Effect of antimony ambience on the interfacial misfit dislocations array in a GaSb epilayer grown on a GaAs substrate by MOCVD

Abstract

The crystal quality and structural properties of GaSb thin films grown on a semi-insulator GaAs (001) substrate by metalorganic chemical vapor deposition (MOCVD) using triethylgallium and trimethylantimony were characterized by high-resolution X-ray diffraction and high-resolution transmission electron microscopy. The nucleation of the interfacial misfit dislocations (IMF) array in the GaSb/GaAs interface, which is dependent on the antimony ambience, was investigated by varying the V/III ratio. Our experiment results showed that the IMF array and threading dislocation density are modified in the GaSb epilayer with different antimony ambiences. The GaSb thin film grown by the IMF mode on GaAs was confirmed under our optimal growth condition, and the hole density and mobility of GaSb thin films were found to be 5.27 × 1016 cm <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">-3</sup> (1.20 × 1016) and 553 cm <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> /V-s (2340) at RT (77 K) from Hall measurements. We suggest that the IMF growth mode can also be applied to fabricate the GaSb film on GaAs by MOCVD for application in microelectronic devices.