AVS 52nd International Symposium
    Electronic Materials and Processing Monday Sessions
       Session EM+NS-MoM

Paper EM+NS-MoM9
Large-scale Synthesis of GaN Nanowires by Direct Reaction of Gallium with Ammonia

Monday, October 31, 2005, 11:00 am, Room 310

Session: Novel Approaches in Wide Bandgap Semiconductors
Presenter: C.-H. Hsieh, National Tsing Hua University, Taiwan, R.O.C.
Authors: C.-H. Hsieh, National Tsing Hua University, Taiwan, R.O.C.
L.-J. Chou, National Tsing Hua University, Taiwan, R.O.C.
Correspondent: Click to Email
High-density GaN nanowires were synthesized on a large-scale Si substrate by direct reaction of metal gallium vapor under ammonia and hydrogen gases at 680~700°C. The morphology, composition and crystal structure were characterized by field-emission scanning electron microscope (FESEM, JSM-6500F), field-emission transmission electron microscope (FETEM, JEM-3000F) and X-ray spectrometer (SHINMADZU), respectively. From SEM images, the morphology of GaN nanowires is vermicular-like with average diameter of 200 nanometer and the length of up to 20 micrometer. The compositional line profile of TEM analysis revealed the vermicular-like GaN nanowires were uniformly doped with silicon and oxygen. The correspondent electron diffraction pattern indicated the vermicular-like GaN nanowires exhibiting poly-crystal structure. The XRD results of vermicular-like GaN nanowires show the hexagonal wurtzite structure. Furthermore, the cathodoluminescence (CL) characteristics demonstrate a broad band in the energy range of 2.1-3.1eV.