THERMAL-ANALYSIS OF RARE-EARTH GALLATES AND ALUMINATES

Dilatometry, high-temperature x-ray diffraction, differential thermal analysis, and differential scanning calorimetry have been performed on LaGaO3, NdGaO3, PrGaO3, SmAlO3, and LaAlO3 single crystals grown by the Czochralski technique. First order phase transitions have been located at 145 °C for LaGaO3 and 785 °C for SmA1O3, and ΔH has been measured for the LaGaO3 transition. Second order transitions have been identified for LaGaO3, PrGaO3, NdGaO3, and LaA1O3. The usefulness of these compounds as substrates for high temperature superconducting films is discussed in terms of thermal expansion matching. © 1990, Materials Research Society. All rights reserved.