Lee, BW Jeong, JH Jang, W Kim, JY Kim, DW Kwon, D Nah, JW Paik, KW 2024-01-21T09:04:35Z 2024-01-21T09:04:35Z 2021-09-01 2003-04-10 0217-9792 https://pubs.kist.re.kr/handle/201004/138646 Many thermomechanical reliability studies on microelectronics and microsystems have relied upon computational analysis, since experimental work is rather difficult and very time-consuming. For computational analysis, it is essential to use as input accurate material properties; if not, the results of a reliability analysis may be very inaccurate. However, it is still quite difficult to arrive at unified material properties for modeling microelectronic assemblies because of the absence of standards for micro-material characterization, the difference between bulk and in-situ material properties, and so forth. The goal of this study was to determine the uniaxial stress-strain curve of a solder in a flip-chip assembly, using experimental measurements and finite-element analysis (FEA) of the solder's thermal deformation characteristics with increasing temperature. The thermal deformation of flip-chip solder joints was measured by electronic speckle pattern interferometry (ESPI). For the scale of evaluation required, the measurement magnification was modified to allow its application to micromaterials by using a long-working-distance microscope, iris and zoom lens. Local deformation of solder balls could be measured at submicrometer scale, and stress-strain curves could be determined using the measured thermal deformation as input data for finite-element analysis. The procedure was applied to an Sn-36Pb-2Ag flip-chip solder joint. English WORLD SCIENTIFIC PUBL CO PTE LTD Determination of stress-strain curve for microelectronic solder joint by ESPI measurement and FE analysis Article 10.1142/S0217979203019988 1 INTERNATIONAL JOURNAL OF MODERN PHYSICS B, v.17, no.8-9, pp.1983 - 1988 INTERNATIONAL JOURNAL OF MODERN PHYSICS B 17 8-9 1983 1988 scie scopus 000183752800068 Physics, Applied Physics, Condensed Matter Physics, Mathematical Physics Article; Proceedings Paper