Growth of SrTiO3 bulk single crystals using edge-defined film-fed growth and the Czochralski methods

Abstract

Cylindrical SrTiO₃ bulk single crystals with diameters of about 15 mm and lengths between 13 and 50 mm were grown from stoichiometric melts by the edge-defined film fed growth (EFG) method. Typical average etch pit density values are in the range of 1.7–2.0 × 10⁵ cm⁻². Rocking curve measurements revealed FWHM values between 28′′ and 41′′. Suitable conditions for the growth of puck-shaped single crystals were also found for the Czochralski (Cz) method. However, the structural quality was lower as compared to crystals grown by the EFG method. So far pulling SrTiO₃ crystals from the melt using the Czochralski method suffered from growth instabilities like diameter fluctuation, foot formation and subsequent spiraling immediately after the seeding stage. We achieved crystals with diameters up to 42 mm and lengths of 15 mm.