The elastic constants and thermal expansion coefficient of C49 TiSi2 thin films have been investigated by in situ curvature measurement during heat treatment and ex situ x-ray diffraction measurements. The C49 TiSi2 compound was formed from Ti-Si multilayers deposited on monocrystalline silicon and sapphire substrates. The films were polycrystalline without any evident texture. Young’s modulus (142 GPa), Poisson’s ratio (0.27), and the thermal expansion coefficient (10.9×10−6 K−1) have been determined. Note that these values are averages over random crystal orientations. Directly after formation C49 TiSi2 films exhibit tensile stress. This stress relaxes considerably above 375 °C. Below this temperature the thermal expansion is found to be independent of the state of relaxation of the C49 TiSi2 film.

Titanium silicon multilayers have been produced by alternating sputter deposition. The stress in the as-deposited layers is a function of the period of the multilayer structure. The multilayers were subsequently annealed to form silicide films. From stress and strain measurements on these films Poisson’s ratio is determined. After annealing, the films exhibit a tensile stress which can be attributed to the difference in thermal expansion coefficient between substrate and silicide film.

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The thermal expansion coefficient of Al2Cu precipitates embedded in an Al–Cu thin film matrix is determined by in situ x-ray diffraction measurements on free films. The phases present and the thermal expansion or contraction are simultaneously observed during a temperature ramp. The Al2Cu precipitate has a tetragonal structure. The thermal expansion coefficient of the Al2Cu phase in the a direction is significantly smaller than that of the surrounding Al matrix while the thermal expansion in the c direction is comparable to that of the Al matrix. Upon cooling from 500 °C, the mismatch of the thermal expansion between the precipitate and the Al matrix results in compressive and tensile stresses in the aluminum matrix near the precipitates and in compressive stresses in the precipitates. Those stresses are estimated to be on the order of 100 MPa.