國立臺灣師範大學化學系S. MutoS. DaharaA. DattaC.-W. HsuC.-T. WuC.-H. ShenL. -C. ChenK.-H. ChenY.-L. WangT. TanabeT. MaruyamaH.-M. LinChia-Chun Chen2014-12-022014-12-022004-01-011347-5320http://rportal.lib.ntnu.edu.tw/handle/20.500.12235/42306Structure of nano-domes formed by Ga+ ion irradiation with a focused ion beam (FIB) apparatus onto GaN nanowires (NWs) was examined with conventional transmission electron microscopy (CTEM), electron energy-loss spectroscopy (EELS) and energy-filtering TEM (EF-TEM). The nano-dome consisted of metallic gallium, covered by a GaN layer, the structure of which is amorphous or liquid. It is considered that the dome structure is formed by preferential displacement of lighter element (N) and agglomeration of heavier one (Ga). 1 MeV electron irradiation onto the sample pre-irradiated by Ga+ ions at a dose below the threshold for the dome formation induced the N2 bubble formation without segregating Ga atoms, which suggests the radiation-enhanced diffusion (RED) of heavy atoms plays an important role in the nano-dome formation.GaNnanowiresion bombardmenttransmission electron microscopyelectron energy-loss spectroscopyenergy-filtering transmission electron microscopy