The electrical resistivity, heat capacity, superconducting upper critical magnetic field and magnetic susceptibility of NiBi 3 have been measured for the polycrystal and needle crystal. The temperature dependence of the resistivity ρ(T ) above the superconducting transition temperature can be explained by the parallel resistor formula. From ρ(T ), using the sum of two GruneisenBloch functions, we have obtained that the lower main value of the Debye temperature is 70 K and the higher one is 300 K. This is compatible with ω E ≡ 30.6 K and ω D ≡ 141 K obtained from the heat capacity using the hybrid Einstein-Debye model. We have compared the angular dependence of the critical magnetic field with that of the effective mass model and found an anisotropic mass ratio m b /m ⊥b ≈ 0.17 for the needle ( b-axis) crystal. Almost the same value of 0.14 is also obtained from the analysis of ρ(T ).

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The condition of the onset of superconductivity in highly homogeneous ultrathin Bi and Pb films has been investigated by measuring the temperature dependence of the sheet resistance R□. The experimental results suggest that highly homogeneous metal films with R□ lower than ∼6 k Ω could be superconducting, while those with R□ greater than ∼6 k Ω are insulating at zero temperature, in agreement with the condition of the onset of global superconductivity in granular films. The superconducting transition temperature Tc shows a remarkable decrease with increasing the normal-state sheet resistance, unlike the results of granular films.

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