This book highlights recent research progress in lead (Pb)-free solder technology, focusing on materials development, processing, and performances. It discusses various Pb-free solder materials’ development, encompassing composite solders, transient liquid phase sintering, and alloying. The book also details various Pb-free solder technology processing and performances, including flux modification for soldering, laser soldering, wave soldering, and reflow soldering, while also examining multiple technologies pertaining to the rigid and flexible printed circuit board (PCB). Some chapters explain the materials characterization and modeling techniques using computational fluid dynamics (CFD). This book serves as a valuable reference for researchers, industries, and stakeholders in advanced microelectronic packaging, emerging interconnection technology, and those working on Pb-free solder.

This book is about solders and their composition and focuses on material characterizations and the methods used to make alloys and determine their structures, physical properties and applications. Physical properties and the factors that control them and theoretical verification are the main contents of this book. Corrosion of solders is included in the coverage of the properties related to solder composition and mechanical properties.

The book is important because it reflects a trend, especially in microelectronics manufacture toward recyclability. Europe and Asia are moving towards legislation to ban the use of lead in solders and public demand in the US will likely have the same result. Producers of solders and manufacturers who use them will have to invent and employ suitable substitutes and A Guide to Lead-free Solders will show them how to do so.

Providing a viable alternative to lead-based solders is a major research thrust for the electrical and electronics industries - whilst mechanically compliant lead-based solders have been widely used in the electronic interconnects, the risks to human health and to the environment are too great to allow continued widescale usage. Lead-free Solders: Materials Reliability for Electronics chronicles the search for reliable drop-in lead-free alternatives and covers: Phase diagrams and alloy development Effect of minor alloying additions Composite approaches including nanoscale reinforcements Mechanical issues affecting reliability Reliability under impact loading Thermomechanical fatigue Chemical issues affecting reliability Whisker growth Electromigration Thermomigration Presenting a comprehensive understanding of the current state of lead-free electronic interconnects research, this book approaches the ongoing research from fundamental, applied and manufacturing perspectives to provide a balanced view of the progress made and the requirements which still have to be met.

Assessing the scientific and technological aspects of lead-free soldering, Lead-Free Soldering in Electronics considers the necessary background and requirements for proper alloy selection. It highlights the metallurgical and mechanical properties; plating and processing technologies; and evaluation methods vital to the production of lead-free solders in electronics. A valuable resource for those interested in promoting environmentally-conscious electronic packaging practices! Responding to increasing environmental and health concerns over lead toxicity, Lead-Free Soldering in Electronics discusses: Soldering inspection and design Mechanical evaluation in electronics Lead-free solder paste and reflow soldering Wave soldering Plating lead-free soldering in electronics Lead-Free Soldering in Electronics will benefit manufacturing, electronics, and mechanical engineers, as well as undergraduate and graduate students in these disciplines.

This unique book provides an up-to-date overview of the concepts behind lead-free soldering techniques. Readers will find a description of the physical and mechanical properties of lead-free solders, in addition to lead-free electronics and solder alloys. Additional topics covered include the reliability of lead-free soldering, tin whiskering and electromigration, in addition to emerging technologies and research.

Discusses the growth mechanisms of tin whiskers and the effective mitigation strategies necessary to reduce whisker growth risks This book covers key tin whisker topics, ranging from fundamental science to practical mitigation strategies. The text begins with a review of the characteristic properties of local microstructures around whisker and hillock grains to identify why these particular grains and locations become predisposed to forming whiskers and hillocks. The book discusses the basic properties of tin-based alloy finishes and the effects of various alloying elements on whisker formation, with a focus on potential mechanisms for whisker suppression or enhancement for each element. Tin whisker risk mitigation strategies for each tier of the supply chain for high reliability electronic systems are also described. Discusses whisker formation factors including surface grain geometry, crystallographic orientation-dependent surface grain boundary structure, and the localization of elastic strain/strain energy density distribution Examines how whiskers and hillocks evolve in time through real-time studies of whisker growth with the scanning electron microscope/focused ion beaming milling (SEM/FIB) Covers characterization methods of tin and tin-based alloy finishes such as transmission electron microscopy (TEM), scanning electron microscopy (SEM), and electron backscatter diffraction (EBSD) Reviews theories of mechanically-induced tin whiskers with case studies using pure tin and other lead-free finishes shown to evaluate the pressure-induced tin whiskers Mitigating Tin Whisker Risks: Theory and Practice is intended for the broader electronic packaging and manufacturing community including: manufacturing engineers, packaging development engineers, as well as engineers and researchers in high reliability industries.