Techniques are described for the production of fluorine-18 labeled I-IF etches and their use in the study of the retention of fluoride on silicon and silicon dioxide surfaces. Results are presented that show fluoride is retained by a chemical adsorption mechanism.
A study has been performed to determine the impact of package assembly on shear stress phenomena in plastic encapsulated integrated circuits (Ie's). Test structures were used which allowed quantitative measurements of compressive stresses along with qualitative observation of shear stress effects. Results from experiments with various mold compounds, lead frame materials, and mount compounds will be presented. The experiments led to the development of a simplified stress model which can be applied to evaluating package and chip designs of future products.
The phenomenon of package cracking during solder reflow continues to trouble surface mount plastic packages for integrated circuits (ICs). The mechanism has been explained as moisture absorption, vaporization, delamination (loss of adhesion), deformation, and final package cracking. The effect of diminished mold compound material properties in saturated moisture and elevated temperature environments is a crucial factor. Current specifications of flexural strength at room temperature and elevated temperature flexural strengths for mold compounds do not correlate well with known failures during reliability/qualification preconditioning tests. Characterization of mold compound using uniaxial tensile tests have furthered the understanding of the mechanical nature of the material.
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.