Structural Characteirzation of GaAs_(1-x)Bi_x Alloy by Rutherford Backscattering Spectrometry combined with the Channeling Technique

摘要

Rutherford backscattering spectrometry (RBS) combined with the channeling technique has been applied to a GaAs_(1-x)Bi_x epilayer to investigate concentration and lattice location of Bi atoms and crystalline quality of the epilayer. The metastable GaAs_(1-x)Bi_x alloy layer was grown on a GaAs substrate at a temperature as low as 365 deg C. The GaBi mole fraction obtained was 2.6 +- 0.2%. Angular scans for [100] and [111] crystal directions reveal that the incorporated Bi atoms exactly occupy substitutional sites in the GaAs crystal lattice. Crystal perfection of the GaAs_(1-x)Bi_x metastable alloy is fairly good in spite of the low growth temperature.