Residual Strain in Deuterated Ti Thin Films

Phase structure, texture and residual strain field in thin films of titanium deposited on left angle bracket100right-pointing angle bracketSi by e-beam evaporation in the presence of a low pressure deuterium atmosphere, were studied by X-ray diffraction (XRD). XRD measurements and traditional data interpretation were modified to properly account for the highly textured grain structure. In fact, depending on the deposition temperature (TD), Ti thin films were cubic (TD=150°C) or hexagonal (TD>150°C), but they invariably showed a strong texture along the growth direction: [111] and [002] for the cubic and the hexagonal films (TD=450°C), respectively. The residual in-plane strain was tensile, mainly of thermal nature, due to the difference in thermal expansion between Ti–D phases and Si substrate.