Effect of Cu in Pb Free Solder Ball on the Microstructure of BGA Joints with Au/Ni Coated Cu Pad

• Uenishi Keisuke

  Department of Manufacturing Science, Graduate school of Engineering, Osaka University

• Saeki Toshio

  Department of Manufacturing Science, Graduate school of Engineering, Osaka University

• Kohara Yasuhiro

  Department of Manufacturing Science, Graduate school of Engineering, Osaka University

• Kobayashi Kojiro F.

  Department of Manufacturing Science, Graduate school of Engineering, Osaka University

• Shoji Ikuo

  Department of Mecahnical System Engineering, Faculty of Engineering, Gunma University

• Nishiura Masataka

  Corporate Quality Administration Department, Matsushita Electronic Component Co. Ltd

• Yamamoto Masaharu

  Electronic Materials Division, Sumitomo Special Metals Co. Ltd.

書誌事項

タイトル別名

• Effect of Cu in Pb Free Solder Ball on the Microstructure of BGA Joints with Au/Ni Coated Cu Pads

抄録

Effect of Cu in the eutectic Sn–37 mass%Pb or Sn–3.5 mass%Ag solder ball has been investigated on the microstructure and the shear strength of BGA joints with Ni/Au electroplated Cu pad after reflow and the subsequent heat exposure at 423 K . For joints using both Cu free Sn–Pb and Sn–Ag solder balls, a metastable (Au, Ni)Sn₃ reaction layer was formed on the interface between the solder and the pad after reflow soldering and the subsequent heat storage at 423 K, while stable η^′-(Au, Cu, Ni)₆Sn₅ reaction layer was formed for the joints using Cu containing solder balls. The growth rate during heat exposure was much slower for η^′ reaction layer than that for (Au, Ni)Sn₃ reaction layer. All the joints after a heat exposure fractured on the lower shear load than as reflowed joints, but the shear strength of the joint using Cu containing ball was less degraded than that using Cu free solder balls, because η^′ reaction layer grows slower and plays a roll as a good barrier layer to suppress the Ni–Sn interaction. Almost the same effect was confirmed for the BGA joints using Cu cored solder balls, since Cu dissolves into the solder during reflow soldering.

収録刊行物

• MATERIALS TRANSACTIONS

  MATERIALS TRANSACTIONS 42 (5), 756-760, 2001

  公益社団法人 日本金属学会

キーワード

• electroplating
• ball grid array
• Lead free solder
• intermetallic compound
• Copper cored ball
• reaction layer
• shear strength

詳細情報

• CRID: 1390001204247684736
• NII論文ID: 10006548773
• NII書誌ID: AA1151294X
• DOI: 10.2320/matertrans.42.756
• COI: 1:CAS:528:DC%2BD3MXlsVyjtrs%3D
• ISSN: 13475320
• ISSN: 13459678
• ISSN: http://id.crossref.org/issn/09161821
• NDL書誌ID: 5790175
• Web Site: https://ndlsearch.ndl.go.jp/books/R000000004-I5790175
• Web Site: https://www.jstage.jst.go.jp/article/matertrans/42/5/42_5_756/_pdf
• 本文言語コード: en
• データソース種別:
  • JaLC
  • NDL
  • Crossref
  • CiNii Articles
• 抄録ライセンスフラグ: 使用不可