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Abstract: The roughness evolutions of micro-crystalline silicon thin films (μc-Si:H) with different growth rates prepared by chemical vapor depositions have been investigated by atomic force microscopy. The growth exponent β was measured as 0.8±0.03, 1.1±0.07 and 0.75±0.02 for three sets of samples prepared by PECVD with and without hydrogen dilution ratio modulation and by HWCVD, respectively, and does not correlated with the deposition rate in a set. However, the root-mean-square roughness and lateral correlation length decrease with increasing the deposition rate for both PECVD and HWCVD process. We suggested that the nonstationary growth with large β is correlated with the shadowing effect. The influence of the deposition rate on the surface roughness could be related to the diminishing of the shadowing effect by surface species diffusion with higher mobility on an H-covered surface. The initial surface and nucleation condition play an important role in the surface roughness evolution. [Copyright &y& Elsevier]

• The hardness and modulus changes of sequential He-ion irradiation exhibited damage promotion for the electron pre-irradiated NBS1 and NBS2, while recovery effect for the NBS3. • For three NBS glasses with different electron pre-irradiation doses, there are composition-dependent sensitive discrepancy in the subsequent He-ion irradiation induced hardness and modulus changes. • Electron irradiation induced pre-existing responses may cause a more drastic synergistic effect in sequential irradiation on borosilicate glass and alter the final equilibrium level in modulus change. Mechanical property and microstructure changes induced by 500-keV He2+ have been investigated in three kinds of 1.2-MeV electron pre-irradiated Na 2 O-B 2 O 3 -SiO 2 (labeled as NBS) glasses. The glasses before and after irradiation are analyzed by nanoindentation methods and infrared spectroscopy. The hardness and modulus variation of sequential He-ion irradiation in the electron pre-irradiated NBS1 and NBS2 specimens exhibited damage promotion. On the contrary, a pronounced recovery effect is observed in the behavior of NBS3 glass. Both the hardness and modulus changes are correlated with the microstructure evolution, and the corresponding micro-mechanism is discussed. Moreover, the pre-existing responses induced by electron irradiation differ from the ion irradiation caused, which can alter the damage equilibrium level of modulus on borosilicate glass under He-ion sequential irradiation. This study of electron-ion sequential irradiation effects will provide new insights for understanding the irradiation response of nuclear waste glass matrix under mixed radiation fields. [ABSTRACT FROM AUTHOR]

• The element depth profiles and microstructures of three types of ternary sodium borosilicate glasses induced by 1.2 MeV electron irradiation were studied. • The depletion of elements at the irradiated surface layer was affected by the composition of the pristine glass. • The depleted depths of all the elements were the same in the same irradiated NBS glass, and increased with a decrease in the R value of the NBS glasses and an increase in the electron dose. The study of the electron irradiation effect on borosilicate glass is highly significant for the evaluation of its radiation resistance in a strong ionizing radiation environment. In this study, the element depth profiles of three types of ternary sodium borosilicate glasses (named NBS1, NBS2, and NBS3) induced by 1.2 MeV electron were characterized using time-of-flight secondary ion mass spectrometry (ToF-SIMS). The molar ratio R = [Na 2 O]/[B 2 O 3 ] of NBS1, NBS2, and NBS3 were 1.34, 0.75, and 0.40, respectively, while the molar ratio K = [SiO 2 ]/[B 2 O 3 ] was fixed at 4.04. The results indicate that the amount by which the elements Na, B, and O decreased in the irradiated surface layer were different in all the samples. In particular, the depletion depths of all the elements were the same in the same irradiated NBS glass and increased with a decrease in the R value. The difference in the surface depletion of the three NBS glasses is related to the glass composition. In addition, the structure of the irradiated surface layer was characterized by X-ray photoelectron spectroscopy (XPS), the results of which suggested an increase in network polymerization and transformation of 4- to 3-coordinated boron. Combined with the structure of the irradiated surface layer, the formation mechanism of the irradiated surface layer was further discussed. These results are extremely important for understanding the changes in surface behavior caused by strong ionizing radiation. [ABSTRACT FROM AUTHOR]

• Mechanical property changes of three-composition pristine and Au3+ ions pre-irradiated NBS glasses induced by 0.5MeV He2+ ions irradiation were studied. • No obvious composition dependence was observed in the hardness changes of He-ion irradiated NBS glasses. • Partial recoveries in the mechanical property variation and the saturation damage level of Au-ion pre-irradiated glasses were induced by He-ion sequential irradiation. • The saturation damage level was affected by the composition of the pristine glass. This study explored the mechanical property changes in three kinds of pristine and Au3+ pre-irradiated Na 2 O-B 2 O 3 -SiO 2 (labeled as NBS) glasses induced by 0.5-MeV He2+ ions over a broad fluence range. The glass samples were prepared with different R values = [Na 2 O]/[B 2 O 3 ] (0.40, 0.75 and 1.34). After He-ion irradiation, the hardness diminished and finally reached saturation, the modulus showed a slight decrease for the NBS1 and NBS2 glasses, but the NBS3 glass exhibited no significant change. The mono He2+ ion irradiation scenario did not show the self-recovery effect of Au3+ ion irradiation scenario. The sequential He-ion irradiation can lead to damage recovery in the Au-ion pre-irradiated glasses. The final equilibrium state was affected by the composition of pristine glass, which can be attributed to lower thermal stability and the phase separation characteristic of NBS3 glass. Such results hold great significance for understanding the radiation damage caused by multiparticle irradiation in the glass matrix of nuclear wastes. [ABSTRACT FROM AUTHOR]

Abstract: Indium tin oxide (ITO) films were grown without external heating in an ambient of pure argon by RF-magnetron sputtering method. The influence of argon ambient pressure on the electro-optical properties of as-deposited ITO films was investigated. The morphology, structural and optical properties of ITO films were examined and characterized by X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), atomic force microscopy (AFM) and UV–VIS transmission spectroscopy. The deposited ITO films with a thickness of 300nm show a high transparency between 80% and 90% in the visible spectrum and 14–120Ω/□ sheet resistance under different conditions. The ITO films deposited in the optimum argon ambient pressure were used as transparent electrical contacts for thin film Cu(In,Ga)Se2 (CIGS) solar cells. CIGS solar cells with efficiencies of the order of 7.0% were produced without antireflective films. The results have demonstrated that the developed ITO deposition technology has potential applications in thin film solar cells. [Copyright &y& Elsevier]