Thermal and mechanical reliability of low-temperature solder alloys for handheld devices

Ribas, Morgana; Chegudi, Sujatha; Kumar, Anil; Pandher, Ranjit; Raut, Rahul; Mukherjee, Sutapa; Sarkar, Siuli; Singh, B. P.

doi:10.1109/eptc.2014.7028385

Cited by 2 publications

(3 citation statements)

References 13 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…[24][25] These properties of Bi lead to an understanding of poor drop performance compared to Sn-Ag3.0-Cu0.5 that has a drop shock performance 4x of the SnBi alloy. [26] Despite the decline in Sn-Bi the results of many micro alloying studies show the addition of Ag by 0.25wt% to 1.0wt% to SnBi improved the ductility and reduced brittleness an increase in tensile strength and elongation and young's modulus, a good indicator of drop shock performance of a SnBi solder joint. [27][28] A study {27} confi rmed these improved mechanical and thermal properties of SnBi with small Ag additions and the preferred alloy being commercialized is Sn42/Bi57.6/Ag0.4.…”

Section: Literature Review Prior Low Temperature Solder Studiesmentioning

confidence: 99%

“…An indication of a potentially similar challenge for mixed SAC-SnBi alloy assemblies exists in literature. [15,26,33] Research must address manufacturing process infl uences on mixing with the concern of proper solder joint collapse related to correct volumes of pastes and optimal profi les of various size components or risk further reduction of mechanical properties compared to SAC alloy solder joints. [12,23,34] Optimal refl ow profi les are a key factor for mixing and solder joint collapse height as a function of peak temperature.…”

Section: Literature Review Prior Low Temperature Solder Studiesmentioning

confidence: 99%

See 1 more Smart Citation

Properties of Mixing SAC Solder Alloys with Bismuth-Containing Solder Alloys for a Low Reflow Temperature Process

Swanson,

Anselm

2023

Journal of SMT

View full text Add to dashboard Cite

The subject of extensive research has been the establishing of lower temperature soldering of electronic assemblies that are similar to the once common yet still preferred eutectic Tin-Lead (SnPb) soldering processes that are below 217˚C. This research measured and compared the mixing mechanisms of paste and ball dissolution. Mixed soldered assemblies will have different dissolution results that are dependent on the peak reflow temperature. The hypothesis for this experiment was to determine the relationship of various times above the melting point of low temperature solders containing Bismuth. The results measured are from solder joints of both SAC305 and Bismuth containing solders formed at lower process temperatures compared to the standard high temperatures which peak at 230˚C-260˚C. The Bismuth containing solders evaluated start with the highest to lowest weight percentage of Bismuth, the eutectic 58Bismuth/42Tin (58Bi/42Sn), 57Bi/42Sn/1Ag and a propriety alloy that has a lower Bismuth content along with various micro alloys, defined as 40-58Bi/Sn/X (X representing proprietary micro alloys or doping). The assembly was with an 18mil 96.5Tin/3.0Silver/0.5Copper (SAC305) solder ball mixed with each solder paste. These solder alloys were exposed to three different peak temperatures 180˚C, 195˚C, 205˚C. Another reflow profile attribute of focus was times above 138˚C - the melting point of the eutectic Sn58Bi alloy, this term used throughout the study is referred to Time Above Melting (TAM). The ball and paste assembly used the times above melting of 120sec and 240sec to represent process extremes and verify their significance on improving mixing level results. The average mixing % levels were recorded and compared for each solder joint combination to test the theory that the solder paste solidifies during the time above melting (TAM) within the reflow oven. [1] This experiment effectively demonstrates that the reflow profile parameter for time above melting has limited effectiveness in additionally mixing the paste with the BGA solder ball. Optimization of mixing percentages will need to be achieved by optimizing the paste and ball volumes.

show abstract

Section: Literature Review Prior Low Temperature Solder Studiesmentioning

confidence: 99%

Section: Literature Review Prior Low Temperature Solder Studiesmentioning

confidence: 99%

Properties of Mixing SAC Solder Alloys with Bismuth-Containing Solder Alloys for a Low Reflow Temperature Process

Swanson,

Anselm

2023

Journal of SMT

View full text Add to dashboard Cite

show abstract

“…Common low temperature solders consist of tin (Sn) with varying compositions of bismuth (Bi) or indium (In). Bi soldering alloys tend to have higher strength but reduced ductility and susceptibility to thermal aging [52][53][54][55][56][57][58]. On the other hand, In is a much softer alloy, which reduces its strength, yet it has greater ductility.…”

Section: Introductionmentioning

confidence: 99%

Interconnections for Additively Manufactured Hybridized Printed Electronics in Harsh Environments

Neff

Elston

Schrand

2020

Designs

View full text Add to dashboard Cite

The ability to fabricate functional 3D conductive elements via additive manufacturing has opened up a unique sector of ‘hybridized printed electronics’. In doing so, many of the rigid standards (i.e., planar circuit boards, potting, etc.,) of traditional electronics are abandoned. However, one critical challenge lies in producing robust and reliable interconnections between conductive inks and traditional hardware, especially when subjected to harsh environments. This research examines select material pairings for the most resilient interconnection. The method of test is wire bond pull testing that would represent a continuous strain on a connection and high acceleration testing of up to 50,000 g that would represent a sudden shock that electronics may experience in a drop or crash. Although these two environments may be similar to an overall energy exerted on the connection, the rate of force exerted may lead to different solutions. The results of this research provide insight into material selection for printed electronic interconnections and a framework for interconnection resiliency assessment, which is a critical aspect in realizing the production of next generation electronics technologies for the most demanding environments.

show abstract

Thermal and mechanical reliability of low-temperature solder alloys for handheld devices

Cited by 2 publications

References 13 publications

Properties of Mixing SAC Solder Alloys with Bismuth-Containing Solder Alloys for a Low Reflow Temperature Process

Properties of Mixing SAC Solder Alloys with Bismuth-Containing Solder Alloys for a Low Reflow Temperature Process

Interconnections for Additively Manufactured Hybridized Printed Electronics in Harsh Environments

Contact Info

Product

Resources

About