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The purpose of this paper is to discuss the design, materials, and assembly process aspects of a study, conducted by The High Density Packaging Users Group Consortium, into process development and solder joint reliability of high‐density packages on printed circuit boards using a low‐melting temperature lead‐free solder (Sn‐57 wt%Bi‐1 wt%Ag).

The components studied include several SMT package types and various lead configurations. The assembly process addresses the low‐temperature lead‐free assembly process, inspection and analysis of these boards and packages.

It was found that, the assembly process of the SnBiAg lead‐free test boards is very robust and the assembly yield is almost 100 percent.

The paper is of value by presenting a description of the rationale and material set used for an experiment to test SMT assembly and reliability characteristics using the 57Bi‐42Sn‐1Ag alloy, which has a melting point of 139°C.

The High Density Packaging Users Group Consortium has conducted a study of process development and solder‐joint reliability of high‐density packages on printed circuit boards (PCB) using a low‐melting temperature lead‐free solder. The purpose of this paper is to investigate the reliability tests (e.g. temperature cycling and shock and vibration) and failure analysis (FA) of high‐density packages on PCB with the low‐melting temperature lead‐free solder (Sn‐57 wt%Bi‐1 wt%Ag).

The design for reliability, materials, and assembly process aspects of the project have been discussed in “Design, materials, and assembly process of high‐density packages with a low‐temperature lead‐free solder (SnBiAg)” also published in this journal issue. In this study, reliability tests (e.g. temperature cycling and shock and vibration) and FA of high‐density packages on PCB with the low‐melting temperature lead‐free solder (Sn‐57 wt%Bi‐1 wt%Ag) are investigated.

Lead‐free solder‐joint reliability of high‐density packages, such as the PBGA388, PBGA256, PBGA208, PBGA196, PBGA172, PQFP80, and TSSOP56 were determined by temperature cycling, shock, and vibration tests. Temperature cycling test data for over 8,100 cycles between 0 and 100°C in a 44 min. cycle were statistically analyzed. Shock and vibration test data based on the HP Standard Class Bi‐II Products SPEC have also been reported.

Currently there is a lack of experimental and simulation data and field experience in respect of one of the critical issues for industry – that of solder joint reliability in lead‐free soldering. The paper contains some important research results and recommendations.