Solidification features of cast and vertically fed Te-doped GaSb materials

Dilute Te-doped GaSb alloys have been prepared by the vertical feeding method (VFM) using both casting and feeding configurations. The structural and optical properties of the samples were characterized by etching, X-ray diffraction and cathodoluminescence in the scanning electron microscope. The obtained results confirm the variation of the segregation coefficient k observed in previous VFM Te-doped GaSb experiments. The increase of k and the grain structure refinement are attributed to the increase of the interface velocity. The feeding configuration of the VFM seems to be the most appropriate one to control segregation and grain size for Te-doped GaSb alloys.