{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,28]],"date-time":"2026-04-28T09:40:03Z","timestamp":1777369203960,"version":"3.51.4"},"reference-count":20,"publisher":"MDPI AG","issue":"8","license":[{"start":{"date-parts":[[2025,4,16]],"date-time":"2025-04-16T00:00:00Z","timestamp":1744761600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100003052","name":"Ministry of Trade, Industry and Energy","doi-asserted-by":"publisher","award":["P0020676"],"award-info":[{"award-number":["P0020676"]}],"id":[{"id":"10.13039\/501100003052","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Materials"],"abstract":"<jats:p>In this study, an interconnection was formed between a Cu\/SnAg pillar bump and an Ni-less surface-treated Cu pad through laser-assisted bonding (LAB), and its bonding characteristics were evaluated. The LAB process influences the bond quality and mechanical strength based on the laser irradiation time and laser power density. The growth of the intermetallic compound (IMC) in the joint cross-section was observed via FE-SEM analysis. Under optimized LAB conditions, minimal IMC growth and high bonding strength were achieved compared to conventional thermo-compression bonding (TCB) and mass reflow (MR) processes. As the laser irradiation time and laser power density increased, solder splashing was observed at bump temperatures above 300 \u00b0C. This is hypothesized to be due to the rapid temperature rise causing the flux to vaporize explosively, resulting in simultaneous solder splashing. With increasing laser power density, the failure mode transitioned from the solder to the IMC.<\/jats:p>","DOI":"10.3390\/ma18081834","type":"journal-article","created":{"date-parts":[[2025,4,16]],"date-time":"2025-04-16T10:04:56Z","timestamp":1744797896000},"page":"1834","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":1,"title":["Microstructural and Mechanical Characterization of Cu\/SnAg Pillar Bumps with Ni-Less Surface Finish Utilizing Laser-Assisted Bonding (LAB)"],"prefix":"10.3390","volume":"18","author":[{"given":"Sang-Eun","family":"Han","sequence":"first","affiliation":[{"name":"Regional Industry Innovation Department (Growth Engine), Korea Institute of Industrial Technology, Incheon 21999, Republic of Korea"},{"name":"School of Materials Science and Engineering, Sungkyunkwan University, Suwon 16419, Republic of Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Dong-Gyu","family":"Choi","sequence":"additional","affiliation":[{"name":"Regional Industry Innovation Department (Growth Engine), Korea Institute of Industrial Technology, Incheon 21999, Republic of Korea"},{"name":"Department of Advanced Materials Engineering, Kyonggi University, Suwon 25440, Republic of Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Seonghui","family":"Han","sequence":"additional","affiliation":[{"name":"Regional Industry Innovation Department (Growth Engine), Korea Institute of Industrial Technology, Incheon 21999, Republic of Korea"},{"name":"School of Materials Science and Engineering, Andong National University, Andong 36729, Republic of Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0009-0001-8816-1479","authenticated-orcid":false,"given":"Tae-Young","family":"Lee","sequence":"additional","affiliation":[{"name":"School of Materials Science and Engineering, Tech University of Korea, Siheung 15073, Republic of Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Deok-Gon","family":"Han","sequence":"additional","affiliation":[{"name":"MK Chem & Tech Co., Ltd., Ansan 15434, Republic of Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Hoo-Jeong","family":"Lee","sequence":"additional","affiliation":[{"name":"School of Materials Science and Engineering, Sungkyunkwan University, Suwon 16419, Republic of Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7036-6188","authenticated-orcid":false,"given":"Sehoon","family":"Yoo","sequence":"additional","affiliation":[{"name":"Regional Industry Innovation Department (Growth Engine), Korea Institute of Industrial Technology, Incheon 21999, Republic of Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2025,4,16]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"722","DOI":"10.1126\/science.ade2191","article-title":"Moore\u2019s law: The journey ahead","volume":"378","author":"Lundstrom","year":"2022","journal-title":"Science"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"228","DOI":"10.1109\/TCPMT.2022.3144461","article-title":"Recent advances and trends in advanced packaging","volume":"12","author":"Lau","year":"2022","journal-title":"IEEE Trans. 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Materials, 17.","DOI":"10.3390\/ma17143619"}],"container-title":["Materials"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/1996-1944\/18\/8\/1834\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,9]],"date-time":"2025-10-09T17:15:52Z","timestamp":1760030152000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/1996-1944\/18\/8\/1834"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2025,4,16]]},"references-count":20,"journal-issue":{"issue":"8","published-online":{"date-parts":[[2025,4]]}},"alternative-id":["ma18081834"],"URL":"https:\/\/doi.org\/10.3390\/ma18081834","relation":{},"ISSN":["1996-1944"],"issn-type":[{"value":"1996-1944","type":"electronic"}],"subject":[],"published":{"date-parts":[[2025,4,16]]}}}