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Materials Science of the three pillars of modern civilization (energy, information, materials), one is the material basis of human civilization. Crystal materials as an important functional materials, widely used in electronic devices, semiconductors, solid-state laser devices and optical instruments instrument industry an important material, at the same time play an important role in experimental solid state physics research. Crystal growth belong to materials science and its development of cutting-edge, is a comprehensive reflection of the chemistry, condensed matter physics, electronics, optics and other disciplines. The main crystal materials include: laser crystal, scintillation crystal, optical crystal, nonlinear optical crystal, photorefractive crystal, acousto-optical crystal, optic crystal, single crystal fiber, sapphire crystal, piezoelectric crystals, super-hard diamond crystal, semiconductor crystals and nano-IOL. Main crystal growth method according to the way of the raw materials in the process of crystal growth can be divided into: crystal growth from solution, the crystal growth of crystal growth from the melt and the hydrothermal method. Optical floating zone method is a kind of melt method of crystal growth. Alpha-Al2O3 crystals doped with different ions show different colors, with high hardness second only to diamond, high-temperature chemical stability, high thermal conductivity in the fields of industrial, decorative, medical equipment, optical play an increasingly important role. The common preparation doped alpha-Al2O3 crystal method: temperature gradient method Doped the Cr 3 ruby ??crystal; flame fusion prepared doped the Ti 3 titanium sapphire crystal; Bridgman growth doped the Ti 3 titanium sapphire; Czochralski to doped the Cr 3 ruby ??crystal. Czochralski method is the most universal of the growing crystal method, but due to the melting point of the alpha-Al2O3 at 2050 oC, ordinary iridium crucible crucible or molybdenum crucible crucible fundamental withstand not so high temperature, if the process of growth of crystals to use an iridium crucible crucible, crucible crucible is oxidized easily Ir inclusions formed in the crystal affect the quality of the crystal. Therefore, no optical floating zone of the crucible is the growth of alpha-Al2O3-based crystal ideal choice. This work uses the optical floating zone Preparation? 6-8 mm, a length of 60-80 mm A: Al2O3 (A = Cr, Fe, Ni) crystal. The crystal growth direction for lt; 001 GT; direction, the X-ray double crystal rocking half-height width as 0.089 o that A: Al2O3 (A = Cr, Fe, Ni) crystal having good crystal quality. This article also discusses the shape and stability of the molten zone, raw bar, temperature distribution, growth rate, rotation speed, the solid-liquid interface shape various effects of A: Al 2 O 3 (A = Cr, Fe, Ni) crystal growth factors. By X-ray, polarized light microscopy, scanning electron microscopy to study the growth of the optical floating zone method A: Al2O3 (A = Cr, Fe, Ni) crystal bubbles, cellular structure, solute tail track and dislocations and other defects. In-depth study of the characteristics of the above-mentioned drawbacks and causes the effective measures to reduce and control defects, optimization of the growth process, improve the quality of the crystals, and A: Al2O3 (A = Cr, Fe, Ni) Spectral properties of the crystal, dielectric The electrical properties were studied.
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