Ga-doped ZnO single crystal nanotips grown on fused silica by metalorganic chemical vapor deposition
20 October 2003
In situ Ga-doped ZnO nanotips were grown on amorphous fused silica substrates using metalorganic chemical vapor deposition. Structural, optical and electrical properties of as-grown ZnO nanotips are investigated. Despite the amorphous nature of fused-silica substrates, Ga-doped ZnO nanotips are found to be single crystalline and oriented along the c-axis.
Photoluminescence (PL) spectra of Ga-doped ZnO nanotips are dominated by near band-edge emission with negligible deep-level emission. The increase in PL intensity from Ga doping has been attributed to the increase of Ga donor related impurity emission. Current- voltage characteristics of the ZnO nanotips are measured by conductive-tip atomic force microscopy (C-AFM), which shows the conductivity enhancement due to Ga doping.