P-Type and n-type doping in GaSb and Ga 0.8In 0.2Sb layers grown by metalorganic vapor phase epitaxy

Abstract

P-type and n-type GaSb and Ga 0.8In 0.2Sb layers have been grown on GaSb and GaAs substrates by metalorganic vapor phase epitaxy (MOVPE) using silane and diethyltellurium (DETe) as the dopant precursors, respectively. Hall measurements show that the concentration and mobility of holes and electrons in GaSb and Ga 0.8In 0.2Sb are higher when the layers are grown on GaSb substrates than when grown on GaAs substrates. Secondary ion mass spectrometry (SIMS) results show that the incorporation of Si and Te is higher when GaSb substrates are used. The electron concentration increased from 5×10 16 to 1.5×10 18 cm −3 as the Te concentration was increased from 1×10 17 to 5×10 18 cm −3 . As the Te concentration was increased further, the electron concentration decreased, with only about 1% of the Te electrically active at a Te concentration of 2×10 20 cm −3 .