ABSTRACT
The formation and the phase transitions of iron silicide by solid-phase epitaxy have been investigated by means of plan-view transmission electron microscopy, which enables us to observe a clean interface between Fe and Si. Layers of Fe were deposited on Si (100) at room temperature in an ultrahigh vacuum chamber. The sample was annealed in the electron microscope at a temperature between 673 and 1073 K. After annealing at 673 K, FeSi crystallites were formed with various orientations. When the annealing temperature was increased to 973 K, we found that the crystallites suddenly started to coalesce into grains of several hundreds of nanometers in size and polycrystalline beta-FeSi2 was formed. These phase transitions were also confirmed with electron energy-loss spectroscopy.
Subject(s)
Iron Compounds/chemistry , Phase Transition , Silicon Compounds/chemistry , Silicon/chemistry , Crystallography , Microscopy, ElectronABSTRACT
Alpha-silicon carbide was irradiated with Ne+ ions at room temperature to various fluences up to 7.5 x 10(20) Ne+ m(-2) and then isochronally annealed under observation with a transmission electron microscope. In all cases, thin regions were completely amorphized by irradiation and epitaxial growth occurred from the residual crystalline region by subsequent annealing. Crystal nucleation occurred with annealing at 1000 degrees C in the cases of 3.8 x 10(20) and 7.5 x 10(20) Ne+ m(-2) irradiation, and at 1100 degrees C in the cases of 1.3 x 10(20) and 2.3 x 10(20) Ne+ m(-2) irradiation. Growth or formation of bubbles was observed with annealing at 1000 degrees C after 1.3 x 10(20), 2.3 x 10(20), and 3.8 x 10(20) Ne+ m(-2) irradiation.