Microstructural evaluation of SAC307 solder alloy sintered by microwaves

• Grant number: 14/01630-0
• Support type: Scholarships in Brazil - Scientific Initiation
• Effective date (Start): August 01, 2014
• Effective date (End): March 31, 2015
• Field of knowledge: Engineering - Materials and Metallurgical Engineering - Physical Metallurgy
• Principal Investigator: José Eduardo Spinelli
• Grantee: Caio Pedroso Turssi
• Home Institution: Centro de Ciências Exatas e de Tecnologia (CCET). Universidade Federal de São Carlos (UFSCAR). São Carlos , SP, Brazil

Abstract

The studies on processing of ceramics by microwaves in the last few years show unique characteristics involving the usage of this kind of energy under high temperatures. In the case of metals seems to be possible a reduction of energy consumption and a decrease on time of processing, beyond the imposition of an inverted distribution of temperature profile and a selective heating. The soldering processes of metals for microelectronics parts have experienced significant changes in the last years such as, for instance, the replacement of Sn-Pb by alternative solder alloys. A promising alternative is associated with the adoption of SnAgCu (SAC) alloys, which are proved to be commercially viable for soldering, especially considering low Ag content. Lead (Pb) cannot be used anymore due to its toxicity and possible environmental damages. Microwaves sintering with atomized Sn-based alloys powders can favor porosity reduction, increase mechanical strength and decrease melting point. Such aspects are very positive regarding to soldering processes with SAC alloys. This work aims both i. to develop sintering process of the Sn-3.0Ag-0.7Cu solder alloy by microwaves and ii. to compare conventional heating route with results from microwaves.