Comparison between SAC405 Lead-Free Solders and EN(P)EPIG and EN(B)EPIG Surface Finishes

Abstract:

In electronics industries, most of them had to shifted their solder materials from leaded solders into lead-free solders due to the environmental concerns and follow the legislation of Restriction of use Hazardous Substances (RoHS). Thus, Sn-Ag-Cu solder is one of the choices that can replace the leaded solder and also offer better properties. This study investigates the comparison between Sn-4.0Ag-0.5Cu (SAC405) and EN(P)EPIG and EN(B)EPIG surface finishes. Reliability of solder joint has been assessed by performing solid state isothermal aging at 150oC for 250 up to 2000 hours. After reflow soldering process, (Cu,Ni)₆Sn₅ intermetallic compound (IMC) is dominated at near centre of solder meanwhile (Ni,Cu)₃Sn₄ IMC is dominated at near outside of solder ball_. Moreover, aging time resulted in an increase in thickness and changed the morphology into more spherical, dense and large grain size. Analysis by optical microscope revealed that the IMC thickness of EN(B)EPIG produced thicker IMC compared to EN(P)EPIG surface finish during reflow as well as isothermal aging.

• Periodical: Applied Mechanics and Materials (Volumes 773-774)
• Pages: 232-236
• DOI: https://doi.org/10.4028/www.scientific.net/AMM.773-774.232
• Online since: July 2015
• Authors: Saliza Azlina*, Ali Ourdjini, Mohd Halim Irwan Ibrahim
• Keywords: Intermetallic Compounds, Isothermal Aging, Lead-Free Solder, Soldering, Surface Finish

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