Origins of Twinned Microstructures in B_(12)As2 Epilayers Grown on (0001) 6H-SiC and TheirInfluence on Physical Properties

摘要

The defect structure in B_(12)As2 epitaxial layers grown at two different temperatures on (0001)6H-SiC by chemical vapor deposition (CVD) was studied using synchrotron white beam x-raytopography (SWBXT) and high resolution transmission electron microscopy (HRTEM). The observeddifferences in microstructures were correlated with the differences in nucleation at the two growthtemperatures. The effect of the difference in microstructure on macroscopic properties of the B_(12)As2 was illustrated using the example of thermal conductivity which was measured using the 3-ωtechnique. The relationship between the measured thermal conductivity and observed microstructuresis discussed.