Abnormal grain growth in thin Cu films on Si substrates has been investigated as a function of annealing time.Abnormal grains with (110) orientation were observed by transmission electron microscopy. X-ray diffraction patternsshowed that the films which underwent extensive abnormal grain growth also underwent a change in texture from (111)to (100), (110) and (311). A simple theoretical analysis showed that these were the results of a strain-energy-drivenabnormal grain growth process.

In this paper, the effects of grain orientation on preferred abnormal grain growth in metallic films with hcp ((c/a) <1.633)structure have been analyzed with respect to strain energy. The calculated results showed that the lower strain energy densitieswere corresponding to those grains with lower l and higher equaled h and k plane oriented parallel to the plane of the film surface.It was predicted that, from strain energy minimization solely, the preferred orientations or textures in metallic films with hcp(ec=aT < 1:633) structure, such as in a-Ti, a-Zr, a-Hf, Y and Rn, should be with lower l and higher equaled h and k.

In this paper, the effects of grain orientation on preferred abnormal grain growth in HCP-polycrystalline thin films have been analysed with respect to strain energy. The calculated results showed that Chkl, the average values of the orientation factor, decreased with increase of 1 for the same h and k and increased with increase of h or/and k for constant 1. Where (hkl) denoted a particular grain orientation, that is, the grains with (hkl) planes oriented parallel to the film surface. This is preannounced that, considering the strain energy solely, the grains with higher 1 and lower h and k should be favorable in HCP-polycrystalline thin films on rigid substrates after annealing.

Abnormal grain growth in thin Cu films on Si substrates has been investigated as a function of annealing time. Abnormal grains with (110) orientation were observed by transmission electron microscopy. X-ray diffraction patterns showed that the films which underwent extensive abnormal grain growth also underwent a change in texture from (111) to (100), (110) and (311). A simple theoretical analysis showed that these were the results of a strain-energy-driven abnormal grain growth process.

Abnomlal grain growth and texture change in both free standing and attached Ag and Cu fihns after annealing at 300℃ for 2h havebeen investigated with transmission electron microscopy (TEM) and X-ray diffraction (XRD). XRD texture analysis showed that both Ag and Cu fihns deposited on the (001)-oriented single crystal Si snbstrates had (111) and (100) donble fiber textures. 0/20 scmming XRD patterns showed that, after mmealing, the free standing Ag and Cu fihns showed a slight increase in the (111) texture, on the contrary, both Ag and Cu fihns attached on Si snbstrates showed an increase in (100) and (110) textures. Four anomalous large grains with same (211) orientation were observed in attached Cu fihns after annealing by TEM. The experimental resnlts have been explained satisfactorily from anisotropy of surface energy and strain energy.

In this paper, the effects of grain orientation on preferred abnormal grain growth in metallic films with hcp ((c/a)<1.633) structure have been analyzed with respect to strain energy. The calculated results showed that the lower strain energy densities were corresponding to those grains with lower l and higher equaled h and k plane oriented parallel to the plane of the film surface. It was predicted that, from strain energy minimization solely, the preferred orientations or textures in metallic films with hcp ((c=/a<1:633) structure, such as in a-Ti, a-Zr, a-Hf, Y and Rn, should be with lower l and higher equaled h and k.

The microstructural evolution in a thin Cu film with nano-crystallized columnar structure is investigated with transmission electron microscopy (TEM) after being annealed at 250℃ for various times and with computer simulation method. Experimental results show that the average grain size increases linearly with annealing time. A two-dimensional 3-connected network with straight line is assumed and the line tensions acting on vertices are considered only. The simulation results show that, prior to disappearance of small grains, the distribution of angles between lines at vertices tends to 2π/3. The change in grain area for both individual grain and average ones with the same number of sides qualitatively satisfies Von Neumann's law. During the process of disappearance of small grains, the distribution of angles remains similar. However, the distribution of grain shapes (the number of sides) is not time invariant, but broadens with increasing time. The calculation indicates that the average size of grain increases linearly with time. This is consistent with experimental results and can be expected to application in estimating the variation of grain size of thin films at elevated temperature that can be encountered both in post-fabrication and service.

In a previous paper, it was reported that the preferred crystalline orientation of TiO2 transferred significantly from (110) face in starting TiO2 powders to (101) and (111) faces in TiO2 coating deposited on both stainless steel and glass substrates by plasma-sprayedJ. Mater. Sci. Lett. 17 (1998) 1747]. An understanding of the change in the preferred orientations has remained elusive. In this communication, the valence electron structure of TiO2 is established on the basis of Pauling's nature of the chemical bond and the change in the preferred orientations is explained satisfactory.

The surface energies for 38 surfaces of FCC metals Cu, Ag, Au, Ni, Pd, Pt, Al, Pb, Rh and Ir have been calculated by use of the modified embedded-atom method. The results show that, for all FCC metals, as predicted, the close-packed (111) surface has the lowest surface energy. The surface energies for the other surfaces increase linearly with increasing angle between the surfaces (hkl) and (111). This can be used to estimate the relative values of the surface energy.

With modified analytical embedded atom method (MAEAM), the energies of twist grain boundaries (GBs) have been calculated for three noble metals, Cu, Ag and Au with the same FCC structure. The results are similar for all the three metals: (1) the unrelaxed energies keep almost constant with twist angles θ; (2) after expansion perpendicular to the boundary, GB energies drop significantly to less than one-third of their surface energies respectively; (3) in-boundary translation results in periodic energy variation with the period of LS/S, but the energy variation is slight.