Transport properties of Be- and Si-doped AlSb

Thick epitaxial layers of AlSb(Si) and AlSb(Be) were grown by molecular bea m epitaxy and characterized by variable-temperature Hall/van der Pauw measu rements. Si is shown to be predominantly an acceptor in AlSb, with an energ y level 33 +/- 4 meV above the top of the valence band. Be is also an accep tor, with an energy level 38 +/- 4 meV above the top of the valence band. B e is a robust doping source for p-AlSb for carrier densities ranging from 1 0(15) to 10(19) cm(-3). Background impurity levels in AlSb can be assessed by measuring the transport properties of lightly doped AlSb(Be) layers. (C) 2000 American Institute of Physics. [S0021- 8979(00)00811-2].