Effects of salt spray test on lead-free solder alloy

authored by

A. Guédon-Gracia, H. Frémont, B. Plano, J. Y. Delétage, K. Weide-Zaage

Abstract

This paper starts with a bibliographic survey about solder corrosion and experimental results of the corrosion on lead-free solder balls during salt spray tests. Focus is made on the SnAgCu solder alloy. Ball Grid Array assemblies and “Package on Package” components were put up to 96 h in a salt spray chamber at 35 °C with 5% sodium chloride (NaCl) aqua according to the ASTM B117-09 standard. The weight is measured during the test. The solder alloys are observed and analysed along the ageing with optical microscope and scanning electron microscope equipped with an energy-dispersive x-ray system. The solder alloy deterioration is visible after 48 h. The microstructure is analysed in order to determine the corroded residues found on the surface solder balls after the salt spray test. Tin oxychloride (Sn(OH)Cl) is found on BGA solder joints after reflow and on PoP solder balls before reflow. The size of the solder balls has an influence on the corrosion state. Finally a method is developed in order to measure the corrosion product growth on the same sample during the salt environment exposure.

Organisation(s)

Institute of Microelectronic Systems

External Organisation(s)

Universite de Bordeaux

Type

Article

Journal

Microelectronics reliability

Volume

64

Pages

242-247

No. of pages

6

ISSN

0026-2714

Publication date

01.09.2016

Publication status

Published

Peer reviewed

Yes

ASJC Scopus subject areas

Electronic, Optical and Magnetic Materials, Atomic and Molecular Physics, and Optics, Safety, Risk, Reliability and Quality, Condensed Matter Physics, Surfaces, Coatings and Films, Electrical and Electronic Engineering

Electronic version(s)

https://doi.org/10.1016/j.microrel.2016.07.034 (Access: Closed)