The Czochralski (Cz) technique under an argon/oxygen atmosphere has been used to grow 35 mm diameter La₃Ga_5.5Ta_0.5O₁₄ langatate (LGT) crystals along the Z-axis. Addition of an afterheater is proposed to improve the growth and crystal properties. Two furnace configurations, without and with an afterheater, are investigated experimentally and numerically. A global model for the entire furnace was used in investigating the mechanism of flow, heat transfer, melt–crystal interface shape and 3-d thermal stress considering the crystal anisotropy. Addition of the afterheater changes considerably the thermal field in the growth atmosphere. A decrease of 56% of the maximum von Mises stress and 30% of the interface convexity are found through the use of the afterheater. Experimentally, a more stable growth has been achieved and this resulted in a good quality crystal.

中文翻译：

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添加主动后热器对Czochralski法生长镧系（La ₃ Ga _5.5 Ta _0.5 O ₁₄）晶体的 实验和数值影响

氩气/氧气气氛下的Czochralski（Cz）技术已被用来沿Z方向生长直径35 mm的La ₃ Ga _5.5 Ta _0.5 O ₁₄ langateate（LGT）晶体。-轴。建议添加后热器以改善生长和晶体性能。通过实验和数值研究了两种带和不带后热器的熔炉配置。考虑到晶体各向异性，整个炉子的整体模型用于研究流动，传热，熔体-晶体界面形状和3-d热应力的机理。添加后热器会大大改变生长气氛中的热场。通过使用后加热器，发现最大冯·米塞斯应力降低了56％，界面凸度降低了30％。在实验上，已经实现了更稳定的生长，这产生了高质量的晶体。