Skip to main content

Joining techniques for reliable surface mounting of microelectronics

Objective


This project succeeded in developing a model for predicting the life of solder joints for surface-mounted technology, commonly used in electronic equipment. The prototype model for leadless chip carriers can be used to hope design more reliable electronic assemblies but the results for assemblies using leaded components are not yet accurate enough for reliable prediction. There is considerable scope for industrial applications, ranging from the aviation industry to consumer electronics.
THE FATIGUE FAILURE OF SOLDER JOINTS WHICH RESULTS FROM CYCLIC DEFORMATION CAUSED BY THERMAL EXPANSION MISMATCH BETWEEN SURFACE MOUNTED DEVICES AND THE SUBSTRATES TO WHICH THEY ARE ATTACHED IS ONE OF THE MOST IMPORTANT FACTORS WHICH HAS DELAYED WIDESPREAD UTILISATION OF THIS TECHNOLOGY.
PREVIOUS STUDIES HAVE IDENTIFIED THE FEASIBILITY OF OBTAINING DETAILED SOLDER CHARACTERISATION AND COMPUTER MODELLING TECHNIQUES WHICH WILL ENABLE ELECTRONIC ASSEMBLIES TO BE DESIGNED WITH OPTIMUM PREDICTABLE LIFETIMES.
THE MAJOR OBJECTIVES ARE (1) TO GAIN A DEEPER AND MORE DETAILED UNDERSTANDING OF THE PROPERTIES AND BEHAVIOUR OF THE JOINING MATERIALS (SOLDERS AND CONDUCTIVE ADHESIVES) UNDER THE CONDITIONS OF MANUFACTURE, STORAGE AND USE OF SURFACE MOUNTED MICROELECTRONICS ASSEMBLIES AND (2) TO DEVELOP MATHEMATICAL AND SOFTWARE MODELS FOR DAMAGE ACCUMULATION AND FAILURE MECHANISMS WHICH WILL ENABLE THE CALCULATION OF FAILURE PROBABILITY FUNCTIONS.

Funding Scheme

CSC - Cost-sharing contracts

Coordinator

GEC Alsthom Ltd
Address
Lichfield Road
ST17 4LN Stafford
United Kingdom

Participants (2)

Allgemeine Elektrizitäts Gesellschaft AG (AEG)
Germany
Address
Goldsteinstraße 235
60528 Frankfurt Am Main
FUNDACION INASMET - ASOCIACION DE INVESTIGATION METALURGICA DEL PAIS VASCO
Spain
Address
12,Mikeletegi Pasealekua 2
20009 San Sebastian