Numerical Optimization of Silicon Stacked Module for 3-D Packaging Applications

2008 ◽  
Vol 5 (2) ◽  
pp. 68-76
Author(s):  
Akella G.K. Viswanath ◽  
Xiaowu Zhang ◽  
Y.Y. Wang ◽  
S.W. Yoon ◽  
Navas Khan ◽  
...  
Keyword(s):  
Solder Joint ◽  
Functional Integration ◽  
Three Dimensional ◽  
Interfacial Stress ◽  
Electrical Performance ◽  
Thickness Variation ◽  
Element Analysis ◽  
Variation Of Parameters ◽  
Optimization Study ◽  
Electroplated Copper

Three-dimensional package format has gained more popularity for various applications because of the trend toward higher functional integration, miniaturization, and better electrical performance. This paper presents a design optimization study of a 3-D package using a silicon interposer. The package consists of three stacks with five dies. Electrical connections through the silicon interposers are done by through-silicone vias (TSVs) filled with electroplated copper. Initially, structural optimization of the package is conducted by a 2-D finite element analysis and later, statistical analysis is performed to estimate the coupled effects of parameters considered for the design. Carrier thickness variation is found to be the most significant effect on the package warpage. Interfacial stress between the copper plug and the silicon via hole has been investigated and reported. A 3-D model is constructed for the solder joint reliability study with SnAgCu material properties. Solder joint life with variation of parameters (i.e., board level underfill, higher standoff solder interconnect, and low CTE board) is studied, and all results are reported accordingly.

Reliable Design of Electroplated Copper Through Silicon Vias

2010 ◽  
Author(s):  
Xi Liu ◽  
Qiao Chen ◽  
Venkatesh Sundaram ◽  
Sriram Muthukumar ◽  
Rao R. Tummala ◽  
...  
Keyword(s):  
System Integration ◽  
Coefficient Of Thermal Expansion ◽  
Three Dimensional ◽  
Interfacial Stress ◽  
Through Silicon Vias ◽  
Fabrication Defects ◽  
Reliable Design ◽  
Electroplated Copper ◽  
Key Enabling Technologies ◽  
Silicon Vias

Through-silicon vias (TSVs), being one of the key enabling technologies for 3D system integration, are being used in various 3D vertically stacked devices. As TSVs are relatively new, there is not enough information in available literature on the thermo-mechanical reliability of TSVs. Due to the high coefficient of thermal expansion (CTE) mismatch between Si and the Cu vias, “Cu pumping” will occur at high temperature and “Cu sinking” will occur at low temperature, which may induce large stress in SiO2, interfacial stress at Cu/SiO2 interface and plastic deformation in Cu core. The thermal-mechanical stress can potentially cause interfacial debonding, cohesive cracking in dielectric layers or Cu core, causing some reliability issues. Thus, in this paper, three-dimensional thermo-mechanical finite-element models have been built to analyze the stress/strain distribution in the TSV structures. A comparative analysis of different via designs, such as circular, square, and annular vias has been performed. In addition, defects due to fabrication such as voids in the Cu core during electroplating and Cu pad undercutting due to over-etching are considered in the models, and it is seen that these fabrication defects are detrimental to TSV reliability.

A Three-Dimensional Finite Element Analysis with Various Implant Designs

2007 ◽  
Vol 342-343 ◽  
pp. 885-888
Author(s):  
Dong Ki Yoo ◽  
Seong Joo Heo ◽  
Jai Young Koak ◽  
Seong Kyun Kim ◽  
Young Jun Lim ◽  
...  
Keyword(s):  
Stress Distribution ◽  
Three Dimensional ◽  
Interfacial Stress ◽  
Initial Contact ◽  
Implant Surface ◽  
Element Analysis ◽  
Wide Diameter ◽  
Initial Stability ◽  
Dimensional Finite Element ◽  
Three Dimensional Finite Element

Various studies recommend that threaded type implants should be used to maximize initial contact, improve initial stability, enlarge implant surface area, and favor dissipation of interfacial stress. The objective of this study was to compare four types of screw implants placed in posterior region of mandible model and evaluate the influences of implant shape, configuration, length, diameter and abutment connection method on stress distribution using a three-dimensional finite analysis. Four types of two-length implant models — 8.5 and 13 mm — were selected and the wide diameter was also used. Four groups were classified by implant outline and connection manner A load of 100 N was applied vertically on the center of the implant. Oblique and horizontal loads were taken as equal to that of the vertical load. The TMJ area in mandibular model was constrained in all directions. Results show that the stress of two-length implants was similar in all groups and the internal connection implant with appropriate thickness of inner part of the implant had better stress distribution.

