PMID- 36234099
OWN - NLM
STAT- PubMed-not-MEDLINE
LR  - 20221019
IS  - 1996-1944 (Print)
IS  - 1996-1944 (Electronic)
IS  - 1996-1944 (Linking)
VI  - 15
IP  - 19
DP  - 2022 Sep 29
TI  - The Effect of Micro-Alloying and Surface Finishes on the Thermal Cycling 
      Reliability of Doped SAC Solder Alloys.
LID - 10.3390/ma15196759 [doi]
LID - 6759
AB  - The surface finish (SF) becomes a part of the solder joint during assembly and 
      improves the component's reliability. Furthermore, the SF influences the solder 
      joint's reliability by affecting the thickness of the intermetallic compound 
      (IMC) layer at the solder interface and copper pads. In this experiment, five 
      different alloys are used and compared with the SAC305 alloy, two of which, 
      Innolot and SAC-Bi, are bi-based solder alloys. This study includes three common 
      SFs: electroless nickel immersion gold (ENIG), immersion silver (ImAg), and 
      organic solderability preserve (OSP). The performance of three surface finishes 
      is examined in terms of component characteristic life. All of the boards were 
      isothermally aged for twelve months at 125  degrees C. The boards were then exposed to 
      5000 cycles of thermal cycling at temperatures ranging from -40-+125  degrees C. Most of 
      the current research considers only one or two factors affecting the reliability 
      of the electronic package. This study combines the effect of multiple factors, 
      including solder paste content, SF, isothermal aging, and thermal cycling, to 
      ensure that the test conditions represent real-world applications. In addition, 
      the electronics packages are assembled using commercialized alloys. The current 
      study focuses on a high-performance alloy already present in the electronic 
      market. The failure data were analyzed statistically using the Weibull 
      distribution and design of experiments (DOE) analysis of variance (ANOVA) 
      techniques. The findings reveal that the micro and uniformly distributed 
      precipitates in solder microstructures are critical for high-reliability solder 
      joints. Re-crystallization of the thermally cycled solder joints promotes the 
      local formation of numerous new grains in stress-concentrated zones. As the 
      fracture spreads along these grain boundaries and eventually fails, these new 
      grains participate in crack propagation. Aging significantly worsens this 
      situation. Finally, although the ENIG surface finish with its Ni layer 
      outperforms other SFs, this does not imply that ENIG is more reliable in all 
      solder paste/sphere/finish combinations.
FAU - Akkara, Francy John
AU  - Akkara FJ
AD  - Department of Industrial and Systems Engineering, Auburn University, Auburn, AL 
      36849, USA.
FAU - Hamasha, Sa'd
AU  - Hamasha S
AUID- ORCID: 0000-0002-0967-6002
AD  - Department of Industrial and Systems Engineering, Auburn University, Auburn, AL 
      36849, USA.
FAU - Alahmer, Ali
AU  - Alahmer A
AUID- ORCID: 0000-0002-2994-1504
AD  - Department of Industrial and Systems Engineering, Auburn University, Auburn, AL 
      36849, USA.
AD  - Department of Mechanical Engineering, Faculty of Engineering, Tafila Technical 
      University, Tafila 66110, Jordan.
FAU - Evans, John
AU  - Evans J
AD  - Department of Industrial and Systems Engineering, Auburn University, Auburn, AL 
      36849, USA.
FAU - Belhadi, Mohamed El Amine
AU  - Belhadi MEA
AD  - Department of Industrial and Systems Engineering, Auburn University, Auburn, AL 
      36849, USA.
FAU - Wei, Xin
AU  - Wei X
AD  - Department of Industrial and Systems Engineering, Auburn University, Auburn, AL 
      36849, USA.
LA  - eng
PT  - Journal Article
DEP - 20220929
PL  - Switzerland
TA  - Materials (Basel)
JT  - Materials (Basel, Switzerland)
JID - 101555929
PMC - PMC9570697
OTO - NOTNLM
OT  - ENIG
OT  - SAC
OT  - micro-alloy
OT  - microstructure
OT  - reliability
OT  - surface finishes
COIS- The authors declare no conflict of interest.
EDAT- 2022/10/15 06:00
MHDA- 2022/10/15 06:01
PMCR- 2022/09/29
CRDT- 2022/10/14 02:20
PHST- 2022/08/29 00:00 [received]
PHST- 2022/09/21 00:00 [revised]
PHST- 2022/09/23 00:00 [accepted]
PHST- 2022/10/14 02:20 [entrez]
PHST- 2022/10/15 06:00 [pubmed]
PHST- 2022/10/15 06:01 [medline]
PHST- 2022/09/29 00:00 [pmc-release]
AID - ma15196759 [pii]
AID - materials-15-06759 [pii]
AID - 10.3390/ma15196759 [doi]
PST - epublish
SO  - Materials (Basel). 2022 Sep 29;15(19):6759. doi: 10.3390/ma15196759.