{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,11]],"date-time":"2026-09-11T18:07:31Z","timestamp":1789150051526,"version":"build-2803163510"},"reference-count":60,"publisher":"MDPI AG","issue":"14","license":[{"start":{"date-parts":[[2024,7,21]],"date-time":"2024-07-21T00:00:00Z","timestamp":1721520000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Juniper Networks","award":["GR104454"],"award-info":[{"award-number":["GR104454"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Materials"],"abstract":"<jats:p>Bi-doped Sn\u2013Ag\u2013Cu (SAC) microelectronic solder is gaining attention for its utility as a material for solder joints that connect substrates to printed circuit boards (PCB) in future advanced packages, as Bi-doped SAC is reported to have a lower melting temperature, higher strength, higher wettability on conducting pads, and lower intermetallic compound (IMC) formation at the solder-pad interface. As solder joints are subjected to aging during their service life, an investigation of aging-induced changes in the microstructure and mechanical properties of the solder alloy is needed before its wider acceptance in advanced packages. This study focuses on the effects of 1 to 3 wt.% Bi doping in an Sn\u20133.0Ag\u20130.5Cu (SAC305) solder alloy on aging-induced changes in hardness and creep resistance for samples prepared by high cooling rates (&gt;5 \u00b0C\/s). The specimens were aged at ambient and elevated temperatures for up to 90 days and subjected to quasistatic nanoindentation to determine hardness and nanoscale dynamic nanoindentation to determine creep behavior. The microstructural evolution was investigated with a scanning electron microscope in tandem with energy-dispersive spectroscopy to correlate with aging-induced property changes. The hardness and creep strength of the samples were found to increase as the Bi content increased. Moreover, the hardness and creep strength of the 0\u20131 wt.% Bi-doped SAC305 was significantly reduced with aging, while that of the 2\u20133 wt.% Bi-doped SAC305 increased with aging. The changes in these properties with aging were correlated to the interplay of multiple hardening and softening mechanisms. In particular, for 2\u20133 wt.% Bi, the enhanced performance was attributed to the potential formation of additional Ag3Sn IMCs with aging due to non-equilibrium solidification and the more uniform distribution of Bi precipitates. The observations that 2\u20133 wt.% Bi enhances the hardness and creep strength of the SAC305 alloy with isothermal aging to mitigate reliability risks is relevant for solder samples prepared using high cooling rates.<\/jats:p>","DOI":"10.3390\/ma17143602","type":"journal-article","created":{"date-parts":[[2024,7,22]],"date-time":"2024-07-22T14:45:53Z","timestamp":1721659553000},"page":"3602","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":11,"title":["Reliability Risk Mitigation in Advanced Packages by Aging-Induced Precipitation of Bi in Water-Quenched Sn\u2013Ag\u2013Cu\u2013Bi Solder"],"prefix":"10.3390","volume":"17","author":[{"ORCID":"https:\/\/orcid.org\/0009-0008-8891-0602","authenticated-orcid":false,"given":"Vishnu","family":"Shukla","sequence":"first","affiliation":[{"name":"Department of Materials Science and Engineering, Advanced Materials Processing and Analysis Center, University of Central Florida, Orlando, FL 32816, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Omar","family":"Ahmed","sequence":"additional","affiliation":[{"name":"Juniper Networks, Sunnyvale, CA 94089, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Peng","family":"Su","sequence":"additional","affiliation":[{"name":"Juniper Networks, Sunnyvale, CA 94089, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Tengfei","family":"Jiang","sequence":"additional","affiliation":[{"name":"Department of Materials Science and Engineering, Advanced Materials Processing and Analysis Center, University of Central Florida, Orlando, FL 32816, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2024,7,21]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"95","DOI":"10.1016\/S0927-796X(00)00010-3","article-title":"Lead-free Solders in Microelectronics","volume":"27","author":"Abtew","year":"2000","journal-title":"Mater. Sci. Eng."