Large-size sapphire single crystal (350х540х30 мм
3) are grown by Horizontal Directed Solidification Method (HDSM) in the protective gas atmospheres. The HDSM allows to grow the sapphire crystals of high optical quality and structural perfection in the form of plates with record size, inaccessible to other growth methods (Fig.1). Crystals are used for production wide aperture windows (diameter up to 300 mm, diagonal up to 600 mm) with high mechanical and optical characteristics.
Fig.1. Large-size sapphire single crystals for aerospace engeneering, special technological equipment and light transparent armour.Such a technology allows to obtain sapphire plates with thickness up to 80 mm (Fig.2). At the crystal dimensions 350х170х80 мм
3 this development raises the economical efficiency of the traditional HDSM by more than two times, makes this technology competitive with the Kyropoulos method in the word market of 6-10 inch sapphire substrates for modern micro- and optoelectronics.
Fig.2. Large-size sapphire single crystals with record thickness for the HDSM - 80 mm.