A finite element approach to nonlinear thin shell analysis

A Finite Strain Shell Model for the Analysis of Moderately Thick-Walled Tubes

Time-Dependent Behaviour of Polymers and Unidirectional Polymeric Composites

Micromechanical modelling of the transverse strengths of unidirectional glass-fibre reinforced polyester

A time-dependent constitutive model for filled and vulcanized rubbers.

On the prediction of damage and fracture strength of notched composites

Mechanical characterization and modeling of curing thermosets

Chemical shrinkage and simultaneous build-up of mechanical properties in curing thermosets leads to the build-up of residual stresses and strains. Depending on the constraints these may cause interface failure, dimensional inaccuracy or failure in the thermoset or its surrounding structure. The present work aims at both an improved methodology...

Cure-Dependent Viscoelastic Behaviour of Electronic Packaging Polymers: Modelling, Characterization, Implementation and Applications

Polymers are widely used in electronic packaging as encapsulants, underfills, adhesives, insulators, and dielectrics, etc. Generally these materials are thermosetting polymers that have to be cured during the fabrication process at elevated temperatures. The curing process will introduce residual stress and warpage in the microelectronic devices...

Virtual thermo-mechanical prototyping of microelectronics devices

Microelectronics have pervaded our lives for the past fifty years, with massive penetration into health, mobility, safety and security, communications, education, entertainment and virtually every aspect of human lives. The main technology drivers that enabled this expansion are miniaturization and integration. The combination of these two has...

Mechanical Characterization of Flexible and Stretchable Electronic Substrates

Conventional IC packages form a rigid shell around silicon IC dies. Their purpose is to provide environmental protection, electrical interconnect and heat dissipation. Despite the fact that majority of current silicon IC?s are realized in a very thin top layer of the silicon substrate (<10µm), the typical thickness of packaged IC dies generally...

Tailoring of epoxy material properties

This research work is aimed to understand the effect of resin chemistry on the physical properties (e.g. moduli, viscoelasticity, moisture uptake, coefficient of thermal expansion) of cured aromatic epoxy-amine thermoset resins. This understanding will result into a good first approximation of the final properties. As a consequence in future it...

The effect of aging on molding compound properties

High-speed Impact Modelling and Testing of Dyneema Composite

Dyneema (Ultra High Molecular Weight Polyethylene – UHMW PE) is a high performance material that is used in many applications. These applications vary from leisure articles such as sails and kite wires to surgical wires and personal protection products. The reason that Dyneema outperforms many other materials is that it possesses a combination...

Reliability at the Chip Interfaces: Delaminating the Silicon Die from Molding Compound

This book describes a setup that allows to delaminate the Silicon-to-Molding Compound interface for obtaining interfacial fracture parameters: the Mixed Mode Chisel setup (MMC). With this device for the first time the delamination can be initiated and propagated, while preventing the occurrence of random brittle fracture in one or both of the...

Failure and Delamination in Microelectronic Packages

Thin layers of dissimilar materials are used in most microelectronic components in order to achieve special functional requirements. Generally, the interface between two adjacent materials forms a weak link, not only because of the relatively low delamination strength, but also because of the existing mismatch in thermo-mechanical properties,...

Surface Modification of Titanium and Polyimide Sheet for Adhesive Bonding

Major industrial sectors like automotive, aerospace and others are increasingly using polymer composites in their structural parts. Polyimide sheet and adhesives, are high performance polymers. They are widely used in various engineering applications due to their excellent thermal, mechanical and chemical properties and their resistance to...

On the nonlinear thermomechanical behavior and delamination of conductive adhesives

Adhesives based on thermoset polymers are used as thermal and electrical interfaces. These adhesives are filled with different particles in order to meet the requirements of heat transfer and electrical properties. Due to the reliability requirements of automotive applications, they are required to have excellent bulk and interface properties....

Numerical Analysis and Experimental Verification of Stresses Building up in Microelectronics Packaging

This thesis comprises a thorough study of the microelectronics packaging process by means of various experimental and numerical methods to estimate the process induced residual stresses. The main objective of the packaging is to encapsulate the die, interconnections and the other exposed internal components by providing mechanical protection,...