Three-dimensional Strain and Temperature Mapping of Silicon Using Stimulated Raman Scattering

Three-dimensional integration is vital for advancing high-density electronic and photonic devices, yet managing residual stress and thermal hotspots in silicon (Si) remains a key challenge that impacts performance and reliability. To address this challenge, high-resolution, non-destructive methods capable of probing strain and temperature distributions within bulk Si are critically needed. In this work, we present a long-wavelength stimulated Raman scattering (SRS) microscopy. By employing an Er-doped fiber laser system generating a 1.56 µm pump and a 1.7 µm Stokes beam, we significantly enhance light penetration into Si, enabling accurate localization of mechanical stress and thermal gradients within the bulk.