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Articles you may be interested inElectronic transport properties on transition-metal terminated zigzag graphene nanoribbons Electrical resistivity in the temperature range of 2-1100 K and Hall-effect measurements from 10 to 300 K of CoSi 2 , MoSi 2 , TaSi 2 , TiSi 2 , and WSi 2 polycrystalline thin films were studied. Structure, composition, and impurities in these films were investigated by a combination of techniques of Rutherford backscattering spectroscopy, x-ray diffraction, transmission electron microscopy, and Auger electron spectroscopy. These silicides are metallic, yet there is a remarkable difference in their residual resistivity values and in their temperature dependence of the intrinsic resistivities. For CoSi 2 , MoSi 2 , and TiSi 2 , the phonon contribution to the resistivity was found to be linear in temperature above 300 K. At high temperatures, while a negative deviation from the linearity followed by a quasisaturation was observed for TaSi 2 , the resistivity data ofWSi 2 showed a positive deviation from linearity. It is unique that the residual resistivity, p(2 K), of the WSi 2 films is quite high, yet the temperature dependent part, i.e., p(293 K) -p(2 K), is the smallest among the five silicides investigated. This suggests that the room-temperature resistivity of WSi 2 can be greatly reduced by improving the quality of the film, and we have achieved this by using rapid thermal annealing.

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Electrical properties of high-dose (1.6X 10' at./cm') H+-implanted B-doped silicon have been investigated using transient capacitance spectroscopy, capacitance-voltage, and spreading resistance profiling.The role of hydrogen is twofold: to interact with the defects created by ion implantation, modifying their electrical properties, and to neutralize the shallow-acceptor dopants. The evolution of the defects responsible for the deep levels and the depth of the neutralized region have been investigated after isochronal annealing at various temperatures up to 800'C. Deep-level transient spectroscopy spectra show three hole traps; two of them, H(0.67), H(0.33), have been tentatively identified as vacancy-hydrogen complexes (VH2, VH3) while the attribution of the third, H(0.23), detected in the samples annealed at 400-450'C, is uncertain. As a function of the heat treatment, the total number of defects is strongly reduced at 300'C, it increases for T )300 'C and at the highest temperatures, namely 800'C, the defects disappear. The first decrease is attributed to the formation of neutral VH4 complexes and the disappearance to complete decoration of point defects or their agglomeration. The thickness of the passivated region has a minimum at 300'C, which corresponds to the formation of the stable VH4. At lower temperatures, the hydrogen necessary for the passivation is the unbonded one and presumably comes from the implantation process itself. At higher temperature, H comes from the breaking of the VH4 or H"complexes. These results are in good agreement with our previous studies concerning the role played by hydrogen in affecting the crystal properties of silicon.