Nitrogen ions ( N2 +) with 62 keV have been implanted into 100-nm-thick Ti films evaporated on thermally cleaned NaCl substrates. Unimplanted and N-implanted Ti films have been examined by transmission electron microscopy, Rutherford backscattering spectrometry and elastic recoil detection analysis. The analysis has provided evidence that N-implantation results in the epitaxial formation of NaCl-type TiN y and simultaneously induces the release of H from evaporated-Ti films containing TiH x . The nitriding of evaporated-Ti films is mainly divided into two elemental processes. One is accompanied by the hcp-fcc transformation and the other is not. The formation mechanism for TiN y is discussed.

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The depth profiles of hydrogen concentration in Ti-evaporated films on NaCl substrates have been measured with the elastic recoil detection analysis technique using a 2.7 MeV 4He+ beam. It has been revealed that the Ti film absorbs hydrogen escaped from the substrate. The hydrogen concentration in the film decreased with increasing substrate temperature. It is pointed out that the epitaxial growth of substances with a great affinity for hydrogen, evaporated on NaCl or deliquescent alkali halide substrates, should be re-examined from the point of view of hydrogenation on the substrate.

The α-Sn (111) films of 150 monolayers (ML) will grow at room temperature on thermally cleaned InSb (1̄1̄1̄) substrates having a 2×2 reconstructed surface. The α-Sn (111) surfaces are observed to most clearly exhibit a 3×3 reconstruction at a film thickness of 30 ML by reflection high energy electron diffraction (RHEED). When the 30 ML films are heated at 170°C, the liquid phase begins to appear without the transition to the β-phase. From these result, effects of the InSb (1̄1̄1̄) substrate on the thermal stability of the α-Sn (111) film are discussed.

Thin films of Au were deposited onto MgO substrates cleaved in ultrahigh vacuum. The films, which were examined by transmission electron microscopy and electron diffraction, did not grow with a (111) orientation observed in a Au/NaCl system but with a (100) orientation which had been observed in a Pd/MgO system. In order to obtain some insight into the differences in the epitaxial orientations, we studied interfacial chemical bonding states in Au/MgO(100), Pd/MgO(100), and Au/NaCl(100) systems using total pair-potential calculations and discrete variational Xα calculations. The results show that interfacial interaction in both the Au/MgO and the Pd/MgO system is stronger than that in the Au/NaCl system. The relation between the strength of the interfacial chemical bond and the epitaxial orientation in the above systems is discussed.