Residual stresses in aluminum film deposited on a silicon wafer were measured after annealing and quenching. In all cases, residual stresses were tensile, but slow cooling produced larger stresses than quenching. Residual stresses of slow-cooled samples became relaxed after annealing above 300 degrees C. Film passivation by carbon deposition retarded the relaxation of residual stress. in-situ X-ray stress measurement revealed that compressive stresses developed in a heating stage and tensile stresses in a cooling stage. From a scanning electron microscopy observation, it becomes clear that the former contributes to nucleation of hillocks and the latter to void formation and growth.