Diffusion of dopants at high doping concentrations (~1020/cm3) of GaSb, GaInAsSb and InAsSb grown in a molecular beam epitaxy system and doped with Si, Be and Te were investigated. The electrically active doping concentration for each material was determined by van der Pauw measurements, while the doping profiles were measured by secondary-ion mass spectroscopy. The samples were annealed to analyze the diffusion behavior. Two different growth techniques to achieve high doping levels were compared: δ-doping, and deposition with reduced growth rate. The diffusion of Be in InAsSb:Be could not be prevented, neither by a low growth rate nor by intermediate GaSb spacers. A strong diffusion of Be and Te was found for δ-doped samples in InAsSb, whereas in slowly grown material the diffusion could be limited for Te as dopant.

Diffusion of Dopants in Highly (~1020/cm3) n- and p-Doped GaSb-Based Materials. O.Dier, M.Grau, C.Lauer, C.Lin, M.C.Amann: Journal of Vacuum Science & Technology B, 2005, 23[2], 349-53