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"12","DOI":"10.1007\/s11837-007-0082-8","article-title":"Public health and environmental benefits of adopting lead-free solders","volume":"59","author":"Ogunseitan","year":"2007","journal-title":"J. Miner. Met. Mater. Soc."},{"key":"ref_3","doi-asserted-by":"crossref","unstructured":"Bath, J. (2007). Lead-Free Solder Joint Reliability. Lead Free Soldering, Springer.","DOI":"10.1007\/978-0-387-68422-2"},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"559","DOI":"10.1016\/j.microrel.2011.10.006","article-title":"Development of SnAg-based lead free solders in electronics packaging","volume":"52","author":"Zhang","year":"2012","journal-title":"Microelectron. Reliab."},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"3578","DOI":"10.1016\/j.matpr.2021.01.335","article-title":"Effects of gallium, phosphorus and nickel addition in lead-free solders: A review","volume":"46","author":"Sonawane","year":"2021","journal-title":"Mater. Today Proc."},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"114599","DOI":"10.1016\/j.microrel.2022.114599","article-title":"Effects of Ga alloying on microstructure and comprehensive performances of Sn\u20139Zn\u20132Bi alloys for the microelectronics industry","volume":"135","author":"Peng","year":"2022","journal-title":"Microelectron. Reliab."},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"570","DOI":"10.1109\/TCPMT.2023.3271269","article-title":"A Review of Low-Temperature Solders in Microelectronics Packaging","volume":"13","author":"Jayaram","year":"2023","journal-title":"IEEE Trans. Compon. Packag. Manuf. Technol."},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"77","DOI":"10.1016\/j.microrel.2017.06.016","article-title":"A review of lead-free solders for electronics applications","volume":"75","author":"Cheng","year":"2017","journal-title":"Microelectron. Reliab."},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"2259","DOI":"10.1007\/s10854-021-07437-6","article-title":"Microstructure and properties of Sn-Ag and Sn-Sb lead-free solders in electronics packaging: A review","volume":"33","author":"Wang","year":"2022","journal-title":"J. Mater Sci. Mater. Electron."},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"3440","DOI":"10.1007\/s10854-014-2036-6","article-title":"Thermal properties of Sn-based solder alloys","volume":"25","author":"Morando","year":"2014","journal-title":"J. Mater. Sci. Mater. Electron."},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"4231","DOI":"10.1016\/j.jmrt.2023.06.193","article-title":"Recent advances in Sn-based lead-free solder interconnects for microelectronics packaging: Materials and technologies","volume":"25","author":"Ansari","year":"2023","journal-title":"J. Mater. Res. Technol."},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"1409","DOI":"10.1007\/s11664-011-1534-z","article-title":"Characterizing the Mechanical Properties of Actual SAC105, SAC305, and SAC405 Solder Joints by Digital Image Correlation","volume":"40","author":"Nguyen","year":"2011","journal-title":"J. Electron. Mater."},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"49","DOI":"10.1515\/pmp-2018-0006","article-title":"Investigating the microstructural and mechanical properties of pure lead-free soldering materials (SAC305 & SAC405)","volume":"18","author":"Kumar","year":"2018","journal-title":"Powder Metall. Prog."},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"2247","DOI":"10.1007\/s11665-013-0492-4","article-title":"Effects of PCB Substrate Surface Finish and Flux on Solderability of Lead-Free SAC305 Alloy","volume":"22","author":"Siewiorek","year":"2013","journal-title":"J. Mater. Eng. Perform."