Impact of Added Gallium and Phosphorus in Bismuth-Tin Solder Alloys on Mechanical Properties and Microstructure of Intermetallic Layer

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F68407700%3A21230%2F22%3A00358682" target="_blank" >RIV/68407700:21230/22:00358682 - isvavai.cz</a>

Výsledek na webu

<a href="https://doi.org/10.1109/ISSE54558.2022.9812758" target="_blank" >https://doi.org/10.1109/ISSE54558.2022.9812758</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1109/ISSE54558.2022.9812758" target="_blank" >10.1109/ISSE54558.2022.9812758</a>

Jazyk výsledku

angličtina

Název v původním jazyce

Impact of Added Gallium and Phosphorus in Bismuth-Tin Solder Alloys on Mechanical Properties and Microstructure of Intermetallic Layer

Popis výsledku v původním jazyce

The goal of this work was to evaluate changes in mechanical properties and microstructure of the lead-free bismuth-tin alloys when adding gallium and phosphorus. These elements were added originally on account of melting temperature decrease (Ga) and improvement of wetting (P). Six different solders were examined: the eutectic one Bi58Sn42 as a reference, then Bi59Sn40Ga1 and Bi57Sn40Ga3. In addition, the investigation was also performed on all the mentioned alloys with an added trace amount of phosphorus. Mechanical properties were measured by the shear test of a solder ball on a copper substrate with Organic Solderability Preservatives (OSP) surface finish. Furthermore, the small balls of solder alloys were reflowed on boards with three different surface finishes: copper-plated, Hot Air Solder Levelling (HASL), and Electroless Nickel Immersion Gold (ENIG). These coupons were left to aging in the climatic chamber for 500 and 1 000 hours at a temperature of 100 °C. The metallographic cross-sections were made, and the microstructure of the intermetallic layer (IML) was analyzed by scanning electron microscopy (SEM) and energy dispersive X-ray (EDX) analysis. The shear test showed a significant decrease in the shear force by adding gallium. It was also found that the addition of phosphorus has only a minor (but still statistically significant) impact on the shear force. The addition of gallium affected the IML thickness and caused a considerable decrease compared to alloys without Ga. The reason was the composition of the IML. IML of Bi-Sn solder joints consisted of Cu-Sn, whereas the gallium-containing alloys formed IML consisted of Cu-Ga.

Název v anglickém jazyce

Impact of Added Gallium and Phosphorus in Bismuth-Tin Solder Alloys on Mechanical Properties and Microstructure of Intermetallic Layer

Popis výsledku anglicky

The goal of this work was to evaluate changes in mechanical properties and microstructure of the lead-free bismuth-tin alloys when adding gallium and phosphorus. These elements were added originally on account of melting temperature decrease (Ga) and improvement of wetting (P). Six different solders were examined: the eutectic one Bi58Sn42 as a reference, then Bi59Sn40Ga1 and Bi57Sn40Ga3. In addition, the investigation was also performed on all the mentioned alloys with an added trace amount of phosphorus. Mechanical properties were measured by the shear test of a solder ball on a copper substrate with Organic Solderability Preservatives (OSP) surface finish. Furthermore, the small balls of solder alloys were reflowed on boards with three different surface finishes: copper-plated, Hot Air Solder Levelling (HASL), and Electroless Nickel Immersion Gold (ENIG). These coupons were left to aging in the climatic chamber for 500 and 1 000 hours at a temperature of 100 °C. The metallographic cross-sections were made, and the microstructure of the intermetallic layer (IML) was analyzed by scanning electron microscopy (SEM) and energy dispersive X-ray (EDX) analysis. The shear test showed a significant decrease in the shear force by adding gallium. It was also found that the addition of phosphorus has only a minor (but still statistically significant) impact on the shear force. The addition of gallium affected the IML thickness and caused a considerable decrease compared to alloys without Ga. The reason was the composition of the IML. IML of Bi-Sn solder joints consisted of Cu-Sn, whereas the gallium-containing alloys formed IML consisted of Cu-Ga.

Druh

D - Stať ve sborníku

CEP obor

—

OECD FORD obor

20201 - Electrical and electronic engineering

Projekt

—

Návaznosti

S - Specificky vyzkum na vysokych skolach

Rok uplatnění

2022

Kód důvěrnosti údajů

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Název statě ve sborníku

2022 45th International Spring Seminar on Electronics Technology (ISSE)

ISBN

978-1-6654-6589-2

ISSN

2161-2528

e-ISSN

2161-2536

Počet stran výsledku

7

Strana od-do

—

Název nakladatele

IEEE Press

Místo vydání

New York

Místo konání akce

Vienna

Datum konání akce

11. 5. 2022

Typ akce podle státní příslušnosti

WRD - Celosvětová akce

Kód UT WoS článku

000853642200009