Reliability assessment for SnPb solder and Ag‐Pd bond pad metallization

Abstract

Purpose

To predict the reliability life for SnPb solder and Ag‐Pd bond pad metallization. The aim of selected artificial aging using temperature shock test (TST) and high temperature storage test (HTS). These tests are produced in a short time, the same deterioration in solder joint strength that would occur by natural aging in the actual field condition of up to 10 years or 5,000 h service life.

Design/methodology/approach

This paper using Arrhenius model describes the results of TST and HTS. The TST is aimed to verify the resistance of the assembly to cyclic temperature loading. The HTS test is aimed to check the effect of inter‐diffusion between solder and component and substrate finish, on the mechanical strength of the joints. The paper is organized in four sections: introduction, experimental procedure, experimental results and discussion, conclusion and recommendation.

Findings

The accelerated aging procedures used in this study had successfully modified mainly the outer surface and the interface between a solderable coating and the base metal. The tests that rely on higher temperature increase the diffusivity and the reactivity of the species and so modify internal interfaces such as the intermetallic compound layer, as well as the surface oxide layer. This has provided an effective screening test in understanding the reliability field performance.

Research limitations/implications

For future work it is recommended to run HTS at 175C to validate the estimate for the effective activation energy for diffusion. Next, perform scanning electron microscopy & energy dispersive X‐ray (SEM/EDX) analysis to compare results at 150C for SMD components and studs and explain the different behaviour. Finally, continue T‐shock testing to 2000 cycles.

Practical implications

This has provided an effective screening test in understanding the reliability field performance.

Originality/value

This paper provides a cost effective and practical procedure in screening test for SnPb Solder and Ag‐Pd bond pad metallization. It is an effective solution to electronic manufacturing industry.

Citation

Choon Teo, K. and Lin Ting, Y. (2005), "Reliability assessment for SnPb solder and Ag‐Pd bond pad metallization", Microelectronics International, Vol. 22 No. 2, pp. 21-27. https://doi.org/10.1108/13565360510592199