Optoelectronic properties of Indium-assisted Gallium Nitride Nanowires

In this work, the optoelectronic properties of H2 diluted Gallium Nitride Nanowires (GaN-NWs) grown on Si substrate were examined. The GaN-NWs were deposited on Indium (In) coated p-type Si substrate by thermal chemical vapor deposition process using GaN powder and pure N2, H2 as precursor gases. A variety of techniques such as Scanning Electron Microscopy (SEM), Fourier Transform Infrared (FTIR) Spectroscopy, Raman Spectroscopy and Photoluminescence (PL) Spectroscopy were used to characterize the grown materials. PL spectra reveals a broad emission band ranging from 2.5 eV to 3.2 eV with intense peak centered at 2.92 eV which is red shifted with respect to bulk GaN (3.4 eV). This might be due to the formation of different electronic energy bands in the presence of H2 and In catalyst which breaks the periodicity of the lattice and modifies the band structure locally.