},{"key":"ref_15","doi-asserted-by":"crossref","unstructured":"Abueed, M., Athamneh, R., Tanash, M., and Hamasha, S. (2022). The Reliability of SAC305 Individual Solder Joints during Creep\u2013Fatigue Conditions at Room Temperature. Crystals, 12.","DOI":"10.3390\/cryst12091306"},{"key":"ref_16","doi-asserted-by":"crossref","unstructured":"Dusek, K., Vesely, P., Busek, D., Petrac, A., Geczy, A., Illes, B., and Krammer, O. (2021). Influence of Flux and Related Factors on Intermetallic Layer Growth within SAC305 Solder Joints. Materials, 14.","DOI":"10.3390\/ma14247909"},{"key":"ref_17","doi-asserted-by":"crossref","unstructured":"Su, S., Akkara, F., Abueed, M., Jian, M., Hamasha, S., Suhling, J., and Lall, P. (June, January 29). Fatigue Properties of Lead-free Doped Solder Joints. Proceedings of the 2018 17th IEEE Intersociety Conference on Thermal and Thermomechanical Phenomena in Electronic Systems (ITherm), San Diego, CA, USA.","DOI":"10.1109\/ITHERM.2018.8419566"},{"key":"ref_18","doi-asserted-by":"crossref","unstructured":"Fu, N., Wu, J., Ahmed, S., Suhling, J., and Lall, P. (September, January 29). Investigation of Aging Induced Evolution of the Microstructure of SAC305 Lead Free Solder. Proceedings of the ASME 2017 International Technical Conference and Exhibition on Packaging and Integration of Electronic and Photonic Microsystems, San Francisco, California, USA.","DOI":"10.1115\/IPACK2017-74266"},{"key":"ref_19","doi-asserted-by":"crossref","unstructured":"Wu, J., Ahmed, S., Suhling, J., and Lall, P. (2019, January 28\u201331). Investigation of Aging Induced Microstructural Changes in Doped SAC+X Solders. Proceedings of the 2019 18th IEEE Intersociety Conference on Thermal and Thermomechanical Phenomena in Electronic Systems (ITherm), Las Vegas, NV, USA.","DOI":"10.1109\/ITHERM.2019.8756501"},{"key":"ref_20","doi-asserted-by":"crossref","unstructured":"Shukla, V., Ahmed, O., Jalilvand, G., Mehta, A., Su, P., and Jiang, T. (July, January 1). Effects of Aging on Microstructure and Mechanical Properties of Sn-Ag-Cu-Bi Solder Alloys. Proceedings of the 2021 IEEE 71st Electronic Components and Technology Conference (ECTC), San Diego, CA, USA.","DOI":"10.1109\/ECTC32696.2021.00116"},{"key":"ref_21","doi-asserted-by":"crossref","unstructured":"Hasnine, M., Suhling, J., Prorok, B., Bozack, J., and Lall, P. (2014, January 27\u201330). Exploration of aging induced evolution of solder joints using nanoindentation and microdiffraction. Proceedings of the 2014 IEEE 64th Electronic Components and Technology Conference (ECTC), Orlando, FL, USA.","DOI":"10.1109\/ECTC.2014.6897315"},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"1397","DOI":"10.1016\/S1003-6326(21)65585-1","article-title":"Influence of bismuth on microstructure, thermal properties, mechanical performance, and interfacial behavior of SAC305-xBi\/Cu solder joints","volume":"31","author":"Chantaramanee","year":"2021","journal-title":"Trans. Nonferrous Met. Soc. China"},{"key":"ref_23","doi-asserted-by":"crossref","unstructured":"Ahmed, S., Suhling, J., and Lall, P. (June, January 30). The Anand parameters of aging resistant doped solder alloys. Proceedings of the 2017 16th IEEE Intersociety Conference on Thermal and Thermomechanical Phenomena in Electronic Systems (ITherm), Orlando, FL, USA.","DOI":"10.1109\/ITHERM.2017.7992647"},{"key":"ref_24","doi-asserted-by":"crossref","first-page":"611","DOI":"10.1109\/TCPMT.2019.2949719","article-title":"Fatigue Behavior of SAC-Bi and SAC305 Solder Joints With Aging","volume":"10","author":"Athamneh","year":"2020","journal-title":"IEEE Trans.Compon. Packag. Manuf. Technol."},{"key":"ref_25","doi-asserted-by":"crossref","first-page":"115020","DOI":"10.1016\/j.microrel.2023.115020","article-title":"Effect of Bi content and aging on solder joint shear properties considering strain rate","volume":"146","author":"Belhadi","year":"2023","journal-title":"Microelectron. Reliab."