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Abstract: Sb/SnO2 bi-layer films were prepared using ion beam sputtering deposition (IBSD) and radio frequency (RF) magnetron sputtering deposition. The optimal parameters of SnO2 thin films were found to be dependent on the processing conditions of vacuum pressure and flow ratio of O2/(O2 +Ar). The as deposited bi-layer films were treated by ex situ pulsed ultraviolet laser beam at 355nm for the assistance of Sb-ion with SnO2 interface. This paper takes a closer look at the characteristics of the laser irradiation effect of Sb/SnO2 bi-layer films on the optical and electrical behavior and the interface microstructure of Sb/SnO2 by high resolution transmission electron microscopy (HR-TEM). After UV pulse laser irradiation of bi-layer films, crystalline Sb between amorphous Sb and SnO2 nanocrystalline thin films was observed. [Copyright &y& Elsevier]

Abstract: We investigated the influence of current stressing on a crystallographic microstructure of intermetallics in Cu/Sn/Cu solder joints using electron backscatter diffraction (EBSD). After direct current (DC) stressing at 150°C for 10 d, the total Sn of the Cu/Sn/Cu was converted into a tri-layer structure of Cu3Sn/Cu6Sn5/Cu3Sn. The Cu3Sn layers that grew on the cathode and anode are asymmetrical during DC stressing. A preferred direction <010> Cu3Sn along the current direction on the anode was found after current stressing. [Copyright &y& Elsevier]

Abstract: Multiferroic BiFeO3 films have been deposited on a number of substrates by RF magnetron sputtering. Two routes were adopted in order to obtain the films of high phase purity and accurate stoichiometry. The first was to sputter films at room temperature and then the BiFeO3 phase was formed after sintering at various temperatures under controlled ambient atmosphere. The second was to grow BiFeO3 in-situ at high temperature during sputtering. Although the sintered films grown on SrTiO3 substrates were epitaxial and showed better texture than the in-situ films, they had much poorer ferroelectric properties, due to the residual traces of intermediate phases formed during heating. Under right growth parameters, the in-situ films grown on the LaNiO3−x buffered SrTiO3 showed fully saturated ferroelectric hysteresis loops with large remanent polarisation of 64μC/cm2. Piezoresponse force microscopy (PFM) was used to examine the ferroelectric domain structures. When scanned without DC bias, fine spontaneous domains were observed. Under ±10V DC bias, PFM confirmed that the domains could be poled and switched. [Copyright &y& Elsevier]

Abstract: Sb/SnO2 bi-layer films were prepared on glass substrates using ion beam sputtering deposition (IBSD) and radio frequency (RF) magnetron sputtering deposition technology. The as-deposited bi-layer films were irradiated with a pulsed ultraviolet (UV) laser beam at 355nm for the characteristic modulation which is expected to receive interest in the subtle transition. The effect of laser irradiation on the optical and electrical behavior and the chemical state of the films was investigated using X-ray photoelectron spectroscopy (XPS). The conductivity of Sb/SnO2 after laser irradiation increased in comparison with that of SnO2 and as-deposited Sb/SnO2 thin films. The optical transmittance of laser irradiated Sb/SnO2 increased from 41% to 47%. [Copyright &y& Elsevier]

Abstract: Anisotropic microstructure is becoming a critical issue in microbumps used in 3-D integrated circuit packaging. We report here an experimental approach for controlling the microstructure of η-Cu6Sn5 intermetallic compound in microbumps by using 〈111〉 oriented and nanotwinned Cu pads as the under-bump-metallization. By electroplating arrays of large numbers of 〈111〉 oriented and nanotwinned Cu pads and by electroplating the Sn2.3Ag solder on the pads, we form η-Cu6Sn5 in the reflow at 260°C for 1min. The η-Cu6Sn5 showed a highly preferential growth along the 〈0001〉 direction. As reflow time is extended, the preferred texture of η-Cu6Sn5 changed to { }. The results indicate that we can control the uniform microstructure of η-Cu6Sn5 intermetallic by controlling the microstructure of the Cu under-bump-metallization. [Copyright &y& Elsevier]

Tin oxide (SnO 2-x ) thin films were prepared under various flow ratios of O₂/(O₂ + Ar) on unheated glass substrate using the ion beam sputtering (IBS) deposition technique. This work studied the effects of the flow ratio of O₂/(O₂ + Ar), chamber pressures and post-annealing treatment on the physical properties of SnO₂ thin films. It was found that annealing affects the crystal quality of the films as seen from both X-ray diffraction (XRD) and transmission electron microscopy (TEM) analysis. In addition, the surface RMS roughness was measured with atomic force microscopy (AFM). Auger electron spectroscopy (AES) analysis was used to obtain the changes of elemental distribution between tin and oxygen atomic concentration. The electrical property is discussed with attention to the structure factor.