Fabrication and Characterization of Gallium Nitride Nano-Wire Light-Emitting Tunneling Diodes

• Main Authors: Bo-Chun Yeh, 葉伯淳
• Other Authors: 彭隆瀚
• Format: Others
• Language: zh-TW
• Published: 2008
• Online Access: http://ndltd.ncl.edu.tw/handle/22339783143816762377

碩士 === 國立臺灣大學 === 光電工程學研究所 === 96 === In this thesis, we present the growth, analyzing, fabrication, and characterization of gallium nitride (GaN) nanowires light emitting devices. The growth of GaN nanowires structures was conducted in a home-built vapor-liquid-solid (V-L-S) system. The following spectroscopic instrument of scanning electron microscopy (SEM), photoluminescence (PL), energy dispersive spectrometer (EDS), transmission electron microscopy (TEM), and X-ray photoelectron spectroscope (XPS) were used to characterize the morphology, composition, and crystalline properties of the GaN nano-structures grown by the V-L-S method. From the PL analysis pumped by a 266nm Nd:YAG solid-state laser, we observed a peak emission wavelength at 363nm with a full width at half maximum (FWHM) of 42nm, and a wideband yellow emission. From the EDS and XPS data analysis we identify the material’s composition to be binary GaN. Data from the TEM analysis suggest the GaN nanowires grown by the V-L-S method to be single crystalline. Light-emitting devices base upon the V-L-S-grown GaN nanowires were further fabricated and characterized. From the current-voltage, electroluminescence (EL), and photocurrent measurements, these devices exhibit non-ideal electrical characteristic. The devices emit ultraviolet and visible light under both bias polarities, and are observed a large spectral blue shift as the injection current increased. Finally, we give a photo-assisted tunneling model to explain the EL mechanism of this device.