Ca0.5Sr0.5F2/GaAs (100) for epitaxial regrowth and electron-beam patterning

Abstract Layers of GaAs and Ca 0.5 Sr 0.5 F 2 are grown by molecular beam epitaxy. The morphology, orientation, composition and crystallinity of the layers are analyzed as a function of growth temperature and surface treatment. The fluoride layers show a high degree of crystallinity and a smooth surface morphology. The crystallinity and morphology of the GaAs overlayer are improved by electron irradiation of the fluoride surface prior to GaAs growth followed by a two-step growth procedure for the GaAs overlayer. A technique of electron-beam patterning of the fluoride layer is developed and the formation of 3–5 μm features is demonstrated.