quality of the crystal. This is the fundamental reason why tantalum carbide (TaC) coatings have become a “mandatory option” rather than an “optional choice” for PVT crystal growth.