Te doping study in molecular beam epitaxial growth of GaSb using Sb2Te3

Te evaporated from a Sb2Te3 compound source has been used to dope GaSb grown by molecular beam epitaxy. Te concentrations up to 2×1019 cm−3 followed a simple Arrhenius behavior with respect to source temperature. Efficient incorporation of Te remained insensitive to growth temperature until above 540 °C. Carrier density was found very close to Te doping level up to about 2×1018 cm−3. Above that, electron mobility as well as crystallinity deteriorated with increasing Te concentration. A dependence of surface reconstruction on Te doping level was observed. A complete change from (1×3) to (2×1) pattern occurred when Te concentration considerably exceeded its solubility limit in GaSb.