},{"key":"ref_26","unstructured":"Belhadi, M., Akkara, F., Athamenh, R., Abueed, M., Hamasha, S., Ali, H., Suhling, J., and Lall, P. (2020, January 21\u201323). The Effect of Bi on the Mechanical Properties of Aged SAC Solder Joint. Proceedings of the 2020 19th IEEE Intersociety Conference on Thermal and Thermomechanical Phenomena in Electronic Systems (ITherm), Orlando, FL, USA."},{"key":"ref_27","doi-asserted-by":"crossref","unstructured":"Shukla, V., Ayers, N., Moreno, A., Crutchfield, N., Lyons, D., Ahmed, O., Su, P., Glasauer, B., and Jiang, T. (June, January 31). The Effects of Bi Doping and Aging on Viscoplasticity of Sn-Ag-Cu-Bi alloys. Proceedings of the 2022 IEEE 72nd Electronic Components and Technology Conference (ECTC), San Diego, CA, USA.","DOI":"10.1109\/ECTC51906.2022.00266"},{"key":"ref_28","doi-asserted-by":"crossref","unstructured":"Yang, T., Chen, Y., You, K., Dong, Z., Jia, Y., Wang, G., Peng, J., Cai, S., Luo, X., and Liu, C. (2022). Effect of Bi, Sb, and Ti on Microstructure and Mechanical Properties of SAC105 Alloys. Materials, 15.","DOI":"10.3390\/ma15144727"},{"key":"ref_29","doi-asserted-by":"crossref","first-page":"382","DOI":"10.1016\/j.jallcom.2008.05.082","article-title":"Kinetics of intermetallic compound layers and shear strength in Bi-bearing SnAgCu\/Cu soldering couples","volume":"473","author":"Zhao","year":"2009","journal-title":"J. Alloys Compd."},{"key":"ref_30","doi-asserted-by":"crossref","first-page":"s739","DOI":"10.1016\/S1003-6326(06)60292-6","article-title":"Effects of bismuth on growth of intermetallic compounds in Sn-Ag-Cu Pb-free solder joints","volume":"16","author":"Li","year":"2006","journal-title":"Trans. Nonferrous Met. Soc. China"},{"key":"ref_31","doi-asserted-by":"crossref","first-page":"101787","DOI":"10.1016\/j.mtcomm.2020.101787","article-title":"Effects of bismuth and nickel on the microstructure evolution of Sn-Ag-Cu (SAC)-based solders","volume":"26","author":"Sivakumar","year":"2021","journal-title":"Mater. Today Commun."},{"key":"ref_32","doi-asserted-by":"crossref","first-page":"367","DOI":"10.1016\/j.msea.2018.08.071","article-title":"Physical and mechanical properties of synthesized low Ag\/lead-free Sn-Ag-Cu-xBi (x = 0, 1, 2.5, 5 wt%) solders","volume":"735","author":"Sayyadi","year":"2018","journal-title":"Mater. Sci.Eng. A"},{"key":"ref_33","doi-asserted-by":"crossref","first-page":"108281","DOI":"10.1016\/j.matdes.2019.108281","article-title":"The effect of Bi on the microstructure, electrical, wettability and mechanical properties of Sn-0.7Cu-0.05Ni alloys for high strength soldering","volume":"186","author":"Ramli","year":"2020","journal-title":"Mater. Des."},{"key":"ref_34","doi-asserted-by":"crossref","first-page":"40","DOI":"10.4028\/www.scientific.net\/SSP.273.40","article-title":"Influence of Bismuth in Sn-Based Lead-Free Solder\u2014A Short Review","volume":"273","author":"Razak","year":"2018","journal-title":"Solid State Phenom."},{"key":"ref_35","doi-asserted-by":"crossref","first-page":"268","DOI":"10.1016\/j.jallcom.2014.12.034","article-title":"Development of new multicomponent Sn\u2013Ag\u2013Cu\u2013Bi lead-free solders for low-cost commercial electronic assembly","volume":"627","author":"Gouda","year":"2015","journal-title":"J. Alloys Compd."},{"key":"ref_36","doi-asserted-by":"crossref","unstructured":"Ahmed, S., Basit, M., Suhling, J.C., and Lall, P. (June, January 31). Effects of aging on SAC-Bi solder materials. Proceedings of the 2016 15th IEEE Intersociety Conference on Thermal and Thermomechanical Phenomena in Electronic Systems (ITherm), Las Vegas, NV, USA.","DOI":"10.1109\/ITHERM.2016.7517621"},{"key":"ref_37","doi-asserted-by":"crossref","first-page":"378","DOI":"10.1007\/s10854-018-0302-8","article-title":"Precipitation and coarsening of bismuth plates in Sn\u2013Ag\u2013Cu\u2013Bi and Sn\u2013Cu\u2013Ni\u2013Bi solder joints","volume":"30","author":"Belyakov","year":"2019","journal-title":"J. Mater. Sci. Mater. Electron."