Abstract: High-quality gallium oxide (Ga₂O₃) single crystals were grown using the edge-defined film-fed growth method (EFG method), with the radiation heat transfer inside the furnace significantly impacting the temperature field distribution and stress distribution during the crystal growth process. Therefore, this study uses different finite element methods to analyze the three-dimensional thermal field distribution of Ga₂O₃ single crystal growth under three different radiation models, including the Rosseland method, the P1 approximation method, and the discrete ordinates method (DOM). A thermoelastic stress model is used to solve the stress distribution within the crystal under different heat flux conditions. Numerical simulation results indicate significant differences in the thermal field calculations under different radiation models. With the same heating power, the Rosseland radiation model has the smallest temperature gradient at the solid-liquid interface, while DOM has the largest temperature gradient. Under the same heat flux, the DOM radiation model exhibits the highest thermal stress during the early cooling stage, while the Rosseland model shows the highest thermal stress during the final cooling stage. Under varying heat flux conditions, the Rosseland radiation model displays the most significant changes in stress and temperature. This research provides theoretical guidance for the thermal field design in single crystal growth for gallium oxide and other related materials.

Key words: EFG method, gallium oxide, radiation model, thermal field, numerical simulation, stress