Research advances in nano-composite solders

Recently, nano-composite solders have been developed in the electronic packaging materials industry to improve the creep and thermo-mechanical fatigue resistance of solder joints to be used in service at high temperatures and under thermo-mechanical fatigue conditions. This paper reviews the driving force for the development of nano-composite solders in the electronic packaging industry and the research advances of the composite solders developed. The rationale for the preparation of nano-composite solders are presented at first. Examples of two nano-composite solder fabrication methods, a mechanical mixing method and an in-situ method, are explained in detail. The achievements and enhancements in the nano-composite prepared solders are summarized. The difficulties and problems existing in the fabrication of nano-composite solders are discussed. Finally, a novel nano-structure composite solder, which attempts to solve the problems encountered in the fabrication of nano-composite solders, is introduced in detail. Guidelines for the development of nano-composite solders are then provided. (C) 2008 Elsevier Ltd. All rights reserved.