},{"key":"ref_38","doi-asserted-by":"crossref","first-page":"116","DOI":"10.1007\/s11664-019-07666-w","article-title":"Thermal Preconditioning and Restoration of Bismuth-Containing, Lead-Free Solder Alloys","volume":"49","author":"Delhaise","year":"2020","journal-title":"J. Electron. Mater."},{"key":"ref_39","doi-asserted-by":"crossref","unstructured":"Hamasha, M.M., Hamasha, K., and Hamasha, S. (2023). Impact of Isothermal Aging on Mechanical Properties of 92.8%Sn-3%Ag-0.5%Cu-3.3%Bi (Cyclomax) Solder Joints. Metals, 13.","DOI":"10.3390\/met13030591"},{"key":"ref_40","doi-asserted-by":"crossref","first-page":"182","DOI":"10.1007\/s11664-015-4189-3","article-title":"Effects of Cooling Rate on the Microstructure and Morphology of Sn-3.0Ag-0.5Cu Solder","volume":"45","author":"Lee","year":"2016","journal-title":"J. Electron. Mater."},{"key":"ref_41","doi-asserted-by":"crossref","first-page":"112707","DOI":"10.1016\/j.matchar.2023.112707","article-title":"Hypo-eutectic microstructure formation and nanomechanical response in Sn-3.0Ag-0.5Cu solder balls: Effects of undercooling","volume":"198","author":"Wang","year":"2023","journal-title":"Mater. Charact."},{"key":"ref_42","doi-asserted-by":"crossref","first-page":"111530","DOI":"10.1016\/j.matchar.2021.111530","article-title":"Effects of size and cooling rate on solidification behavior of freestanding Sn-3.0Ag-0.5Cu solder balls","volume":"182","author":"Ren","year":"2021","journal-title":"Mater. Charact."},{"key":"ref_43","doi-asserted-by":"crossref","unstructured":"Mueller, M., Wiese, S., Roellig, M., and Wolter, K. (June, January 29). Effect of Composition and Cooling Rate on the Microstructure of SnAgCu-Solder Joints. Proceedings of the 2007 Proceedings 57th Electronic Components and Technology Conference, Sparks, NV, USA.","DOI":"10.1109\/ECTC.2007.374006"},{"key":"ref_44","doi-asserted-by":"crossref","unstructured":"Wei, G., and Wang, L. (2012, January 13\u201316). Effects of cooling rate on microstructure and microhardness of lead-free Sn-3. 0Ag-0.5Cu solder. In Proceedings of the 2012 13th International Conference on Electronic Packaging Technology & High Density Packaging, Guilin, China.","DOI":"10.1109\/ICEPT-HDP.2012.6474657"},{"key":"ref_45","unstructured":"JEDEC Solid State Association (2024, May 12). Moisture\/Reflow Sensitivity Classification for Non-Hermitic Surface Mount Devices (SMDS) 2022, J-STD-020F. Available online: https:\/\/www.jedec.org\/standards-documents\/docs\/j-std-020e."},{"key":"ref_46","unstructured":"Alam, M. (2019). Mechanical Behavior and Microstructural Evolution of Lead Free Solder Alloys in Harsh Environmental Applications. [Doctoral Dissertation, Auburn University]."},{"key":"ref_47","doi-asserted-by":"crossref","unstructured":"Dudash, V., Machani, K.V., Meier, K., Geisler, H., Mueller, M., Kuechenmeister, F., Wieland, M., and Bock, K. (2023, January 5\u20138). Temperature-dependent Creep Characterization of Lead-free Solder Alloys Using Nanoindentation for Finite Element Modeling. Proceedings of the 2023 IEEE 25th Electronics Packaging Technology Conference (EPTC), Singapore.","DOI":"10.1109\/EPTC59621.2023.10457727"},{"key":"ref_48","doi-asserted-by":"crossref","first-page":"140203","DOI":"10.1016\/j.msea.2020.140203","article-title":"Nanoindentation creep properties of lead-free nanocomposite solders reinforced by modified carbon nanotubes","volume":"797","author":"Khodabakhshi","year":"2020","journal-title":"Mater. Sci.Eng. A"},{"key":"ref_49","doi-asserted-by":"crossref","unstructured":"Alam, M.S., Hassan, K.R., Fahim, A., Wu, J., Ahmed, S., Suhling, J.C., and Lall, P. (2020, January 3\u201330). Investigation of the Mechanical Behavior of SAC305 Solder Joints at Extreme High Temperatures Using Nanoindentation. Proceedings of the 2020 IEEE 70th Electronic Components and Technology Conference (ECTC), Orlando, FL, USA.","DOI":"10.1109\/ECTC32862.2020.00338"},{"key":"ref_50","doi-asserted-by":"crossref","unstructured":"Wang, S., Yao, Y., and Long, X. (2019). Critical Review of Size Effects on Microstructure and Mechanical Properties of Solder Joints for Electronic Packaging. Appl. Sci., 9.","DOI":"10.3390\/app9020227"},{"key":"ref_51","unstructured":"Syed, A. (2004, January 4). Accumulated creep strain and energy density based thermal fatigue life prediction models for SnAgCu solder joints. Proceedings of the 2004 54th Electronic Components and Technology Conference, Las Vegas, NV, USA."