We develop an experimental evaluation method of interface strength for ductile submicron-dots on a hard substrate without collapse of the dot. The validity is examined by a copper (Cu) submicron-dot on a silicon dioxide (SiO 2 ) substrate with the rigid-layer of tungsten (W), which restrains the deformation and decreases the influence of complicated stress field due to the contact of tip. The diamond tip is dragged horizontally along the SiO 2 surface and the load is applied to the side edge of the W layer at a constant displacement rate using a modified atomic force microscopy. Both the lateral and the vertical load and displacement are continuously monitored during the test. The lateral load, F l , increases almost in proportion to the lateral displacement, δ l , and the Cu dot with the W layer is clearly separated from the SiO 2 along the interface. The restraint by the W layer works well so that there are little damages in both the delaminated W/Cu dot and the substrate. The delamination lateral load, F lC , is successfully measured.

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SynopsisThe effect of quaternized poly(4-vinyl pyridine)(QPVP) on the a$-elimination of serine catalyzed by pyridoxal (PL) or pyridoxal phosphate (PLP) and metal ions was investigated. In PLP-AP+ and PLP-Fe3+ systems, QPVP showed stimulation of about fivefold; this stimulation was reduced in the presence of 0.5 M KC1. The catalytic activities of PL-AP+ and PL-Fe3+ were lower compared to the corresponding PLP systems; stimulation by QPVP was also seen, though the extent of stimulation was smaller. The contribution of the electrostatic force between the polymer and the metal complex of the Schiff base was suggested to account for this stimulation. The pyridine moiety on the partially quaternized PVP did not seem to participate in the catalysis. In PLP-Cu2+, PL-Cu2+, and PLP-V02+ systems, however, QPVP showed marked inhibition. This inhibition by QPVP was also mitigated in the presence of 0.5 M KCl.

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