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Female guppies were fed diets containing different levels and ratios of calcium (0.03%, 0.59% and 1.28%) and phosphorus (0.05%, 0.53% and 1.23%) for 12 weeks. Growth and feed conversion rates were found to be positively correlated with dietary levels of P but not of Ca. Lower levels of vertebral ash, Ca and P were also seen in fish given 0.05% P diets. The dietary phosphorus level required for optimum growth and mineralisation was found to fall between 0.53% and 1.23%.

The phase and texture of of Er-germanide formed on Ge͑001͒ through a solid-state reaction between Er thin films and Ge͑001͒ via rapid thermal annealing ͑300-600°C͒ were investigated. It was found that amorphous ErGe 1.2 forms at 300°C, followed by the formation of AlB 2 hexagonal ErGe 1.5 at 400-500°C and then orthorhombic ErGe 1.8 at 600°C. X-ray diffraction pole figure measurement revealed that the ErGe 1.5 films formed at 400-500°C consist predominantly of epitaxial grains with an orientation relationship of ErGe 1.5 ͑11 ¯00͓͒0001͔//Ge͑001͓͒011 ¯͔, although the presence of a considerable amount of epitaxial grains with an orientation relationship of ErGe 1.5 ͑101 ¯2͓͒011 ¯0͔//Ge͑001͓͒010͔ was also observed in the film formed at 400°C. The germanide film formed at 600°C was found to consist of randomly orientated orthorhombic ErGe 1.8 grains. Among the three different germanide phases, ErGe 1.5 showed minimum resistivity values as low as ϳ19 ⍀ cm.

The effect of a small amount of Pt (5 at.%) on the thermal stability of NiSi film on (100)Si and (111 )Si has been investigated. Rutherford back scattering, Scanning Electron Microscopy, and X-ray diffraction have been used to study the formation, microstructure and orientation of the silicide. The addition of platinum results in increasing the disilicide nucleation temperature to 900°C and thus leads to a better stability of NiSi at high IC processing temperatures. The presence of Pt also induced a texture of the NiSi film both on (11 1)Si and (100)Si. The increase in thermal stability is explained in terms of nucleation controlled reaction concept and should open new possibilities for the use of NiSi in self aligned silicidation. The redistribution of Pt in the silicide is examined and explained in terms of kinetics and thermodynamics considerations. The addition of Pt also increases the temperature of agglomeration of NiSi.

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