Numerical Analysis of Thermoelastic Instability in Disc Brake System

2011 ◽  
Vol 110-116 ◽  
pp. 2780-2785 ◽  
Author(s):  
Sung Pil Jung ◽  
Hyun Seok Song ◽  
Tae Won Park ◽  
Won Sun Chung
Keyword(s):  
Three Dimensional ◽  
Mechanical Analysis ◽  
Brake System ◽  
Thickness Variation ◽  
Disc Brake ◽  
Friction Contact ◽  
Analysis Model ◽  
Element Analysis ◽  
Thermoelastic Instability ◽  
Analysis Technique

Thermal energy generated by the friction between the disc and pad is transferred to both components and causes thermal expansion of material of each component, and futher affects the friction contact condition. This is the main factor of the thermoelastic instability (TEI) of a disc brake. In this study, TEI is analyzed using the finite element analysis technique. Three dimensional thermo-mechanical analysis model of the disc brake system is created. An intermediate processor based on the staggered approach is used to exchange analysis results: temperature, friction contact power, nodal displacement and deformation. Disc thickness variation (DTV) and temperature distribution of the disc are calculated, and the tendency and meaning of the results are discussed.

scholarly journals Free and Forced Vibration of Laminated and Sandwich Plates by Zig-Zag Theories Differently Accounting for Transverse Shear and Normal Deformability

Aerospace ◽  
2018 ◽  
Vol 5 (4) ◽  
pp. 108 ◽  
Author(s):  
Ugo Icardi ◽  
Andrea Urraci
Keyword(s):  
Transverse Shear ◽  
Degrees Of Freedom ◽  
Three Dimensional ◽  
Interfacial Stress ◽  
Sandwich Plates ◽  
Displacement Fields ◽  
Element Analysis ◽  
Out Of Plane ◽  
Elasticity Solutions ◽  
Displacement Based

A number of mixed and displacement-based zig-zag theories are derived from the zig-zag adaptive theory (ZZA). As a consequence of their different assumptions on displacement, strain, and stress fields, and layerwise functions, these theories account for the transverse shear and normal deformability in different ways, but their unknowns are independent of the number of layers. Some have features that are reminiscent of ones that have been published in the literature for the sake of comparison. Benchmarks with different length-to-thickness ratios, lay-ups, material properties, and simply supported or clamped edges are studied with the intended aim of contributing toward better understanding the influence of transverse anisotropy on free vibration and the response of blast-loaded, multilayered, and sandwich plates, as well as enhancing the existing database. The results show that only theories whose layerwise contributions identically satisfy interfacial stress constrains and whose displacement fields are redefined for each layer provide results that are in agreement with elasticity solutions and three-dimensional (3D) finite element analysis (FEA) (mixed solid elements with displacements and out-of-plane stresses as nodal degrees of freedom (d.o.f.)) with a low expansion order of polynomials in the in-plane and out-of-plane directions. The choice of their layerwise functions is shown to be immaterial, while theories with fixed kinematics are shown to be strongly case-sensitive and often inadequate (even for slender components).

Finite Element Analysis for Wall Thickness Variation of Seamless Tube in Stretch Reducing Rolling Process

2011 ◽  
Vol 291-294 ◽  
pp. 532-536 ◽  
Author(s):  
Hui Yu ◽  
Yong Chen ◽  
Xiang Zhong Bai
Keyword(s):  
Finite Element Analysis ◽  
Finite Element ◽  
Wall Thickness ◽  
Three Dimensional ◽  
Longitudinal Direction ◽  
Rolling Process ◽  
Thickness Variation ◽  
Analysis Model ◽  
Element Analysis ◽  
Wall Thickness Variation

According to the geometrical characteristic of workpiece and groove in the stretch reducing rolling process, three-dimensional elastic-plastic finite-element analysis model was established to simulate the metal deformation, the regularities of distribution of wall thickness of transverse direction longitudinal direction were investigated. The analysis was verified by comparing finite element analysis results with on-line measurements. The length of crop ends was determined as well as product bore polygonization. The study provides the foundation for analyzing product defeat and instructing technological design.

Effects of occlusal scheme on All-on-Four abutments, screws and prostheses: A three-dimensional finite element study

2020 ◽  
Author(s):  
Nurullah Türker ◽  
Hümeyra Tercanlı Alkış ◽  
Steven J Sadowsky ◽  
Ulviye Şebnem Büyükkaplan
Keyword(s):  
Finite Element ◽  
Three Dimensional ◽  
Good Prognosis ◽  
Von Mises Stress ◽  
Element Analysis ◽  
Group Function ◽  
Occlusal Contact ◽  
Maximum Deformation ◽  
Contact Points ◽  
Von Mises

An ideal occlusal scheme plays an important role in a good prognosis of All-on-Four applications, as it does for other implant therapies, due to the potential impact of occlusal loads on implant prosthetic components. The aim of the present three-dimensional (3D) finite element analysis (FEA) study was to investigate the stresses on abutments, screws and prostheses that are generated by occlusal loads via different occlusal schemes in the All-on-Four concept. Three-dimensional models of the maxilla, mandible, implants, implant substructures and prostheses were designed according to the All-on-Four concept. Forces were applied from the occlusal contact points formed in maximum intercuspation and eccentric movements in canine guidance occlusion (CGO), group function occlusion (GFO) and lingualized occlusion (LO). The von Mises stress values for abutment and screws and deformation values for prostheses were obtained and results were evaluated comparatively. It was observed that the stresses on screws and abutments were more evenly distributed in GFO. Maximum deformation values for prosthesis were observed in the CFO model for lateral movement both in the maxilla and mandible. Within the limits of the present study, GFO may be suggested to reduce stresses on screws, abutments and prostheses in the All-on-Four concept.

