Structural studies of Cu-III-VI₂ chalcopyrite semiconductor heteroepitaxial films grown by low-pressure metalorganic vapor phase epitaxy

Growth orientation, domain structures, and residual strain of Cu(Al,Ga)(S,Se)₂ epitaxial films grown by low-pressure metalorganic vapor phase epitaxy on various substrates were systematically investigated. All epilayers grew in such a manner that the lattice mismatch between the epilayer and the substrate became minimum. Domain structure of the epilayer changed depending on the type of substrate. Most residual strain in the epilayer was assigned as being due to the pseudomorphic stress for the epilayers having small lattice mismatch (<1%) against the substrate and to the thermal stress for large lattice mismatch (>1%) ones.