Ef. Schubert et al., SI DELTA-DOPING OF (011)-ORIENTED GAAS AND ALXGA1-XAS GROWN BY MOLECULAR-BEAM EPITAXY, Applied physics letters, 64(17), 1994, pp. 2238-2240
Silicon delta-doping is studied on [011]-oriented GaAs and AlxGa1-xAs
grown by molecular-beam epitaxy. Hall measurements and secondary ion m
ass spectrometry on as-grown and on annealed samples reveal (i) that t
he electrical activity is reduced for the [011]-oriented samples as co
mpared [001]-oriented reference samples, (ii) that the electron mobili
ty is lower for [011]-oriented samples, and (iii) that the thermal red
istribution of Si impurities is comparable for both orientations. We f
ind a markedly different dependence of the electron mobility on the sp
acer thickness in selectively doped [011]-oriented AlxGa1-xAs/GaAs het
erostructures, which is explained by the reduced doping efficiency of
Si in [011]-oriented AlxGa1-xAs.