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We report the growth of bulk β-Ga2O3 crystals based on crystal pulling from a melt using a cold container without employing a precious-metal crucible. Our approach, named oxide crystal growth from cold crucible (OCCC), is a fusion between the skull-melting and Czochralski methods. The absence of an expensive precious-metal crucible makes this a cost-effective crystal growth method, which is a critical factor in the semiconductor industry. An original construction 0.4–0.5 MHz SiC MOSFET transistor generator with power up to 35 kW was used to successfully grow bulk β-Ga2O3 crystals with diameters up to 46 mm. Also, an original diameter control system by generator frequency change was applied. In this preliminary study, the full width at half maximum of the X-ray rocking curve from the obtained β-Ga2O3 crystals with diameters ≤ 46 mm was comparable to those of β-Ga2O3 produced by edge-defined film fed growth. Moreover, as expected, the purity of the obtained crystals was high because only raw material-derived impurities were detected, and contamination from the process, such as insulation and noble metals, was below the detection limit. Our results indicate that the OCCC technique can be used to produce high-purity bulk β-Ga2O3 single crystalline substrate. [ABSTRACT FROM AUTHOR]

Plate shaped Fe-Al alloy crystals were successfully grown using the -PD method. The orientation and grain size could be controlled by using the well oriented Fe0.95Al0.05 seed crystal. The as-grown Fe0.82Al0.18 and Fe0.80Al0.20 showed the magnetostriction 3=2 = 121 and 149 ppm, respectively, which is comparable to the values for single crystal samples grown by the Bridgman-Stockbarger method. Distributions of Fe and Al were homogenous along the growth direction within standard deviations of 0.35% and 1.3%, respectively. A prototype vibration energy harvester was demonstrated using the grown Fe-Al alloys. [ABSTRACT FROM AUTHOR]

Undoped and neodymium-doped (1 at %) gadolinium vanadate (GdVO4) single crystals 5 mm in diameter and up to 25 mm in length, uniform in cross section, have been grown by the micropulling down method. The chemical and phase compositions of the crystals have been determined, and their absorption spectra were measured. [ABSTRACT FROM AUTHOR]

The absorption and luminescence spectra of Yb3+ and the luminescence decay kinetics for the Yb3+2F5/2 level in YVO4:Yb3+ crystals are studied. The luminescence cross section for the Yb3+2F5/2 → 2F7/2 transition in YVO4:Yb3+ is determined by the Füchtbauer–Ladenburg method, and the radiative lifetime of Yb3+ is evaluated. [ABSTRACT FROM AUTHOR]