Characterization of local strain/stress in copper through-silicon via structures using synchrotron x-ray microdiffraction, electron backscattered diffraction and nonlinear thermomechanical model. (14th July 2015)

• Record Type: Journal Article
• Authors: Song, Ming; Mundboth, Kiran R; Szpunar, Jerzy A; Chen, Li; Feng, Renfei
• Is Part Of: Journal of micromechanics and microengineering. Volume 25:Number 8(2015:Aug.)
• Publication Date: 2015-07-14
• Subjects: through-silicon via (TSV) -- strain -- stress; x-ray microdiffraction -- electron backscattered diffraction (EBSD) -- finite element modeling; Microelectromechanical systems -- Periodicals; Micromechanics -- Periodicals; 621.38105
• DOI: 10.1088/0960-1317/25/8/085002
• Languages: English
• ISSNs: 0960-1317

Abstract

Abstract: In this study, the thermomechanical characteristics of copper through-silicon via (Cu TSV) structures were studied using synchrotron x-ray microdiffraction, electron backscattered diffraction (EBSD), and nonlinear numerical modeling. The strain and stress distribution in the Si substrate was measured by synchrotron x-ray microdiffraction from the tops of the TSV structures. The strain distribution map in a Cu via was determined from EBSD data by the kernel average misorientation (KAM) method and microstructural characteristics of the Cu via were investigated. The results offered direct evaluation of the local strain and stress induced in the Cu via and its surrounding silicon substrate. A finite element model including nonlinear plastic deformation was built for predicting thermomechanical behaviors of Cu TSV structures. The results show that the stress distribution obtained by finite element modeling is in relatively good agreement with the measurements of synchrotron x-ray microdiffraction and EBSD.