title: Laser-induced oxidation kinetics of bismuth surface microdroplets on GaAsBi studied in situ by Raman microprobe analysis.
abstract: We report the cw-laser-induced oxidation of molecular-beam-epitaxy grown GaAsBi bismuth surface microdroplets investigated in situ by micro-Raman spectroscopy under ambient conditions as a function of irradiation power and time. Our results reveal the surface droplets are high-purity crystalline bismuth and the resultant Bi2O3transformation to be β-phase and stable at room temperature. A detailed Raman study of Bi microdroplet oxidation kinetics yields insights into the laser-induced oxidation process and offers useful real-time diagnostics. The temporal evolution of new β-Bi2O3Raman modes is shown to be well described by Johnson-Mehl-Avrami-Kolmogorov kinetic transformation theory and while this study limits itself to the laser-induced oxidation of GaAsBi bismuth surface droplets, the results will find application within the wider context of bismuth laser-induced oxidation and direct Raman laser processing.
authors.forename: J A
authors.initials: JA
authors.lastname: Steele
authors.forename: R A
authors.initials: RA
authors.lastname: Lewis
mesh_terms: D001152:Arsenicals / Q000737:chemistry* / Q000528:radiation effects; D001729:Bismuth / Q000737:chemistry* / Q000528:radiation effects; D003460:Crystallization / Q000379:methods*; D005708:Gallium / Q000737:chemistry* / Q000528:radiation effects; D007834:Lasers; D008422:Materials Testing; D010084:Oxidation-Reduction / Q000528:radiation effects; D011829:Radiation Dosage; D012996:Solutions; D013059:Spectrum Analysis, Raman / Q000379:methods*; D013499:Surface Properties / Q000528:radiation effects
chemical_list: D001152:Arsenicals; D012996:Solutions; C043055:gallium arsenide; D005708:Gallium; D001729:Bismuth