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The influence of a sputter-deposited titanium adhesion layer on glass and Si (1 1 1) substrates with or without exposure of titanium layer surface to the atmosphere on the growth mode of the tantalum films was studied. It was found that, because of the well match of the cell constants between the deposited Ta and the underlying Ti, the tantalum films continuously deposited on the adhesion layer of titanium grown without breaking vacuum always grew with the orientation following that of the bottom titanium layer and nucleated bcc α phase of tantalum with low degrees of orientation. After exposure of the bottom titanium layer surface to atmosphere, the absorption and diffusion of oxygen and other impurity atoms on the surface would promote a higher lever of oxidation and favor to form more and more titanium suboxides at the Ti surface. The increase of titanium suboxides at the Ti surface change the lattice mismatch between the underlying titanium film and the bcc-Ta film, which disturbed the nucleation of α-Ta and promoted the growth of β-Ta. Consequently, the electrical properties of the Ta/Ti bi-layer films were significantly changed.

In order to provide the equivalent of a human anti-human protein antibody as positive control in ELISAs, a goat-human antibody complex was created using chemical cross-linking. The resulting hybrid complex had a larger molecular size on HPLC and SDS-PAGE. In ELISA, the goat-human complex bound to human antigen and was detectable by a secondary anti-human conjugate. The method to make the hybrid complex is simple, cost-effective and can be used to make human-like antibodies to many human proteins.

The topography and size of damage on the surface of HOPG (Highly Oriented Pyrolitic Graphite) bombarded by high fluence (1x10(16) ions/cm(2)) of H+ ions were observed and studied. In this work, 457 STM images of each one with 9x9 nm(2) area were obtained. From 163 of these pictures visible damage was found. In these 163 STM images the diameter of most damage is from 0.2 to 0.8 nm. In this study the number density of visible damage is much less than the ion fluence. The probability of damage is only about 1.8x10(-4). The possible mechanism of damage formation is also analyzed and discussed.

DX center-like traps were detected and characterized by DLTS in the n + -Ga 0.7 Al 0.3 As buffer layers of PIN heterostructures. Their thermal capture barriers were measured by an original method that used the intrinsic superlattice layer as a light source to photoionize the captured electrons. The traps are very close to the conduction band edge, and have a large capture barrier. They are located at 0.04 eV and 0.01 eV under the conduction band.

We have studied the behaviour of electron irradiation induced defects in δ-doping GaAs superlattices, using capacitance-voltage and deep level transient spectroscopy. For the planar doping used (10 11 SSi cm −2 ) with a distance of 70 a between each plane, we observed a delocalization of the carriers, in agreement with theoretical calculation. The defects created by the irradiation are identical to the defects created in bulk GaAs. However, we observed in addition two new defects which are tentatively ascribed to a complex formed between the silicon dopant and the arsenic vacancy.