John Lau, Jerry Gleason, Valeska Schroeder, Gregory Henshall, Walter Dauksher and Bob Sullivan
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…
Abstract
Purpose
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).
Design/methodology/approach
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.
Findings
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.
Originality/value
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.
Details
Keywords
John Lau, Dongkai Shangguan, Todd Castello, Rob Horsley, Joe Smetana, Nick Hoo, Walter Dauksher, Dave Love, Irv Menis and Bob Sullivan
Failure analyses of the lead‐free and SnPb solder joints of high‐density packages such as the plastic ball grid array and the ceramic column grid array soldered on SnCu hot‐air…
Abstract
Failure analyses of the lead‐free and SnPb solder joints of high‐density packages such as the plastic ball grid array and the ceramic column grid array soldered on SnCu hot‐air solder levelling electroless nickel‐immersion gold or NiAu, and organic solderability preservative Entek printed circuit boards are presented. Emphasis is placed on determining the failure locations, failure modes, and intermetallic compound composition for these high‐density packages' solder joints after they have been through 7,500 cycles of temperature cycling. The present results will be compared with those obtained from temperature cycling and finite element analysis.
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John Lau, Jerry Gleason, Valeska Schroeder, Gregory Henshall, Walter Dauksher and Bob Sullivan
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…
Abstract
Purpose
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).
Design/methodology/approach
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.
Findings
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.
Originality/value
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.
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John Lau, Walter Dauksher, Joe Smetana, Rob Horsley, Dongkai Shangguan, Todd Castello, Irv Menis, Dave Love and Bob Sullivan
The lead‐free solder joint reliability of several printed circuit board mounted high‐density packages, when subjected to temperature cycling was investigated by finite element…
Abstract
The lead‐free solder joint reliability of several printed circuit board mounted high‐density packages, when subjected to temperature cycling was investigated by finite element modelling. The packages were a 256‐pin plastic ball grid array (PBGA), a 388‐pin PBGA, and a 1657‐pin ceramic column grid array. Emphasis was placed on the determination of the creep responses (e.g. stress, strain, and strain energy density) of the lead‐free solder joints of these packages.
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Joe Smetana, Rob Horsley, John Lau, Ken Snowdon, Dongkai Shangguan, Jerry Gleason, Irv Memis, Dave Love, Walter Dauksher and Bob Sullivan
The High Density Packaging Users Group conducted a substantial study of the solder joint reliability of high‐density packages using lead‐free solder. The design, material, and…
Abstract
The High Density Packaging Users Group conducted a substantial study of the solder joint reliability of high‐density packages using lead‐free solder. The design, material, and assembly process aspects of the project are addressed in this paper. The components studied include many surface mount technology package types, various lead, and printed circuit board finishes and paste‐in‐hole assembly.
Details
Keywords
John Lau, Nick Hoo, Rob Horsley, Joe Smetana, Dongkai Shangguan, Walter Dauksher, Dave Love, Irv Menis and Bob Sullivan
Temperature cycling tests, and statistical analysis of the results, for various high‐density packages on printed‐circuit boards with Sn‐Cu hot‐air solder levelling, electroless…
Abstract
Temperature cycling tests, and statistical analysis of the results, for various high‐density packages on printed‐circuit boards with Sn‐Cu hot‐air solder levelling, electroless nickel‐immersion gold, and organic solder preservative finishes are investigated in this study. Emphasis is placed on the determination of the life distribution and reliability of the lead‐free solder joints of these high‐density package assemblies while they are subjected to temperature cycling conditions. A data acquisition system, the relevant failure criterion, and the data extraction method will be presented and examined. The life test data are best fitted to the Weibull distribution. Also, the sample mean, population mean, sample characteristic life, true characteristic life, sample Weibull slope, and true Weibull slope for some of the high‐density packages are provided and discussed. Furthermore, the relationship between the reliability and the confidence limits for a life distribution is established. Finally, the confidence levels for comparing the quality (mean life) of lead‐free solder joints of high‐density packages are determined.
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Jeffrey C. Suhling, H.S. Gale, R. Wayne Johnson, M. Nokibul Islam, Tushar Shete, Pradeep Lall, Michael J. Bozack, John L. Evans, Ping Seto, Tarun Gupta and James R. Thompson
The solder joint reliability of ceramic chip resistors assembled to laminate substrates has been a long time concern for systems exposed to harsh environments. In this work, the…
Abstract
The solder joint reliability of ceramic chip resistors assembled to laminate substrates has been a long time concern for systems exposed to harsh environments. In this work, the thermal cycling reliability of several 2512 chip resistor lead‐free solder joint configurations has been investigated. In an initial study, a comparison has been made between the solder joint reliabilities obtained with components fabricated with both tin‐lead and pure tin solder terminations. In the main portion of the reliability testing, two temperature ranges (−40‐125°C and −40‐150°C) and five different solder alloys have been examined. The investigated solders include the normal eutectic Sn‐Ag‐Cu (SAC) alloy recommended by earlier studies (95.5Sn‐3.8Ag‐0.7Cu), and three variations of the lead‐free ternary SAC alloy that include small quaternary additions of bismuth and indium to enhance fatigue resistance.