Changes in residual stress, crystallite size, microstrain and texture of 50 nm thick sputter-deposited polycrystalline Cu and Ni thin films with temperature have been investigated employing in-situ X-ray diffraction measurements in a temperature range between 25°C and 250°C. Stress determinations were performed by analyzing the X-ray diffraction data according to the sin2ψ-method on the basis of the crystallite group variant. It has been found that grain growth in both layers is accompanied by the emergence of a considerable tensile stress component parallel to the surface. The stress evolutions in the layers were correlated with the changes of their coherently diffracting domain sizes and microstrains with temperature. The advantages of additional measurements at temperatures below ambient temperature to distinguish the thermal stresses from effects of stress relaxation and emerging secondary stresses, arising from thermally activated processes (such as grain growth) are emphasized.
The obtained results on grain growth and stress evolution are discussed in the light of different grain growth models. The excess volume in grain boundaries has been determined from the evolution of the residual stress and crystallite size with temperature.