Growth and characterization of doped ZnO films

摘要

We report here the synthesis of ZnO films by the pulsed-laser deposition technique using various novel conditions. The dopants are As, Ga, Al and N. The films show excellent crystalline quality with atomically smooth surface morphology. The electrical resistivity was found to be close to 2 × 10~(-4) ohm-cm and transmittance > 85% with both Ga and Al doping. Doping with As shows several distinct transitions in their electrical resistivity and strong aging effects. On the other hand, doping with Mn in ZnO reduces the grain size. On the other hand, doping with trivalent Er ions in ZnO films causes two effects: for high doping ( > 8 wt%), a substantial enhancement of diagonal piezo-optic effect (up to 3.7~*10~(-13) m~2/N at λ=633 nm) was observed due to creation of additional dipole moments at the interface of the film and the substrate, and higher electrical conductivity with enhanced 1.54 μm emission was demonstrated at room temperature for low concentration ( < 2 wt%) of Er. Furthermore, no quenching effects in emission characteristics at 1.54 μm were observed up to 2 wt % of Er-doping in ZnO at room-temperature.