Thickness-dependent fcc–hcp phase transformation in polycrystalline titanium thin films

{111} fiber textured face centered cubic (fcc) titanium has been found to coexist with the {0002} fiber textured hexagonal close packed (hcp) titanium in polycrystalline titanium (Ti) thin films (thickness: 144 nm to 720 nm) deposited on Si (100) substrate by magnetron sputtering. X-ray diffraction investigation confirms that relative phase fraction of such metastable fcc Ti phase decreases with increasing film thickness indicating thickness dependent fcc-hcp phase transformation of titanium. Texture development in hcp Ti phase was due to film microstructure (thickness effect) rather than the phase trans-formation. Diffraction stress analysis (by d-sin2 method) indicates that fcc to hcp phase transformation is also accompanied by the reduction of compressive stress in the hcp Ti phase with increasing film thickness. Strain energy calculations for both phases of titanium indicate that fcc Ti is a more stable phase compared to hcp Ti at relatively low film thickness (144 nm to 432 nm). It has been concluded that film stress favours fcc to hcp phase transformation towards the higher film thickness. Reverse transformation (hcp to fcc) occurs towards the lower film thickness.

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Electron-irradiation-induced phase transformation and fractional volatilization in (Mg, Fe) 2 SiO 4 olivine thin films

Philosophical Magazine A ◽

10.1080/01418610110053865 ◽

2001 ◽

Vol 81 (12) ◽

pp. 2823-2840 ◽

Cited By ~ 1

Author(s):

Philippe Carrez, Hugues Leroux, Patrick Cord

Keyword(s):

Thin Films ◽

Phase Transformation ◽

Electron Irradiation

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Phase transformation and preferred orientation in carboxylate derived ZrO2 thin films on silicon substates

Journal of Materials Research ◽

10.1557/jmr.1992.3065 ◽

1992 ◽

Vol 7 (11) ◽

pp. 3065-3071 ◽

Cited By ~ 4

Author(s):

Peir-Yung Chu ◽

Isabelle Campion ◽

Relva C. Buchanan

Keyword(s):

Thin Films ◽

Heat Treatment ◽

Phase Transformation ◽

Heating Rate ◽

Tetragonal Phase ◽

Monoclinic Phase ◽

Preferred Orientation ◽

Si Substrate ◽

Interfacial Diffusion ◽

Deposited Films

Phase transformation and preferred orientation in ZrO2 thin films, deposited on Si(111) and Si(100) substrates, and prepared by heat treatment from carboxylate solution precursors were investigated. The deposited films were amorphous below 450 °C, transforming gradually to the tetragonal and monoclinic phases on heating. The monoclinic phase developed from the tetragonal phase displacively, and exhibited a strong (111) preferred orientation at temperature as low as 550 °C. The degree of preferred orientation and the tetragonal-to-monoclinic phase transformation were controlled by heating rate, soak temperature, and time. Interfacial diffusion into the film from the Si substrate was negligible at 700 °C and became significant only at 900 °C, but for films thicker than 0.5 μm, overall preferred orientation exceeded 90%.

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