The growth and characterization of single crystals using a floating-zone method

Abstract

Single-crystal rods and fibres of of various sizes oriented along [100] direction were successfully produced by a floating-zone method. Each of these crystals has a purely orthorhombic structure and a clear Curie transition at (with a peak at ). Investigation of the growth characteristics revealed that the vaporization of is dependent on the quality of the source rod, the growth rate and the length of the molten zone. For a source rod of pure , a growth rate of and a sufficiently short molten zone (for example 1.7 - 2.0 mm for growth of a 2.8 - 3.2 mm diameter crystal), a good (transparent, without cracks or inclusions) single crystal can be produced directly from the stoichiometric source rod. Otherwise, a source rod with excess is necessary to compensate for the vaporization of during the growth process. The excess amount of required is dependent on the sintered state of the source rod, the growth rate and the phase structures of the original powders from which the source rod had been pressed. In general, an increase in growth rate or in sintering temperature can decrease the required excess amount of in the source rod. However, the excess amount of required can be dramatically decreased by making the source rod from and .

Flux Growth of Pure and Lanthanum (La3+)-Substituted Bi4Ti3O12 Single Crystals and Their Characterization

“…These results indicate that the grown crystals contain c-axis perpendicular to the major crystal surface and aðbÞ axis exists in either one of the side faces. Since the growth direction of BIT is along the a-axis, 19) the longest direction (normal to the c-axis) in our crystal is identified as the a-axis. The grown crystals were subjected to chemical compositional analysis using EDAX.…”

Crystal Growth and Electric Properties of Bismuth Titanate Fibers

“…Furthermore, BIT crystals cleave easily. Large crystals were grown by a lamp-heated floating-zone (Fz) method with laser-assisted heating 9) and a flux method. 10) However, the crystal diameter was still at the millimeter level.…”