[en] Substitution and electrical activation of carbon in ¹²C⁺- and ¹²C⁺+³¹P⁺-implanted InP were studied for various annealing stages (773-923 K for 20 min). ¹²C⁺ was implanted into semi-insulating InP at a range of ∼3.0 μm with a total dose of 3x10¹⁴ cm^-2. The co-implantation of ¹²C⁺ and ³¹P⁺ was performed at a range of ∼2.0 μm with an individual dose of 3x10¹⁴ cm^-2. Rutherford back scattering, X-ray diffraction and Raman spectroscopy measurements showed the improvement of the crystallinity in the InP matrix by the annealing, indicating the disappearance of the introduced vacancy-interstitial pairs. Those were introduced during ion irradiation. All the annealed samples showed the n-type conduction by a van der Pauw method. The electric activation rate in the ¹²C⁺ implanted samples reached to 4.5% for those annealed at 923 K. For the co-implanted samples, the rate was slightly improved (∼7.3%). Nuclear reaction analyses for the ¹²C⁺-implanted samples using a ¹²C(d,p)¹³C reaction showed a tendency that carbon is easily incorporated into the interstitial lattice sites

[en] This paper reports on activities of boron in the binary Ni-B and the ternary Co-Fe-B melts determined by the electromotive force (emf) measurement. A boron crystal was mainly used as the reference electrode, and a ternary 29 wt pct B₂O₃-42 wt pct CaO-29 wt pct Al₂O₃ oxide melt was used as the electrolyte. Large negative deviations from Raoult's law have been found in both the binary and the ternary systems. The activity of nickel has been calculated from the measured boron activity by means of the Gibbs-Duhem equation. Standard Gibbs energies of formation of Ni₃B (s), Fe₂B (s), and Co₃B (s) were estimated and compared with available data