Changes in the solid-liquid interface during the growth of Bi12SiO20, Bi12GeO20 and LiNbO3 crystals grown by the Czochralski method

Control of Intrinsic Defects in Lithium Niobate Single Crystal for Optoelectronic Applications

“…A nearly flat solid-liquid interface was ensured in order to have a high quality crystal [72] as a non-flat interface leads to highly strained regions near the core of the crystal and results in the generation of extended defects like dislocations, low-angle grain boundaries, cracks etc. in the crystal [72].…”

“…To avoid composition variation which arises due to a gradual increase in the Li content in the remaining melt during the growth process, crystals with weight less than 5% of the total starting melt were pulled. A nearly flat solid-liquid interface was ensured in order to have a high quality crystal [72] as a non-flat interface leads to highly strained regions near the core of the crystal and results in the generation of extended defects like dislocations, low-angle grain boundaries, cracks etc. in the crystal [72].…”

“…A nearly flat solid-liquid interface was ensured in order to have a high quality crystal [72] as a non-flat interface leads to highly strained regions near the core of the crystal and results in the generation of extended defects like dislocations, low-angle grain boundaries, cracks etc. in the crystal [72]. Similarly, nSLN crystals (nSLN_K) were also grown using K2O as solvent with similar growth conditions and parameters except for the rotation rates, which were marginally higher (20-5 rpm) in this case (Figure 3b).…”

Numerical Study on LiCaAlF<SUB>6</SUB> Czochralski Crystal Growth

“…Non-flat interface could be the principal reason for the generation of dislocations and consequently for many undesirable effects such as inhomogeneous distribution of impurities, strains, cracks, low-angle grain boundaries, gas bubble entrapment, facet etc. [4][5][6][7][8][9][10][11][12][13][14][22][23][24] At the melt-crystal interface, latent heat Q L is released during solidification and appears as a source term in the energy balance at the solidification interface as…”

“…The inversion (from convex to concave) of the interface shape is often taken as a critical condition experimentally, and the desirability of a flat interface has motivated theoretical, numerical and experimental investigations on the hydrodynamics of melt associated with the shape of the crystal-melt interface. [4][5][6][7][8][9][10][11][12][13][14] To date, many reports of the critical conditions for the flat interface and the inversion of interface shape have been published in the literature, but most of these studies have focused on the oxide rather than fluoride crystal. Because of the complex growth conditions and non-linear phenomena in the crystal growth process, the optimal parameters of crystal growth for different materials and growth conditions are difficult to be obtained by an empirical formulation or other simple ways.…”