A method of studying short-lived radio-nuclides produced by the internal beam in a synchrocyclotron is described. Preliminary results on a number of proton-produced activities in the mass range below 70 are given.

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Some rare-earth elements, Tb, Er, Yb (including Y) and some of their respective silicides were found to make ohmic contacts to n-type silicon. Forward I/V and photoresponse measurements give values of about 0.7 eV for the Schottky-barrier height to p-type silicon. The sum of this value and of the experimentally estimated barrier height to n-type silicon, 0.4 eV, corresponds to the band gap of silicon.

The formation of iridium silicides from the interaction of iridium films with single-crystal silicon substrates has been studied from 350 to 1000 °C. Three distinct phases, IrSi, IrSi1.75(?), and IrSi3, were identified. Different modes of formation were observed and investigated. IrSi and IrSi1.75 form in layers parallel to the substrate at temperatures from 350 to 900 °C. The growth of IrSi3 from nuclei that spread laterally occurs at about 1000 °C, where possible the kinetics were systematically studies.

Metal–silicon and silicide–silicon diodes were fabricated by depositing thin layers of the metals Hf, Zr, Mn, Ni, and Rh on 〈111〉 epilayers of silicon, and annealing to transform the metal–silicon junctions to silicide–silicon junctions. A formation of the silicides was followed, and the stoichiometries were determined by ion back‐scatter analysis. The compositions and approximate formation temperatures were (HfSi, 700 °C; HfSi2, 850 °C), (ZrSi2, 700 °C), (MnSi, ≈ 500 °C; MnSi1.7, 800 °C), (NiSi, ≈ 600 °C; NiSi2, 850 °C), (RhSi, 600 °C). These temperatures are below those of the liquid phase eutectica hence indicating that the silicide forms in solid–solid reactions. The barrier heights were measured by the photoelectric method, giving the values: (Hf, 0.81 eV; HfSi 0.73 eV), (Mn, 0.77 eV; MnSi, 0.76 eV; MnSi1.7, 0.72 eV), (Ni, 0.75 eV; NiSi2, 0.70 eV), (Rh, 0.80 eV; RhSi, 0.70 eV).

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