Three-petal Graphite Crucible

Semixlab's Three-petal Graphite Crucible is designed specifically for advanced Czochralski (CZ) single-crystal silicon growth systems. Its superior thermal stability, structural integrity, and material purity directly impact crystal quality and production yield.

In the CZ process, polycrystalline silicon melts in a quartz crucible at temperatures above 1420°C, while the surrounding graphite crucible and hot zone components provide mechanical support and define the thermal environment. The stability of the graphite structure is crucial: it controls the radial and axial temperature gradients, influences melt convection behavior, and ultimately determines the shape of the solid-liquid interface during crystal growth. Even minute structural distortions or stress-induced deformations can lead to fluctuations in crystal diameter, changes in oxygen concentration, and increased defect density.

The Three-petal Graphite Crucible employs a segmented structure, dividing the crucible body into three precision-machined sections. This design aims to mitigate circumferential thermal stresses generated during prolonged high-temperature operation and repeated thermal cycling. Unlike traditional monolithic graphite crucibles, which can accumulate stress along the entire ring structure, the three-part structure allows for controlled expansion and stress redistribution at specific interfaces. The result is improved dimensional stability, reduced cracking risk, and enhanced long-term reliability in CZ furnace environments.

From a thermal engineering perspective, maintaining a stable and symmetrical temperature field is crucial for controlling melt flow patterns and the curvature of crystal growth interfaces. Three-petal Graphite Crucible improves radial thermal equilibrium by minimizing deformation and maintaining geometric consistency throughout the growth cycle. This contributes to stable crystal pulling conditions, more precise diameter control, and more uniform oxygen infiltration into the silicon melt from the quartz crucible. This thermal stability is particularly important in the production of large-diameter ingots, which typically have more complex temperature gradients and significantly higher mechanical loads.

Material purity and structural density are equally critical for semiconductor-grade graphite components. Three-petal Graphite Crucible is manufactured using high-density, fine-grained isostatically pressed graphite with strictly controlled impurity content to reduce the risk of metal contamination within the crystal growth cavity. Advanced processing techniques ensure tight dimensional tolerances and precise fit between segments, maintaining mechanical alignment and minimizing heat leakage at interfaces. Depending on the specific process environment requirements, Semixlab can also integrate surface protective coatings (SiC coating, TAC coating, Pyrolytic Carbon Coating) to enhance oxidation resistance and extend lifespan.

Semixlab's Three-petal Graphite Crucible is a reliable product technology support for modern CZ single-crystal silicon manufacturing. Meanwhile, Semixlab is committed to providing leading technologies and customized product solutions for semiconductor crystal growth processes. We sincerely look forward to becoming your long-term partner in China.