High-temperature powder X-ray diffraction measurements for ScAlMgO4 (R3¯m in space group) grown by Czochralski method were carried out from 303 to 1473 K. The obtained temperature-dependent unit cell parameters were expressed as La = 0:32489(3) + 1:78(8) × 10-6(T - 273) + 6:2(6) × 10-10(T - 273)2 for the a-axis and Lc = 2:5138(2) + 2:52(5) × 10-5(T - 273) + 5:6(4) × 10-9(T - 273)2 for the c-axis, where T is temperature in kelvin. The axial thermal expansion coefficients for the a-axis estimated from the unit cell parameters were comparable to those of GaN and ZnO. A c-plane ScAlMgO4 substrate can be easily obtained with using cleavage plane along c-plane, which is parallel to a-axis. Thus, ScAlMgO4 is one of the promising substrates for c-plane epitaxial growth of GaN and ZnO. High temperature X-ray single crystal structural analysis of ScAlMgO4 demonstrated the mechanism of the nonlinear variation of the obtained cell parameters as a function of temperature.
ASJC Scopus subject areas
- Physics and Astronomy(all)