},{"key":"ref_52","doi-asserted-by":"crossref","unstructured":"Shukla, V., Ahmed, O., Su, P., Tian, T., and Jiang, T. (2024). Effect of Bi on the Tensile and Viscoplastic Behavior of Sn-Ag-Cu-Bi Alloys Used for Microelectronics Applications. Metals, 14.","DOI":"10.3390\/met14070803"},{"key":"ref_53","unstructured":"Seelig, K., Pigeon, K., O\u2019Brien, S., and Tafoya, C. (2008). The Quick Pocket Reference for Tin\/Lead and Lead-Free Solder Assembly, AIM Solder."},{"key":"ref_54","doi-asserted-by":"crossref","first-page":"100234","DOI":"10.1016\/j.mtla.2019.100234","article-title":"Effects of Ni nanoparticles addition on the microstructure, electrical and mechanical properties of Sn-Ag-Cu alloy","volume":"5","author":"Gain","year":"2019","journal-title":"Materialia"},{"key":"ref_55","doi-asserted-by":"crossref","first-page":"114041","DOI":"10.1016\/j.microrel.2021.114041","article-title":"Effects of bismuth additions on mechanical property and microstructure of SAC-Bi solder joint under current stressing","volume":"117","author":"Hu","year":"2021","journal-title":"Microelectron. Reliab."},{"key":"ref_56","doi-asserted-by":"crossref","unstructured":"Wu, J., Suhling, J., and Lall, P. (2019, January 28\u201331). Microstructural Evolution in SAC+X Solders Subjected to Aging. Proceedings of the 2019 IEEE 69th Electronic Components and Technology Conference (ECTC), Las Vegas, NV, USA.","DOI":"10.1109\/ECTC.2019.00170"},{"key":"ref_57","doi-asserted-by":"crossref","unstructured":"Wu, J., Fu, N., Ahmed, S., Suhling, J., and Lall, P. (June, January 29). Investigation of Microstructural Evolution in SAC Solders Exposed to Short-Term and Long-Term Aging. Proceedings of the 2018 17th IEEE Intersociety Conference on Thermal and Thermomechanical Phenomena in Electronic Systems (ITherm), San Diego, CA, USA.","DOI":"10.1109\/ITHERM.2018.8419474"},{"key":"ref_58","doi-asserted-by":"crossref","unstructured":"Li, Y., Long, W., Hu, X., and Fu, Y. (2018). Interfacial Reaction and IMC Growth of an Ultrasonically Soldered Cu\/SAC305\/Cu Structure during Isothermal Aging. Materials, 11.","DOI":"10.3390\/ma11010084"},{"key":"ref_59","doi-asserted-by":"crossref","unstructured":"Liu, Y., Sun, F., Wang, G., and Zou, P. (2012, January 18\u201321). Nanoindentation properties of as-soldered low-Ag SAC-Bi-Ni\/Cu. Proceedings of the 2012 7th International Forum on Strategic Technology (IFOST), Tomsk, Russia.","DOI":"10.1109\/IFOST.2012.6357535"},{"key":"ref_60","doi-asserted-by":"crossref","first-page":"056504","DOI":"10.1088\/2053-1591\/ab8b1d","article-title":"Study on aging strengthening and nano precipitates of Cu-Ni-Mn-Fe alloy","volume":"7","author":"Zou","year":"2020","journal-title":"Mater. Res. Express"}],"container-title":["Materials"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/1996-1944\/17\/14\/3602\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,10]],"date-time":"2025-10-10T15:20:43Z","timestamp":1760109643000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/1996-1944\/17\/14\/3602"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2024,7,21]]},"references-count":60,"journal-issue":{"issue":"14","published-online":{"date-parts":[[2024,7]]}},"alternative-id":["ma17143602"],"URL":"https:\/\/doi.org\/10.3390\/ma17143602","relation":{},"ISSN":["1996-1944"],"issn-type":[{"value":"1996-1944","type":"electronic"}],"subject":[],"published":{"date-parts":[[2024,7,21]]}}}