Stresses and strain in silicon: 3-dimensional analytical capabilities for the non-invasive evaluation of strain fields in Si wafers and packaged chips

IC manufacturing and chip embedding processes can induce stresses in Si, which have the potential to affect device functionality and reliability and ultimately lead to device failure. One of the challenges for the future of semiconductor manufacturing and chip packaging is the development of non-destructive metrology both at wafer level, and post-packaging. In this context this thesis proposes novel techniques for the in situ imaging of strain and internal damage in processed Si wafers and packaged Si chips. X-Ray Diffraction Imaging (XRDI) is a powerful, non-destructive technique for the imaging of strain in crystalline materials. Traditionally, section transmission topography geometry has been used to image the crystal volume and obtain direct information on the depth of defects present; however these images provide information on only a small volume of the crystal and can be difficult to interpret. In this thesis two novel 3-dimensional characterisation techniques based on XRDI are presented; 3-dimensional x-ray diffraction imaging (3D-XRDI) and 3-dimensional surface modelling (3DSM). The development and application of 3D-XRDI and 3DSM for the in situ imaging of strain and internal damage in processed Si wafers and packaged Si chips is demonstrated