Towards Predicting Relative Belt Edge Endurance With the Finite Element Method

1990 ◽  
Vol 18 (4) ◽  
pp. 216-235 ◽  
Author(s):  
J. De Eskinazi ◽  
K. Ishihara ◽  
H. Volk ◽  
T. C. Warholic
Keyword(s):  
Finite Element Method ◽  
Finite Element ◽  
Three Dimensional ◽  
The Finite Element Method ◽  
Shear Deformations ◽  
Element Analysis ◽  
Vertical Loading ◽  
Predicted Values ◽  
Element Method

Abstract The paper describes the intention of the authors to determine whether it is possible to predict relative belt edge endurance for radial passenger car tires using the finite element method. Three groups of tires with different belt edge configurations were tested on a fleet test in an attempt to validate predictions from the finite element results. A two-dimensional, axisymmetric finite element analysis was first used to determine if the results from such an analysis, with emphasis on the shear deformations between the belts, could be used to predict a relative ranking for belt edge endurance. It is shown that such an analysis can lead to erroneous conclusions. A three-dimensional analysis in which tires are modeled under free rotation and static vertical loading was performed next. This approach resulted in an improvement in the quality of the correlations. The differences in the predicted values of various stress analysis parameters for the three belt edge configurations are studied and their implication on predicting belt edge endurance is discussed.

Torsional Analysis of a Steel Cord-Rubber Tire Belt Structure

1996 ◽  
Vol 24 (4) ◽  
pp. 339-348 ◽  
Author(s):  
R. M. V. Pidaparti
Keyword(s):  
Finite Element ◽  
Finite Element Model ◽  
Composite Structures ◽  
Three Dimensional ◽  
Element Model ◽  
Torsional Stiffness ◽  
Element Analysis ◽  
Rubber Belt ◽  
Steel Cord ◽  
Torsional Analysis

Abstract A three-dimensional (3D) beam finite element model was developed to investigate the torsional stiffness of a twisted steel-reinforced cord-rubber belt structure. The present 3D beam element takes into account the coupled extension, bending, and twisting deformations characteristic of the complex behavior of cord-rubber composite structures. The extension-twisting coupling due to the twisted nature of the cords was also considered in the finite element model. The results of torsional stiffness obtained from the finite element analysis for twisted cords and the two-ply steel cord-rubber belt structure are compared to the experimental data and other alternate solutions available in the literature. The effects of cord orientation, anisotropy, and rubber core surrounding the twisted cords on the torsional stiffness properties are presented and discussed.

Finite Element Modeling for Steel Cord Analysis in Radial Tires

2013 ◽  
Vol 41 (1) ◽  
pp. 60-79 ◽  
Author(s):  
Wei Yintao ◽  
Luo Yiwen ◽  
Miao Yiming ◽  
Chai Delong ◽  
Feng Xijin
Keyword(s):  
Finite Element ◽  
High Efficiency ◽  
Force Measurement ◽  
Three Dimensional ◽  
Local Stress ◽  
Tension Force ◽  
Center Line ◽  
Element Analysis ◽  
Design Variables ◽  
Steel Cord

ABSTRACT: This article focuses on steel cord deformation and force investigation within heavy-duty radial tires. Typical bending deformation and tension force distributions of steel reinforcement within a truck bus radial (TBR) tire have been obtained, and they provide useful input for the local scale modeling of the steel cord. The three-dimensional carpet plots of the cord force distribution within a TBR tire are presented. The carcass-bending curvature is derived from the deformation of the carcass center line. A high-efficiency modeling approach for layered multistrand cord structures has been developed that uses cord design variables such as lay angle, lay length, and radius of the strand center line as input. Several types of steel cord have been modeled using the developed method as an example. The pure tension for two cords and the combined tension bending under various loading conditions relevant to tire deformation have been simulated by a finite element analysis (FEA). Good agreement has been found between experimental and FEA-determined tension force-displacement curves, and the characteristic structural and plastic deformation phases have been revealed by the FE simulation. Furthermore, some interesting local stress and deformation patterns under combined tension and bending are found that have not been previously reported. In addition, an experimental cord force measurement approach is included in this article.

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