We present an improved photoreflectance (PR) spectroscopy technique upon the prior art in providing a rapid acquisition method of the PR spectrum in a simultaneous and multiplexed manner. Rapid PR (RPR) application is the on-line monitoring of strained silicon. Shrinkage in the silicon bandgap is measured and converted to strain, using theoretical models. Experimental RPR results are in good correlation with Raman spectroscopy.
In this paper we demonstrate the application of Digital Image Correlation (DIC) to the measurement of nanometer scale deformation in advanced packaging including flip chip and stacked integrated circuit dies. The application of DIC is shown to provide critical strain data which is useful for lifetime prediction of advanced packaging solutions. We show U and V deformation field contour (fringe) maps, analogous to Moiré interferometry results, measured by digital image correlation technology, without the need for applied phase gratings. Shear and normal strain contour maps are also shown superimposed transparently on micrograph images.Novel enhancements of the digital image correlation technique are described with particular emphasis on the refinement of the technique for application to electronics package measurement, and on software development. The application of levels of intelligent, goodness-of-data based corrections, for the measurement of nanometre scale deformation, and rigid body motion corrections are discussed. The technique has been further refined to obtain measurements from entire IC package structures which include such thermally and optically distinct materials as underfill and copper layers.Finally, failure analysis and modeling, such as NorrisLandzberg or Coffin-Manson models, is discussed in relation to the results exposed in this paper.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.