Crystal Growth Techniques

Czochralski (Cz) and Top Seeded Solution Growth (TSSG) Techniques are used.

Czocharlski LAB is based on a Cyberstar puller with a middle frequency Hüttinger (9.2 kHz) generator.  The growth chamber incorporates an induction coil, and an  insulating set up. It allows the preparation of single crystals under controlled  atmosphere (oxygen and/or inert gas) or in vacuum. The coil hosts Pt and Ir crucibles with 40 mm of diameter and height. Typically crystals with 20 mm of diameter and 50-60 mm of length are grown at a rate ranging from 1 to 2 mm/h. Cz technique is applied to compounds with a congruent melt.

TSSG LAB is based in home-made vertical furnaces with Kantal A1 coils as heater.  TSSG is applied to compounds with incongruent melt or with structural phase transitions, it is also used for liquid phase epitaxy.

Crystals are oriented by X-ray diffraction Laue technique.

Crystals are cut with diamond saw blades and polished to laser grade with two Logitech® LP5 machines.

A SETARAM SETSYS Evolution 16 thermogravimetric and differential scanning calorimeter is used to study phase transitions and melting upon heating from room temperature up to 1500 ºC.

X-ray single crystal and neutron diffraction techniques are used to resolve the crystal structure and to evaluate the occupancy factors of ions sharing the same crystal site.