Electron beam-induced deposition using iron carbonyl and the effects of heat treatment on nanostructure

Electron beam induced deposition was performed in a scanning electron microscope with a field emission gun using a precursor of iron carbonyl. Nanometersized dots and freestanding rods were produced on a carbon film. The nanostructures of as-deposited and heat treated dots and rods were characterized using electron diffraction and electron energy loss spectroscopy in a transmission electron microscope. The as-deposited nano-dots and rods were amorphous containing Fe and C with a small amount of O near the surface. After heat treating at 600 degreesC for 1 h, the oxidized layer disappeared and several iron carbides were formed in the dots. In the freestanding rods, the amorphous deposit separated to alpha-Fe and Fe7C3 after the heat treatment.