In order to improve the sensitivity of stress measurement using an electroplated copper film, mechanical properties of the film was measured using a scanning blue-laser microscope. The Young's modulus of the film was about a fourth of that of bulk material, and the tensile strength of the film was about 30% higher than that of bulk material. The surface roughness of the film after cyclic loading was about a tenth of that before loading. Formation of micro slits, 50μm long and 6 μm wide, in the film improved the sensitivity of the stress measurement. The minimum stress that causes the changes of the film texture after 10^8 cycle load decreased from 100MPa to 30MPa.