ABSTRACT
The main purpose of this paper is to investigate the optical properties of p-type ZnO film based on P doping. ZnO film was grown by Atomic layer deposition (ALD) on InP subsrate in this experiment, and phosphorus diffused into ZnO lattice by annealing treatment at different temperature (500, 700 °C). The optical properties of samples were investigated by photoluminescence (PL) spectroscopy, which indicated that the annealing temperature is the important factor influencing the phosphorus diffusion doping. The low-temperature PL spectra of the sample which annealed at 700 °C for 1 h exhibited acceptor related emission peaks located at 3.351, 3.311, 3.246 and 3.177 eV, which were attributed to A °X, FA, DAP and DA-1LO, respectively. The acceptor binding energy is estimated to be about 122 meV, which is agreed with the theoretic values in phosphorus-doped ZnO films. In this paper, through thermal diffusion method to realize the p-type doped ZnO thin films, it solved the main problems which limited the development of ZnO based optoelectronic devices, and has an important significance for the development of the ZnO semiconductor materials and ZnO based photoelectric device.
ABSTRACT
In the present paper, MgxZn1-xO and MgxZn1-xO/Au/MgxZn1-xO multilayer structures of transparent conductive film were prepared by the simple operation of sol-gel and RF magnetron sputtering method on quartz substrate respectively and then they were annealed. The surface, electrical, crystal and optical properties of the films at different annealing temperature were determined by UV-Vis spectrophotometer, X-ray diffraction, photoluminescence and Hall effect, respectively. The influence of annealing temperature on the films was also investigated. The testing results indicated that the films with good c-axis orientation presented hexagonal wurtzite structure. With increasing Mg components, the optical band gap of ZnO thin film increased gradually. There was an obvious blue shift phenomenon in PL spectrum and absorption spectrum line. But the electrical properties of the films declined. In MgxZn1-xO/Au/MgxZn1-xO multilayer structure of thin film samples, the existence of Au interlining led to the poor optical properties of thin film, and the light transmittance in the ultraviolet region was 60%. Compared with MgxZn1-xO film, the electrical properties of MgxZn1-xO/Au/MgxZn1-xO multilayer structure of transparent conductive film were improved, the resistivity and migration rate were significantly increased. In addition, high temperature annealing treatment could effectively improve the crystal quality of thin film and further improve the electrical characteristics of the samples. After the annealing treatment at 500 °C, migration rate of the film reached to 40.9 cm2 · 1 Vs(-1) while the resistivity was 0.0057 Ω · cm. Due to the rising of temperature, the crystal size increased from 25.1 to 32.4 nm to reduce the mobility of the film. Therefore, MgxZn1-xO/Au/MgxZn1-xO multilayer structure of transparent conductive film played an important role in promoting the ZnO transparent conductive film application in deep ultraviolet devices.
ABSTRACT
In the present paper, Mg(x)Zn(1-x)O nanofibers with different doping concentration were prepared by atom layer deposition (ALD) using polyvinyl pyrrolidone (PVP) nanofibers as template, which were synthesized by electrospinning. The influence of different Mg doping concentration on the structure and optical properties of composite nanofibers was investigated. The samples were characterized by field emission scanning electron microscopy (FESEM), ultraviolet visible (UV-Vis) absorption spectroscopy and photoluminescence (PL) spectra. The doping of Mg did not change the morphologies of ZnO nanofibers, the morphologies of all the samples were very similar while the diameter of Mg(x)Zn(1-x)O-PVP composite nanofibers became larger after doping. With the increase in the Mg doping concentration, the absorption edge shifted to larger energy side, revealing the band gap tenability of Mg(x)Zn(1-x)O nanofibers. Meanwhile, a significant blue shift of the UV emission peak from 377 to 362 nm was observed in PL spectra. Compared with ZnO-PVP composite nanofibers, the UV emission intensity of Mg(x)Zn(1-x)O-PVP composite nanofibers was much stronger. Component control Mg(x)Zn(1-x)O nanofibers can be synthesized by this method. The doping of Mg elements in ZnO can effectively improve the band gap of ZnO-PVP nanofibers and the intensity of UV emission.
