Measurement of the impurity diffusion of In in Ni single crystals by secondary-ion mass spectrometry (SIMS)

Secondary-ion mass spectrometry (SIMS) has been used to study the impurity diffusion ion of indium in nickel single crystals over the temperature range of 777 to 1513 K. The diffusion coefficients ranged from 4.1 × 10 −17 to 2.4 × 10 −9 cm 2 s −1 . Comparison of these values with radiotracer data in the literature shows very good agreement. The resulting values for the frequency factor and activation energy of the lattice impurity diffusion are: D o = 1.1 ± 0.4 cm 2 s −1 and Q = 250 ±4 kJ mol −1 . "Short-circuit" contributions to the diffusional flux were evident in three specimens annealed at the lowest temperatures. Evaporation of the solute during annealing was observed in some cases and is discussed in terms of Reimers's analysis. The applicability of SIMS to impurity diffusion studies is demonstrated.