Structural properties of Bi-stabilized reconstructions of GaInAs(100) surface

Bismuth (Bi) is a surfactant which controls the electronic and structural properties of epitaxially grown GaInAs and GaInP alloys. The authors have studied Bi-terminated surfaces of GaInAs(100) layers, deposited onto InP(100) substrates, by means of scanning tunneling microscopy and spectroscopy and x-ray photoelectron spectroscopy. It appears that Bi stabilizes an interesting ( 2 × 1 ) surface reconstruction on GaInAs(100). Under certain conditions, this reconstruction undergoes a phase transition to ( 2 × 4 ) , which has about one-half of the Bi content of the ( 2 × 1 ) surface. Based on the experimental findings, they discuss mechanisms leading to this phase transition.