... CTE or nonconsidering residual strain, especially for temperature above T g . 02 12 2010 30 09 2011 09 12 2011 09 12 2011 electronics packaging encapsulation plates (structures) polymers stress-strain relations viscoelasticity thermomechanical analysis...

... to be effective in alleviating thermal stresses and improving solder joint fatigue performance in thermal cycling tests of long-time scale, underfill material viscoelasticity is ineffective in attenuating short-time scale propagating shock waves. In addition, the inclusion of Cu interconnecting layers in flip...

...Fang Liu; Guang Meng; Mei Zhao Dynamic properties of printed circuit board (PCB) assembly under drop impact are investigated when viscoelasticity of substrate materials is considered. The main materials of a PCB substrate are macromolecule resins, which are typical viscoelastic materials. From...

... characterized. In this paper, we present extensive experimental data on thermally and UV-cured epoxies, typically used in photonic packages to enable stochastic analysis. We perform dynamic mechanical analysis over a wide frequency and temperature range to determine the viscoelastic behavior of the epoxies. We...

...) simulation. Viscoelastic models for adhesives and underfill materials were employed, and the comparison with an elastic model was made. Calculated equivalent stresses S eqv and shear stress σ x y fitted well with the experimental lifetime measurement, thus a lifetime relationship similar to the Coffin-Manson...

... interconnections indentation hardness hardness testing viscoelasticity thermomechanical treatment The copper/low- k material configuration in the interconnect structures of today’s advanced microchips often exhibits thermo-mechanical failure during fabrication or packaging. Low- k...

... Microelectronics Micro Lead Frame Packaging Perzyna Rigid Plastic Solder Joints Shape Standoff Height Surface Evolver Viscoplastic Von Mises Warpage ball grid arrays integrated circuit reliability viscoelasticity reflow soldering surface tension wetting finite element analysis 18 04...

...., 1975 , The Physics of Metals 2. Defects , Cambridge University Press , Cambridge, UK. Gittus , J. , 1975 , Creep, Viscoelasticity and Creep Fracture in Solids , Applied Science Publishers , London. Cadek , J. A. , 1988 , Creep in Metallic Materials , Elsevier , Amsterdam...

... for the integrity and reliability of the interconnect during processing, testing, and use. Being a polymer, SiLK may show viscoelastic (time-dependent) behavior. In this paper, we use nanoindentation techniques in combination with analytical and finite element modeling (FEM) to determine the viscoelastic properties...

...Ji Hyuck Yang; Kang Yong Lee The purposes of the paper are to consider the failure phenomenon by delamination and crack when the encapsulant of plastic IC package under hygrothermal loading in the IR soldering process shows elastic and viscoelastic behaviors and to suggest the optimum design...

..., with both step-function and sinusoidal temperature histories being considered. The time-dependent effects in the array’s shear deformation are introduced in an approximate manner by modeling the interconnect material (solder) as a temperature-independent linear viscoelastic material. The viscoelastic...

... of the molding compound. FE models which incorporate the viscoelastic constitutive relation of the material are constructed to simulate the thermo-mechanical stresses caused by the packaging processes. The influences of both the chip anisotropy and the viscoelastic behavior of the molding compound...

... experimentally for various kinds of substrate and the thickness of an integrated circuit using a laser beam. In particular, a simple theory on the basis of a multilayered plate theory considering a viscoelastic property in the substrate is presented, and the thermo-viscoelastic analysis for the deflection of CSP...

... observation, and cross section inspection. The corresponding 3-D finite element simulation was performed to analyze the effects of underfill on thermomechanical behavior. The viscoelasticity of underfill and the viscoplasticity of solder were considered in the 3-D simulations. The Coffin-Manson equation...

...D. Ingman; Y. Michlin A nonlinear viscoelastic damage accumulation model with a physical approach is presented with a view to describing stress relaxation in amorphous and partially crystalline polymers. The deformation is represented as stress-aided transition through a series of symmetrical...

.... L., Caers, J. F. J., Boer, A. W. J. den, and Janssen, J., 2000, “Mechanical characterization and simulation of packaging polymer curing,” Proc. of the 3th Int. Conf. on Micro Materials, MicroMat 2000, Berlin, Apr.. Kiasat, M. S., 2000, “Curing Shrinkage and Residual Stresses in Viscoelastic...

... method for predicting the thin small outline packages (TSOP) warpage. The results indicate that viscoelastic-GK calculation with relaxation of shear modulus and of bulk modulus using the multilayer shell element is the most appropriate method for predicting the warpage. All calculations confirm...

..., the material is modeled as viscoelastic and temperature-independent. This permits one to invoke the correspondence principle of viscoelasticity to map the authors’ previously derived, closed-form solution for an elastic nonprismatic (concave, convex, or cylindrical) Timoshenko beam under shear loading...

... understanding of epoxy molding compound (EMC) properties with molding parameters is necessary as EMC is epoxy-based with time and temperature dependent viscoelastic properties. This paper first addressed the thermal characterization of encapsulating material. Degree-of-cure (DOC or β), coefficient of thermal...