The effect of a native silicon dioxide layer on metal-induced crystallization of hydrogenated amorphous silicon ͑a-Si:H͒ was investigated. Several samples, deposited by the plasma-enhanced chemical vapor deposition technique, were exposed to different ambients for different times to allow for the growth of SiO 2 layers of different thicknesses. Then, aluminum was used to crystallize the samples using metal-induced crystallization at temperatures far below the solid-phase crystallization temperature of a-Si. In this study, we focused on the effects of the native oxide layer on crystallization and crystallization rates of the samples, as determined by X-ray diffraction. Following crystallization, scanning electron microscopy, environmental scanning electron microscopy, energy dispersive spectroscopy, and atomic force microscopy were used to examine and compare the morphology and chemical composition of the surface of the different samples. Finally, an explanation of the findings is presented.

In this work the effect of nickel (Ni) plating process on the hydrogen (H) and moisture content of hermetic packages such as those used in optoelectronics was investigated. The work offers an explanation of moisture formation inside hermetic packages by showing that the problem arises from the electroless plating of Ni, which is found to be inherently rich in H. The effects of the Ni plating process, baking, and Au thickness on the moisture and hydrogen content of hermetic packages were thoroughly explored. It was observed that baking the package components before sealing alleviates the problem of moisture formation inside the package but does not fully eliminate it. It was only after changing the Ni plating process from electroless to electrolytic that the moisture problem actually disappeared. This investigation showed that moisture formation inside hermetic packages is due to H evolution from the electroless Ni which eventually reacts with surface oxides to form H2O. SIMS analysis of electroless and electrolytic Ni showed that electroless Ni is around 10-fold richer in H compared with its electrolytic counterpart. SIMS analysis also showed that H content in electroless Ni can be significantly reduced with heat treatment.

No abstract

In this work we investigated the effect of Nickel (Ni) plating process on the Hydrogen (H) and moisture content of hermetic packages such as those used in optoelectronics. The work offers an explanation of moisture formation inside hermetic packages by showing that the problem arises from the electroless plating of Ni which is found to be inherently rich in H. The effects of the Ni plating process, baking, and Au thickness on the moisture and hydrogen content of hermetic packages were thoroughly explored. It was observed that baking the package components before sealing alleviates the problem of moisture formation inside the package but it doesn't fully eliminate it. It was only after changing the Ni plating process from electroless to electrolytic that the moisture problem actually disappeared. Our investigation showed that moisture formation inside hermetic packages is due to H evolution from the electroless Ni which eventually reacts with surface oxides to form H2O. SIMS analysis of electroless and electrolytic Ni showed that electroless Ni is around ten folds richer in H compared to its electrolytic counterpart. SIMS analysis also showed that H content in electroless Ni can be significantly reduced with heat treatment.

No abstract