Intrinsic stress of Co35Pd65 alloy films

Co35Pd65 alloy films were made by the vapor deposition method in a vacuum w ith the base pressure, p, ranging from 3 x 10(-7) to 9 x 10(-5) Torr. The t hickness, t, of these films was varied from 500 to 2500 Angstrom. The subst rate temperature, T-S, was set equal to 50 or 180 degreesC. Some of the as- deposited films were annealed at an anneal temperature T-A from 180 to 350 degreesC in vacuum. We employed a strain gauge to measure the deflection, D elta gamma, of the free end of a cantilevered substrate. The stress, S, of the film was determined while removing the film from the substrate. In gene ral, the stress S of the as-deposited Co35Pd65 film is tensile and of the o rder of 10(9)-10(10) dyn/cm(2). In terms of t dependence, S has a maximum n ear t = 1000 Angstrom. The thermal stress has a small contribution, i.e., S is mainly due to the intrinsic stress formed during film growth. The stres s data are found to be closely associated with the grain structure in these polycrystalline films. Following the same method, we analyzed how S is var ied as a function of T-A. Finally, the effect of the base pressure on S is studied briefly. (C) 2001 American Vacuum Society.