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ZnO thin films doped with aluminum (AZO) were deposited on silicon dioxide covered p-Si (100) substrates by radio frequency magnetron sputtering, to fabricate AZO/SiO2/p-Si heterojunction, as an absorber for ultraviolet cell. The optical and electrical properties of the Al doped - ZnO films were characterized by UV-VIS spectrophotometer, current-voltage measurement, and four point probe technique, respectively. The results show that AZO films have good quality. The electrical junction properties were investigated by I-V measurement, which reveals that the heterojunction shows typical rectifying behavior.

Microstructural, optical and electrical properties of Sc-doped ZnO films grown by RF magnetron sputtering at room temperature were investigated. The deposition pressure was varied from 0.3 to 2.0 Pa. XRD spectra indicated that the (100) peak of the film weakened as the reaction pressure decreased and the (110) peak strengthened at a preferred pressure, 0.3Pa. Compare with (100) and (110) peaks, the intensity of (002) peak was relative weak. The strain in the film was investigated. The average transmittance of these films was above 90% in the wavelength range from 400 to 800 nm, while decreased in short wavelength region due to the light scattering. More significantly, various optical band gap of the films were found correspond with different pressure. The causation might be due to the Burstein-Moss effect.

By using low cost, low-temperature hydrothermal approach and spin-coating technique, well-aligned ZnO nanorods have been successfully prepared on ITO substrates. The ITO substrate was pre-patterned with ZnO particles as a seed layer for the subsequent nucleic hybridization. The intuitionistic crystallinity of oriented ZnO nanorod array was characterized by scanning electron microscopy (SEM) and X-ray diffraction (XRD), respectively. It is shown that the preferred orientation growth of the wurtzite structure along (002) plane is easily obtained with the approach. The size of the ZnO nanorods has been found to be dramatically dependent on the concentration of zinc content in the solution.

An optimal energy interval in ion-assisted deposition of high crystalline films is predicted in the modeling of ion impacting on surface. The result is in good agreement with the presented experiments. The possible application of the evaluation of ion role for the fabrication of potential thin film materials is expected.

First-principles calculations have been performed to study the adsorption of Aluminium(Al) on the Si(001)2×1 surface. The optimized geometries and electronic structures of the adsorption system were investigated. The adsorption energy at various adsorption coverages(Θ) from half a monolayer(ML) to one monolayer has been calculated. The most stable adsorption sites were consequently determined to be HH site and T3-T4 site, respectively. There is obvious evidence that the asymmetric aspect of the Si-Si dimer becomes the symmetric one which has been observed at the coverage of 0.5ML or 1ML. In addition, the bond length of Si-Si was found to be considerably elonged upon the Al adsorption. The work function calculations have shown that the aspect of work-function change for the Si(001) surface due to the adsorption of Al is different from that of the alkali metals adsorption reported in some previous works. The surface formation energy was also calculated. The absolute value of the surface formation energy was found to decrease with increasing coverage indicating that 1ML is not a saturation coverage. In order to shed light on the nature of the Al-Si bond and the character of silicon surface, the density of states and band structure of the system were calculated.

The BSF of mono-crystal silicon cell is studied in this paper. It simply states the principle and formation process of BSF, and studies the evenness of BSF. In the experiment, we analyze BSF formed by taking different sintering temperature, heating rate and setting different time, develop by chemical reagent and observe at high magnification scope, analyze and get the optimal parameters of forming even BSF and further improve conversion efficiency of silicon chips.