Residual Stresses Extraction from Initial Deformation of Multi-Layered Micro-Cantilever

Microelectromechanical systems (MEMS) often consist of multiple layers of diverse materials, each deposited using different techniques, resulting in residual stresses due to growth stress or thermal mismatches. Residual stress significantly impacts the reliability of MEMS devices, potentially leading to delamination or fracture. Therefore, effective methods for determining residual stress are essential, especially for multi-layered structures. This paper introduces a method that combines curvature measurement using white light interferometry (WLI) with a numerical model to progressively predict residual stress in each constituent layer.