ASPECTS OF RESIDUAL-STRESS MEASUREMENTS IN TIN PREPARED BY REACTIVE SPUTTERING

In earlier work it has been shown that the residual stress in the plane of films prepared by reactive sputtering depends not only on the substrate bias and magnetron input power, but also on the crystal plane (i.e. the individual crystals and their orientation) on which it is measured. Existing data in the scientific literature indicate that there is a correlation between the microhardness and the residual stress or the strain distribution. In the present work the correlation between these properties is studied and the data indicate that there are two regimes. In the first, the residual stress and strain distribution increase together with an increase in the microhardness; in the second, the microhardness seems to reach a maximum as does the residual stress, but the strain distribution continues to increase with target power. It is suggested that these maxima may correspond to the maximum in work hardening observed in metals.