Raman microprobe spectroscopy measurements of residual stress distribution along blisters in Cr2O3 thin films

Raman spectroscopy has been used to characterise the buckling phenomenon of Cr2O3 films obtained by oxidation in air at 900 °C of Ni33 at%Cr. The observed circular blisters are described by measuring the radius from the optical top view, the profile via an autofocus device and the residual stress in each point of the chromia film: far away from the centre of the blister, in the vicinity and across the blister. The subsequent spalls are related to the morphology of the blisters and to the stress.