Optimisation modelling for design of advanced interconnects

This paper describes a computational strategy for virtual design and prototyping of electronic components and assemblies. The design process is formulated as a design optimisation problem. The solution of this problem identifies not only the design which meets certain user specified requirements but also the design with the maximum possible improvement in particular aspects such as reliability, cost, etc. The modelling approach exploits numerical techniques for computational analysis (Finite Element Analysis) integrated with numerical methods for approximation, statistical analysis and optimisation. A software framework of modules that incorporates the required numerical techniques is developed and used to carry out the design optimisation modelling of fine-pitch flip-chip lead free solder interconnects.

Parallel CFD fire modelling on office PCs with dynamic load balancing

Parallel processing techniques have been used in the past to provide high performance computing resources for activities such as Computational Fluid Dynamics. This is normally achieved using specialized hardware and software, the expense of which would be difficult to justify for many fire engineering practices. In this paper, we demonstrate how typical office-based PCs attached to a local area network have the potential to offer the benefits of parallel processing with minimal costs associated with the purchase of additional hardware or software. A dynamic load balancing scheme was devised to allow the effective use of the software on heterogeneous PC networks. This scheme ensured that the impact between the parallel processing task and other computer users on the network was minimized thus allowing practical parallel processing within a conventional office environment. Copyright © 2006 John Wiley & Sons, Ltd.

Application of modelling for predicting the behaviour of polymers and adhesives in microelectronic and photonic devices

With the growth in computing power, and advances in numerical methods for the solution of partial differential equations, modeling technologies based around computational fluid dynamics, finite element analysis and optimisation are now being widely used by researchers and industry. Polymer and adhesive materials are now being widely used in electronic and photonic devices. This paper will illustrate the use of modeling tools to predict the behaviour of these materials from product assembly to its performance and reliability.

Multi-physics modelling for the fabrication, packaging and reliability of micro-systems components

The latest advances in multi-physics modelling both using high fidelity techniques and reduced order and behavioural models will be discussed. Particular focus will be given to the application and validation of these techniques for modelling the fabrication, packaging and subsequent reliability of micro-systems based components. The paper will discuss results from a number of research projects with particular emphasis on the techniques being developed in a major UK Goverment funded project - 3D-MINTEGRATION (www.3d-mintegration.com).

Multiphysics simulation of microwave processing using a multidomain coupled solver approach

Microwave processing of materials is numerically simulated using a coupled solver approach. Microwave heating is a complex coupled process due to the variation in dielectric properties during heating. The effects of heating an object in a electromagnetic field directly influence the manner in which it interacts with the field. Simplifying assumptions and empirical solutions do not capture the fundamental physics involved and, in general, do not provide usefully accurate solutions in a number of practical problems. In order to capture the underlying processes involved in microwave heating, the problem must be looked at in a holistic manner rather than a number of discrete processes. This contribution outlines a coupled-solver multiphysics analysis approach to the solution of practical microwave heating problems.

Effects of magnetic fields on crystal growth

The effects of a constant uniform magnetic field on thermoelectric currents during dendritic solidification were investigated using an enthalpy based numerical model. It was found that the resulting Lorentz force generates a complex flow influencing the solidification pattern. Experimental work of material processing under high magnetic field conditions has shown that the microstructure can be significantly altered. There is evidence that these effects can be atrtributed to the Lorentz force created through the thermoelectric magentohydrodynamic interactions.[1,2] However the mechanism of how this occurs is not very well understood. In this paper, our aim is to investigate the flow field created from the Lorentz force and how this influences the morphology of dendritic growth for both pure materials and binary alloys.

Convection-diffusion in MHD: Comparison of primitive variable and vector potential solutions of the magnetic induction equation

Abstract not available

Parallelisation of a 3-D electromagnetic scattering code

A high-frequency time domain finite element scattering code using a combination of edge and piecewise constant elements on unstructured tetrahedral meshes is described. A comparison of computation with theory is given for scattering from a sphere. A parallel implementation making use of the bulk synchronous parallel (BSP) programming model is described in detail; a BSP performance model of the parallelized field calculation is derived and compared to timing measurements on up to 128 processors on a Cray T3D.