Abstract
The performance of an in situ internal stress measurement technique using a Shack-Hartmann sensor (SHS) is examined during nickel electrodeposition in concentrated nickel sulfamate solution. The stress is calculated from the change in the curvature of a test plate bent by stress. The curvature is measured by monitoring the wavefront of an expanded laser beam reflected at the substrate using an SHS. Applying the proposed method, curvature measurements were conducted and the repeatability and accuracy were estimated. In situ stress measurement with a current density of 2.1 mA/cm2 revealed a repeatability of approximately 1 MPa when the thickness of the nickel layer was 19 μm.
