Microstructural stability of Sn-Bi/copper and Sn-Bi-Zn/copper soldered joints under high temperatures.

• Grant number: 24/06998-8
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: June 01, 2024
• End date: May 31, 2026
• Field of knowledge: Engineering - Materials and Metallurgical Engineering - Physical Metallurgy
• Principal Investigator: José Eduardo Spinelli
• Grantee: Carolina de Siqueira Simioli
• Host Institution: Centro de Ciências Exatas e de Tecnologia (CCET). Universidade Federal de São Carlos (UFSCAR). São Carlos , SP, Brazil

Abstract

The increase in the density of integrated circuit components resulting from the continuous miniaturization of electronic devices that populate modern life presents a series of Engineering challenges. Among these challenges, the optimization of alloys intended for soldering of integrated circuit components remains very important. In this context, some alloys from the Sn-Bi system exhibit a set of mechanical properties and adhesion characteristics to Cu substrates that make them excellent alternatives among Pb-free alloys. Sn-Bi alloys have suitable wettability and heat transfer capability. However, mechanical performance and interface layer stability still need improvement. Zn is one of the candidates. Another aspect to be considered in these applications is the effect resulting from the contact of these alloys with the Cu substrate of electronic circuits over time at temperatures higher than ambient. It is known that Sn alloys in contact with Cu under favorable time and temperature conditions give rise to the Cu6Sn5 phase layer formed at the interface region. Depending on Cu6Sn5 morphological features and volume can lead to region embrittlement and consequently compromise the reliability of the solder joint. Thus, the present study aims to contribute through the analysis of the influence of Zn (at two different levels: 2 and 10 wt.%) on the mechanical properties, adhesion to Cu substrate, and morphology and volume of resulting phases in the Sn-40 wt.% Bi alloy.

Scientific publications

(References retrieved automatically from Web of Science and SciELO through information on FAPESP grants and their corresponding numbers as mentioned in the publications by the authors)

SIMIOLI, CAROLINA DE SIQUEIRA; DE GOUVEIA, GUILHERME LISBOA; SPINELLI, JOSE EDUARDO. Assessing the Microstructure of Sn-Bi-Zn Alloys during Semisolid Treatment. ADVANCED ENGINEERING MATERIALS, v. 27, n. 13, p. 9-pg., 2025-04-27. (23/06107-3, 24/06998-8, 24/03615-0)