An investigation into the ordering of metal atoms in CuGaS_2 grown by MOVPE

摘要

The ordering of metal atoms in the A~Ⅰ-B~Ⅲ-C_2~Ⅵ ternary semiconductor CuGaS_2 is investigated. X-ray diffraction spectra obtained from epilayers grown by metalorganic vapour-phase epitaxy with a varying [Cu]/[Ga] ratio resembled those expected for epilayers with the chalcopyrite structure, orientated with the c-axis perpendicular the (001) GaAs substrate. Transmission electron diffraction patterns taken along the equivalent cubic < 211 > zone-axes, however, revealed the presence of disordered zincblende material present for the bulk of the epilayer. The chalcopyrite crystal structure is likely present in the form of surface crystallites.